Ecological Monitoring and Compliance Program 2012 Report – National Security Technologies LLC (TPD1207031)

EXECUTIVE SUMMARY

The Ecological Monitoring and Compliance Program (EMAC), funded through the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO, formerly Nevada Site Office), monitors the ecosystem of the Nevada National Security Site (NNSS) and ensures compliance with laws and regulations pertaining to NNSS biota. This report summarizes the program’s activities conducted by National Security Technologies, LLC (NSTec), during calendar year 2012.

Program activities included (a) biological surveys at proposed construction sites, (b) desert tortoise compliance, (c) ecosystem monitoring, (d) sensitive plant species monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat restoration monitoring, and (g) monitoring of the Nonproliferation Test and Evaluation Complex (NPTEC). During 2012, all applicable laws, regulations, and permit requirements were met, enabling EMAC to achieve its intended goals and objectives.

Sensitive and protected/regulated species of the NNSS include 42 plants, 1 mollusk, 2 reptiles, 236 birds, and 27 mammals. These species are protected, regulated, or considered sensitive according to state or federal regulations and natural resource agencies and organizations. The desert tortoise (Gopherus agassizii) is the only species on the NNSS protected under the Endangered Species Act. Biological surveys for the presence of sensitive and protected/regulated species and important biological resources on which they depend were conducted for 20 projects. A total of 145.17 hectares (ha) was surveyed for these projects. Sensitive and protected/regulated species and important biological resources found during these surveys included Joshua trees (Yucca brevifolia) and cacti. NSTec provided to project managers a written summary report of all survey findings and mitigation recommendations, where applicable. All flagged desert tortoise burrows were avoided during project activities.

Of the 18 projects on the NNSS, 13 occurred within the range of the threatened desert tortoise. No desert tortoises were accidentally killed or captured during project activities. One desert tortoise was injured by a vehicle along Jackass Flats road in Area 25. The tortoise walked away from the site, so the injury did not appear to be life-threatening. Seven tortoises were removed from roads to avoid being killed or injured. Approximately 6.17 ha of desert tortoise habitat were disturbed. Eleven desert tortoises were captured, radio-transmittered, and tracked as part of a study to understand how they interact with roads and to learn more about their fine-scale habitat use.

From 1978 until 2012, there has been an average of 11.7 wildland fires per year on the NNSS with an average of about 84.6 ha burned per fire. There were 11 wildland fires documented on the NNSS during 2012. Seven fires were caused by lightning, burning a total of 206.0 ha; two fires were caused by ordnance, for a total of 6.5 ha; one fire was caused by high winds, burning 4 ha; and one was caused by a vehicle, which burned about 0.4 ha. Total area burned was approximately 217 ha.

West Nile virus surveillance continued in 2012, but because of moldy samples, no mosquitoes were tested. Selected natural water sources were monitored to assess trends in physical and biological parameters. Several plastic-lined sumps were visited, and no dead animals were found in the sumps. In order to minimize the impact to wildlife from drying up four well ponds as a water conservation measure, five water troughs were installed. Motion-activated cameras were set up at each trough to document wildlife use.

A new site-specific ranking system for sensitive plants on the NNSS was developed. Field surveys in 2012 focused on rock purpusia (Ivesia arizonica var. saxosa) and white bearpoppy (Arctomecon merriamii). New populations of both species were documented. Kingston Mountains bedstraw (Galium hilendiae ssp. kingstonense) was verified as the subspecies that occurs on the NNSS, and two new populations were documented during other monitoring activities. Several new locations of Pahute green gentian (Frasera pahutensis) were also documented during other monitoring activities. No long-term monitoring plots were sampled this year.

Surveys of sensitive and protected/regulated animals during 2012 focused on bats, wild horses (Equus caballus), mule deer (Odocoileus hemionus), and mountain lions (Puma concolor). The wild horse population is stable at about 35 individuals, with very few foals surviving through the year. Mule deer abundance and density measured with standardized deer surveys showed a 50% decline. A total of 124 mountain lion images (i.e., photographs or video clips) were taken during 163,487 camera hours at 22 of 33 sites sampled. Information about other noteworthy wildlife observations, bird mortalities, Migratory Bird Treaty Act compliance, and a summary of nuisance animals and their control on the NNSS are also presented.

A mountain lion telemetry study continued in 2012 with the capture of three males and a female in May and June. All four (NNSS4, NNSS5, NNSS6, and NNSS7) were tracked using global positioning system satellite transmitters to determine food habits, home range, and habitat use during 2012. Combining data from all four mountain lions, a total of 54 prey items were found, including 42 mule deer, 5 wild horse foals, 3 desert bighorn sheep (Ovis canadensis nelsoni), 2 carnivores, 1 pronghorn antelope (Antilocapra americana), and 1 unknown ungulate. NNSS6, the female, was found dead during early August. Cause of death is unknown but may be disease-related.

Two previously revegetated sites on the NNSS and two on the Tonopah Test Range (TTR) were monitored in 2012. The cover cap on the U-3ax/bl disposal unit, revegetated in 2000, and the Control Point (CP) waterline, revegetated in 2009, were the restoration sites monitored on the NNSS. The Corrective Action Unit (CAU) 400-Five Points Landfill site, revegetated in 1997, and the CAU 407 Rollercoaster RADSAFE site, revegetated in 2000, were the restoration sites monitored on the TTR. Plant cover and density were recorded at the sites and where applicable reclamation success standards were evaluated. The 92-Acre Site at the Radioactive Waste Management Complex was revegetated to establish an evapotranspirative cover over buried waste. Revegetation included site preparation, seeding, mulching, crimping, and irrigating four areas, totaling 18 hectares (ha).

One chemical spill test plan was reviewed in 2012, but no baseline monitoring was needed or conducted at NPTEC.

Ecological Monitoring and Compliance Program 2012 Report

TABLE OF CONTENTS

ACRONYMS AND ABBREVIATIONS……………………………………………………………………………… xiii

1.0       INTRODUCTION………………………………………………………………………………………………….. 1

2.0               BIOLOGICAL SURVEYS……………………………………………………………………………………….. 3

2.1         Sites Surveyed and Sensitive and Protected/Regulated Species Observed……………………………. 3

2.2         Potential Habitat Disturbance……………………………………………………………………………………. 3

3.0               DESERT TORTOISE COMPLIANCE………………………………………………………………………. 13

3.1         Project Surveys and Compliance Documentation…………………………………………………………. 13

3.2         Mitigation for Loss of Tortoise Habitat………………………………………………………………………. 17

3.3         Conservation Recommendation Studies……………………………………………………………………… 17

3.3.1             Road Study…………………………………………………………………………………………………… 17

3.3.2             Traffic Counters…………………………………………………………………………………………….. 21

3.4         Coordination with Other Biologists and Wildlife Agencies…………………………………………….. 21

4.0               ECOSYSTEM MONITORING………………………………………………………………………………… 23

4.1         Vegetation Survey for Wildland Fire Hazard Assessment………………………………………………. 23

4.1.1             Survey Methods…………………………………………………………………………………………….. 24

4.1.2             Survey Results………………………………………………………………………………………………. 28

4.2         West Nile Virus Surveillance…………………………………………………………………………………… 36

4.3         Habitat Monitoring: Additional Reptile Sampling………………………………………………………… 37

4.4         Natural Water Source Monitoring…………………………………………………………………………….. 38

4.4.1             Existing Water Sources…………………………………………………………………………………… 38

4.4.2             New Water Sources………………………………………………………………………………………… 41

4.5         Constructed Water Source Monitoring……………………………………………………………………….. 43

4.5.1             Plastic Sump Monitoring…………………………………………………………………………………. 43

4.5.2            Mitigating Water Loss for Wildlife……………………………………………………………………. 43

4.6         Coordination with Scientists and Ecosystem Management Agencies………………………………… 45

5.0               SENSITIVE PLANT MONITORING……………………………………………………………………….. 49

5.1         List of Sensitive Plant Species on the NNSS……………………………………………………………….. 49

5.2         Program Awareness………………………………………………………………………………………………. 53

5.3         Monitoring………………………………………………………………………………………………………….. 53

5.4         Field Surveys and Opportunistic Sightings………………………………………………………………….. 53

5.4.1            Ivesia arizonica var. saxosa, Rock Purpusia…………………………………………………………. 54

5.4.2            Arctomecon merriamii……………………………………………………………………………………. 56

5.4.3            Galium hilendiae ssp. kingstonense, Kingston Mountain bedstraw……………………………. 57

6.0               SENSITIVE AND PROTECTED/REGULATED ANIMAL MONITORING…………………….. 61

6.1         Bat Surveys…………………………………………………………………………………………………………. 61

6.1.1            Passive Acoustic Monitoring System at Camp 17 Pond………………………………………….. 61

6.1.2            Bats at Buildings……………………………………………………………………………………………. 61

6.2         Wild Horse Surveys………………………………………………………………………………………………. 61

6.2.1            Abundance…………………………………………………………………………………………………… 62

6.2.2            Annual Range Survey…………………………………………………………………………………….. 62

6.2.3            Horse Use of Water Sources…………………………………………………………………………….. 64

6.3         Mule Deer…………………………………………………………………………………………………………… 64

6.3.1            Mule Deer Abundance……………………………………………………………………………………. 64

6.3.2            Mule Deer Density…………………………………………………………………………………………. 66

6.3.3            Sex and Fawn/Doe Ratios………………………………………………………………………………… 68

6.3.4            Mule Deer Habitat Use……………………………………………………………………………………. 68

6.4         Mountain Lion Monitoring……………………………………………………………………………………… 72

Ecological Monitoring and Compliance Program 2012 Report

6.4.1            Motion-Activated Cameras………………………………………………………………………………. 72

6.4.2            Mountain Lion Telemetry Study……………………………………………………………………….. 80

6.5         Raptors and Bird Mortality……………………………………………………………………………………… 94

6.5.1            Raptors……………………………………………………………………………………………………….. 94

6.5.2            Bird Mortality and Compliance with the Migratory Bird Treaty Act………………………….. 94

6.6         Desert Bighorn Sheep and Elk Sightings…………………………………………………………………….. 96

6.7         Nuisance and Potentially Dangerous Wildlife……………………………………………………………… 97

6.8         Coordination with Biologists and Wildlife Agencies…………………………………………………….. 97

7.0               HABITAT RESTORATION MONITORING……………………………………………………………… 99

7.1         CAU 110, U-3ax/bl Closure Cover……………………………………………………………………………. 99

7.1.1            Cover………………………………………………………………………………………………………….. 99

7.1.2            Density……………………………………………………………………………………………………….. 99

7.1.3            Species Richness…………………………………………………………………………………………. 100

7.1.4            Remedial Revegetation………………………………………………………………………………….. 100

7.1.5            Summary/Recommendations………………………………………………………………………….. 101

7.2         CAU 400, Five Points Landfill……………………………………………………………………………….. 101

7.2.1            Plant Cover………………………………………………………………………………………………… 102

7.2.2            Plant Density………………………………………………………………………………………………. 102

7.2.3            Species Richness…………………………………………………………………………………………. 104

7.2.4            Revegetation Success……………………………………………………………………………………. 105

7.3         Rollercoaster RADSAFE CAU 407 Survey Results…………………………………………………….. 107

7.3.1            Plant Cover………………………………………………………………………………………………… 107

7.3.2            Plant Density………………………………………………………………………………………………. 108

7.3.3            Species Richness…………………………………………………………………………………………. 109

7.3.4            Revegetation Success……………………………………………………………………………………. 109

7.4         Control Point (CP) Waterline…………………………………………………………………………………. 109

7.5         92-Acre Site Revegetation…………………………………………………………………………………….. 110

7.5.1             Background………………………………………………………………………………………………… 110

7.5.2             Methods…………………………………………………………………………………………………….. 111

8.0               MONITORING THE NPTEC………………………………………………………………………………… 117

8.1         Task Description…………………………………………………………………………………………………. 117

8.2         Task Progress Summary……………………………………………………………………………………….. 117

9.0       REFERENCES…………………………………………………………………………………………………… 119

10.0     DISTRIBUTION………………………………………………………………………………………………… 123

Ecological Monitoring and Compliance Program 2012 Report

LIST OF FIGURES

Figure 2-1.   Biological surveys conducted on or near the NNSS during 2012…………………………………. 8

Figure 2-2.   Biological surveys conducted in important habitats of the NNSS during 2012………………. 12

Figure 3-1.   Biological surveys conducted in desert tortoise habitat on the NNSS during 2012…………. 15

Figure 3-2.   Initial desert tortoise capture locations during 2012 at the NNSS……………………………….. 18

Figure 3-3.   Desert tortoise (GOAG 3) with transmitters attached………………………………………………. 19

Figure 3-4.   Movement data collected from GPS transmitters for GOAG 4 during part of 2012………… 20

Figure 4-1.   Location of wildland fires on the NNSS during 2012……………………………………………… 27

Figure 4-2. Mean combined fuels index (top) and total precipitation for January through April (bottom) for the years 2004 to 2012……………………………………………………………………. 30

Figure 4-3.   Index of fine fuels for 106 survey stations on the NNSS during 2012…………………………. 31

Figure 4-4.   Index of woody fuels for 106 survey stations on the NNSS during 2012……………………… 32

Figure 4-5. Index of combined fine fuels and woody fuels for 106 survey stations on the NNSS during 2012…………………………………………………………………………………………………… 33

Figure 4-6.   Site 99 on the west side of Yucca Flat in 2009–2012………………………………………………. 35

Figure 4-7.   Natural water sources on the NNSS, including those monitored in 2012……………………… 40

Figure 4-8.   Hall’s Seep, a newly discovered small seep in Area 29, Topopah Valley…………………….. 42

Figure 4-9. Constructed water sources monitored for wildlife use and mortality and locations of newly installed water troughs on the NNSS during 2012…………………………………………. 44

Figure 4-10. Wild burro at water trough near Well 5C, Area 5…………………………………………………… 46

Figure 4-11. Pronghorn antelope drinking from water trough at Well 5C, Area 5…………………………… 46

Figure 4-12. Mule deer drinking from water trough near Topopah Spring…………………………………….. 47

Figure 4-13. Red-tailed hawk perched on water trough near Topopah Spring………………………………… 47

Figure 5-1.   Geographical regions on the NNSS…………………………………………………………………….. 54

Figure 5-2. Comparison of original reported location (outlined in blue) of I. arizonica var. saxosa and locations found between 2007 and 2011 (yellow) to current known distribution (brown)………………………………………………………………………………………………………… 55

Figure 5-3. Original reported locations of A. merriamii around the Mercury townsite and along Mercury Ridge in the Spotted Range (red) compared to locations added in 2012 (yellow)……………………………………………………………………………………………………….. 56

Figure 5-4.   A. merriamii in full flower along the side hills of Mercury Ridge in the Spotted Range….. 57

Figure 5-5.   Known distribution of G. hilendiae ssp. kingstonense on NNSS: original locations highlighted in red, new populations recently located highlighted in yellow………………….. 58

Figure 5-6.   Typical habitat for G. hilendiae ssp. kingstonense on the NNSS………………………………… 59

Figure 6-1.   Trends in the age structure of the NNSS horse population from 2003 to 2012………………. 62

Figure 6-2. Feral horse sightings, horse sign, and mountain lion kills observed on the NNSS

during 2012…………………………………………………………………………………………………… 63

Figure 6-3.   Road routes and sub-routes of two NNSS regions driven to count deer……………………….. 65

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-4. Trends in total deer count per night from 1989 to 2012 on the NNSS (surveys were not conducted during 1995–1998 or 2001–2005)………………………………………………………… 66

Figure 6-5.  Mean number of mule deer per 10 km per night, counted on two routes (N = number of survey nights; for 2012, N = 9)………………………………………………………………………. 67

Figure 6-6.   Mule deer observations by vegetation type on the NNSS…………………………………………. 70

Figure 6-7. Trends in significant habitat selection S > 1, and avoidance S < 1, by deer at the NNSS from 2008 to 2012 (all other points are equivalent to 1 in use)………………………………….. 71

Figure 6-8. Locations of mountain lion photographic detections (N = 22) and motion-activated cameras (N = 33) on the NNSS during 2012…………………………………………………………. 73

Figure 6-9. Number of mountain lion images by month for camera sites where mountain lions were detected from 2006 through 2012 (N = 360)………………………………………………….. 79

Figure 6-10. Number of mountain lion images by time of day (Pacific Standard Time) for camera sites where mountain lions were detected from 2006 through 2012 (N = 355)………………. 79

Figure 6-11. NNSS4 with notch in right ear, yellow ear tag in left ear, and radio collar. Also pictured is Brian Jansen…………………………………………………………………………………… 81

Figure 6-12. Documented locations of NNSS4 (May 23 to December 31, 2012)……………………………. 82

Figure 6-13. Kill site locations for NNSS4, NNSS5, NNSS6, and NNSS7 by prey type…………………… 84

Figure 6-14. Wild horse foal remains at mountain lion kill site, Area 18………………………………………. 85

Figure 6-15. NNSS5 with radio collar and orange ear tag in right ear. Also pictured is Brian Jansen…… 85

Figure 6-16. Documented locations of NNSS5 (June 3 to November 14, 2012)……………………………… 86

Figure 6-17. Pronghorn antelope kill near Gold Meadows Spring, Area 12…………………………………… 87

Figure 6-18. NNSS6 with pink ear tag in left ear and white ear tag in right ear and radio collar. Also pictured is Brian Jansen……………………………………………………………………………. 87

Figure 6-19. Documented locations of NNSS6 (June 10 to August 2, 2012)………………………………….. 88

Figure 6-20. NNSS7 captured on Timber Mountain………………………………………………………………… 89

Figure 6-21. Documented locations of NNSS7 (June 17 to December 31, 2012)……………………………. 91

Figure 6-22. Two mature bucks killed by NNSS7, Chukar Canyon (Area 30)……………………………….. 92

Figure 6-23. Recorded locations for NNSS4 (blue dots), NNSS5 (yellow dots), NNSS6 (green dots), and NNSS7 (red dots), May 23 through December 31, 2012…………………………….. 93

Figure 6-24. Historical records of reported bird deaths on the NNSS through 2012………………………… 94

Figure 6-25. Photo of red-tailed hawk nest in Area 1 retrofitted with insulation bushings (top) on electrified lines to reduce electrocution risk………………………………………………………….. 95

Figure 6-26. Desert bighorn sheep ram at Lambs Canyon Tank………………………………………………….. 97

Figure 7-1.  Perennial plant cover on the U-3 ax/bl closure cover. E. nevadensis and A. confertifolia are the most common shrubs…………………………………………………………… 102

Figure 7-2.  Overview of establishment of vegetation on the re-seeded area (foreground center) and staging area (right center) at CAU 400, Five Points Landfill……………………………… 105

Figure 7-3.   Application of Soiltac^® on the 92-Acre Site following deep ripping in April 2011……….. 111

Ecological Monitoring and Compliance Program 2012 Report

Figure 7-4.   Straw mulcher followed by tractor with Finn crimper used to secure the blown straw…… 113

Figure 7-5. Operational irrigation system composed of a central 10 cm supply line with multiple 2.5 cm lateral lines. Sprinkler heads were Nelson R2000WF Rotator^® installed on a 90 cm super stand…………………………………………………………………………………………. 114

Figure 7-6.   A young L. tridentata seedling established on the 92-Acre Site……………………………….. 115

Ecological Monitoring and Compliance Program 2012 Report

LIST OF TABLES

Table 2-1.    List of sensitive and protected/regulated species known to occur on or adjacent to

the NNSS……………………………………………………………………………………………………….. 4

Table 2-2.    Summary of biological surveys conducted on or near the NNSS during 2012………………… 9

Table 2-3.    Total area disturbed in hectares within important habitats in 2012 and cumulative over the past 12 years……………………………………………………………………………………… 11

Table 3-1.    Summary of tortoise compliance activities conducted by site biologists during 2012……… 14

Table 3-2.    Cumulative incidental take (2009–2012) and maximum allowed take for NNSA/NFO programs………………………………………………………………………………………………………. 16

Table 3-3.    Data on desert tortoises captured for the NNSS road study during 2012………………………. 19

Table 3-4.    Traffic counter data for the ten locations on NNSS roads within desert tortoise habitat.

Values are the number of vehicle passes in the 2-week period…………………………………… 22

Table 4-1.    Number and area of wildland fires on the NNSS, 1978–2012……………………………………. 25

Table 4-2.    Date, location, acreage, and cause of wildland fires on the NNSS in 2012…………………… 26

Table 4-3.    Woody fuels, fine fuels and combined fuels index values for 2004–2012…………………….. 29

Table 4-4.    Precipitation history and percent presence of key plant species contributing to fine fuels at 106 surveyed sites………………………………………………………………………………… 36

Table 4-5.    Results of West Nile virus surveillance on the NNSS in 2012…………………………………… 37

Table 4-6.    Hydrology and disturbance data recorded at natural water sources on the NNSS

during 2012…………………………………………………………………………………………………… 39

Table 4-7.    Number of wildlife species observed or inferred (P = Present) at NNSS natural

water sources in 2012……………………………………………………………………………………… 41

Table 4-8.    New water sources detected during mountain lion monitoring in 2011–12 on the NNSS…. 42

Table 4-9.    Results of monitoring plastic-lined sumps for wildlife mortality on the NNSS for 2012….. 45

Table 5-1.    Criteria used in ranking sensitive plants known to occur on the NNSS……………………….. 51

Table 5-2.    Ranking of sensitive plants known to occur on the NNSS………………………………………… 52

Table 6-1.    Deer density estimates, confidence intervals, and other parameters for two routes and

sub-routes of the NNSS for 2012 using Program DISTANCE software………………………. 68

Table 6-2.    Mule deer sex ratios, fawns, and fawn to doe ratios across years on the NNSS……………… 68

Table 6-3.    Habitat use index, W_i, from spotlighted mule deer on the NNSS during 2012………………. 69

Table 6-4.    Results of mountain lion camera surveys during 2012…………………………………………….. 74

Table 6-5.    Number of mountain lion images taken with camera traps by month, location, and animal number, if known…………………………………………………………………………………. 78

Table 7-1.    Percent plant cover and density (plants/m²) on the U-3ax/bl closure cover in 2012. The success standard represents 70% of the cover or density reported for the reference area………………………………………………………………………………………………… 99

Table 7-2.    Average species richness for the closure cover and reference site in 2012. Species richness is defined as the average number of different species found within a m² quadrat……………………………………………………………………………………………………….. 100

Ecological Monitoring and Compliance Program 2012 Report

Table 7-3.    Percent plant cover on CAU 400, Five Points Landfill…………………………………………… 103

Table 7-4.    Plant density (plants per m²) on CAU 400, Five Points Landfill………………………………. 104

Table 7-5.    Species richness (species per m² quadrat) on CAU 400, Five Points Landfill………………. 104

Table 7-6.    Percent plant cover on CAU 407, Rollercoaster RADSAFE closure cover…………………. 107

Table 7-7.    Plant Density (Plants per m²) on CAU 407…………………………………………………………. 108

Table 7-8.    Species Richness (Species per m²) on CAU 407…………………………………………………… 109

Table 7-9.    Density (plants/m²) of seeded species on the CP Waterline in Area 6 of the NNSS………. 110

Table 7-10.  Plant species included in seed mix and seeding rates (Pure Live Seed [PLS]), including a 10% contingency, for each species used to seed the 92-Acre Site……………… 112

Table 7-11. Amount of natural and supplemental water (mm) applied to 92-Acre revegetation site from January to December 2012………………………………………………………………………. 114

Ecological Monitoring and Compliance Program 2012 Report

Ecological Monitoring and Compliance Program 2012 Report

ACRONYMS AND ABBREVIATIONS

AIC                           Akaike’s Information Criterion

CAU                         Corrective Action Unit

CI                             Confidence Interval

cm                            centimeter(s)

CORA-EPNE             Coleogyne ramosissima–Ephedra nevadensis Shrubland CP            Control Point

DAF                          Device Assembly Facility

DOE/NV                   U.S. Department of Energy, Nevada Operations Office EEM       Ecological and Environmental Monitoring

ELU                          Ecological Landform Unit

EM                            Environmental Monitor

EMAC                      Ecological Monitoring and Compliance Program

ESA                          Endangered Species Act

ESW                         Effective Strip Width

FWS                          U.S. Fish and Wildlife Service

FY                            fiscal year

g                               gram(s)

GIS                           Geographic Information System

GPS                          Global Positioning System

ha                             hectare(s)

ICR                           San Diego Zoo Institute for Conservation Research

kg                             kilogram(s)

km                            kilometer(s)

km²                           square kilometer(s)

LANL                       Los Alamos National Laboratory

m                              meter(s)

m²                             square meter(s)

MCL                         Midline carapace length

mm                           millimeter(s)

N                              Sample Size

NAC                         Nevada Administrative Code

NNHP                       Nevada Natural Heritage Program

NNPS                        Nevada Native Plant Society

Ecological Monitoring and Compliance Program 2012 Report

ACRONYMS AND ABBREVIATIONS (continued)

NNSA/NFO              U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office

NNSS                        Nevada National Security Site

NOAA                      National Oceanic and Atmospheric Administration

NPTEC                     Nonproliferation Test and Evaluation Complex

NSTec                       National Security Technologies, LLC

NTTR                       Nevada Test and Training Range

pCi/L                        picocurie(s) per liter

PIMO/ARNO             Pinus monophylla/Artemisa nova Woodland PIMO/ARTR      Pinus monophylla/Artemisa tridentata Woodland PLS    Pure Live Seed

RNCTEC                  Radiological/Nuclear Countermeasures Test and Evaluation Complex RWMC      Radioactive Waste Management Complex

SNHD                       Southern Nevada Health District

SOC                          Special Operations Center

spp.                           species

ssp.                           subspecies

TBD                          To be determined

TTR                          Tonopah Test Range

USGS                        U.S. Geological Survey

var.                           variety

VHF                          Very High Frequency

W_i                             habitat use index

WNV                        West Nile Virus

xiv

Ecological Monitoring and Compliance Program 2012 Report

1.0    INTRODUCTION

In accordance with U.S. Department of Energy Order DOE O 231.1B, “Environment, Safety, and Health Reporting,” the Office of the Assistant Manager for Environmental Management of the U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office (NNSA/NFO, formerly Nevada Site Office) requires ecological monitoring and biological compliance support for activities and programs conducted at the Nevada National Security Site (NNSS). National Security Technologies, LLC (NSTec), Ecological and Environmental Monitoring (EEM) has implemented the Ecological Monitoring and Compliance Program (EMAC) to provide this support. EMAC is designed to ensure compliance with applicable laws and regulations, delineate and define NNSS ecosystems, and provide ecological information that can be used to predict and evaluate the potential impacts of proposed projects and programs on those ecosystems. During 2012, all applicable laws, regulations, and permit requirements were met, enabling EMAC to achieve its intended goals and objectives.

This report summarizes the EMAC activities conducted by NSTec during calendar year 2012. Monitoring tasks during 2012 included seven program areas: (a) biological surveys, (b) desert tortoise compliance,

(c) ecosystem monitoring, (d) sensitive plant monitoring, (e) sensitive and protected/regulated animal monitoring, (f) habitat restoration monitoring, and (g) biological monitoring at the Nonproliferation Test and Evaluation Complex (NPTEC). The following sections of this report describe work performed under these seven areas.

Ecological Monitoring and Compliance Program 2012 Report

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Ecological Monitoring and Compliance Program 2012 Report

2.0            BIOLOGICAL SURVEYS

Biological surveys are performed at project sites where land-disturbing activities are proposed. The goal is to minimize adverse effects of land disturbance on sensitive and protected/regulated plant and animal species (Table 2-1), their associated habitat, and other important biological resources. Sensitive species are defined as species that are at risk of extinction or serious decline or whose long-term viability has been identified as a concern. They include species on the Nevada Natural Heritage Program (NNHP) Animal and Plant At-Risk Tracking List (NNHP 2013) and bat species ranked as moderate or high in the Revised Nevada Bat Conservation Plan Bat Species Risk Assessment (Bradley et al. 2006).

Protected/regulated species are those that are protected or regulated by federal or state law. Many species are both sensitive and protected/regulated (Table 2-1). Important biological resources include cover sites, nest or burrow sites, roost sites, or water sources important to sensitive species. Survey reports document species and resources found and provide mitigation recommendations.

2.1             Sites Surveyed and Sensitive and Protected/Regulated Species Observed

During 2012, biological surveys for 18 projects were conducted on the NNSS (Figure 2-1 and Table 2-2). Two surveys were conducted off the NNSS (Table 2-2). One project had multiple site locations. Scientists surveyed a total of 145.17 hectares (ha) for the projects (Table 2-2). Fifteen projects were within the range of the threatened desert tortoise (Gopherus agassizii). Sensitive and protected/regulated species and important biological resources found included Joshua trees (Yucca brevifolia) and cacti (Table 2-2).

NSTec provided written summary reports to project managers of survey findings and mitigation recommendations, where applicable (Table 2-2).

2.2             Potential Habitat Disturbance

Surveys are conducted for all activities that would disturb habitat, including new projects, routine maintenance activities, or cleanup activities at old industrial or nuclear weapons testing sites. These surveys are required whenever vegetation has re-colonized old disturbances and sensitive or protected/regulated species are known to occur in the area. For example, desert tortoises may move through revegetated earthen sumps and may be concealed under vegetation during activities where heavy equipment is used. Biological surveys and tortoise clearance surveys are conducted to ensure that desert tortoises are not in harm’s way. Burrowing owls frequently inhabit burrows and culverts at disturbed sites, so surveys are conducted to ensure that adults, eggs, and nestlings are not harmed.

Of the 20 projects surveyed, 15 were within sites previously disturbed (e.g., road shoulders, old building sites, industrial waste sites, or existing well pads) (Table 2-2). Five projects were located totally or partially in areas that had not been previously disturbed. These projects could potentially disturb 7.59 ha of land that were previously considered undisturbed (some projects have been proposed, but the construction activity has not yet occurred). Two projects occurred in areas designated as important habitats (Table 2-3 and Figure 2-2). During vegetation mapping of the NNSS (Ostler et al. 2000), Ecological Landform Units (ELUs) were evaluated for importance. Some ELUs were identified as Pristine Habitat (having few man-made disturbances), Unique Habitat (containing uncommon biological resources such as a natural wetland), Sensitive Habitat (containing vegetation associations that recover very slowly from direct disturbance or are susceptible to erosion), and Diverse Habitat (having high plant species diversity) (U.S. Department of Energy, Nevada Operations Office [DOE/NV] 1998). A single ELU could be classified as more than one type of these four types of important habitats.

Ecological Monitoring and Compliance Program 2012 Report

Table 2-1. List of sensitive and protected/regulated species known to occur on or adjacent to the NNSS

Penstemon fruticiformis ssp. amargosae

Death Valley beardtongue                  S, H

Penstemon pahutensis                             Pahute Mesa beardtongue                  S, W

Phacelia beatleyae                                 Beatley scorpionflower                      S, M

Phacelia filiae                                        Clarke phacelia                                 S, M

Phacelia mustelina                                 Weasel phacelia                                S, Ma

Agavaceae                                             Yucca (3 species),

Agave (1 species)

Cactaceae                                              Cacti (18 species)                              CY

Juniperus osteosperma                           Juniper                                              CY

Pinus monophylla                                   Pinyon                                              CY

Ecological Monitoring and Compliance Program 2012 Report

Table 2-1. List of sensitive and protected/regulated species known to occur on or adjacent to the NNSS (continued)

Ecological Monitoring and Compliance Program 2012 Report

Table 2-1. List of sensitive and protected/regulated species known to occur on or adjacent to the NNSS (continued)

^aStatus Codes:

Endangered Species Act, U.S. Fish and Wildlife Service LT – Listed Threatened

C        – Candidate for listing

U.S. Department of Interior

H&B – Protected under Wild Free Roaming Horses and Burros Act

EA      – Protected under Bald and Golden Eagle Act

State of Nevada – Animals

S         – Nevada Natural Heritage Program – Animal and Plant At Risk Tracking List

NPE – Nevada Protected-Endangered, species protected under Nevada Administrative Code (NAC) 503 NPT – Nevada Protected-Threatened, species protected under NAC 503

NPS – Nevada Protected-Sensitive, species protected under NAC 503

Ecological Monitoring and Compliance Program 2012 Report

Table 2-1. List of sensitive and protected/regulated species known to occur on or adjacent to the NNSS (continued)

NP      – Nevada Protected, species protected under NAC 503 G               – Regulated as game species under NAC 503

F         – Regulated as fur-bearer species under NAC 503

State of Nevada – Plants

S         – Nevada Natural Heritage Program – Animal and Plant At-Risk Tracking List CY     – Protected as a cactus, yucca, or Christmas tree

NNSS Sensitive Plant Ranking H – High

M       – Moderate

W       –  Watch Ma     – Marginal

Long-term Animal Monitoring Status for the NNSS A              – Active

IA      – Inactive

The Revised Nevada Bat Conservation Plan – Bat Species Risk Assessment H           – High

M       – Moderate

^bAll bird species on the NNSS are protected by the Migratory Bird Treaty Act except for chukar, Gambel’s quail, English house sparrow, Rock dove, and European starling.

Sources used: NNHP 2013, Nevada Native Plant Society (NNPS) 2013, NAC 2013, U.S. Fish and Wildlife Service (FWS) 2013, Bradley et al. 2006

Ecological Monitoring and Compliance Program 2012 Report

Figure 2-1.    Biological surveys conducted on or near the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Table 2-2. Summary of biological surveys conducted on or near the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Table 2-2. Summary of biological surveys conducted on or near the NNSS during 2012 (continued)

*Project not completed, actual area may vary. EM – Environmental Monitor

RNCTEC – Radiological/Nuclear Countermeasures Test and Evaluation Complex TCS – Tortoise Clearance Survey

Ecological Monitoring and Compliance Program 2012 Report

Table 2-3. Total area disturbed in hectares within important habitats in 2012 and cumulative over the past 12 years

Figure 2-2 shows the distribution of these important habitats, ranked so that pristine habitat overlays unique habitat, which then overlays sensitive habitat, which then overlays diverse habitat. The expected area disturbed in important habitats due to 2012 projects is 5.29 ha (Table 2-3). Since 1999, the total area of important habitat disturbed by NNSA/NFO activities is 450.40 ha. This tally is used to document the loss of important habitat.

Ecological Monitoring and Compliance Program 2012 Report

Figure 2-2. Biological surveys conducted in important habitats of the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

3.0            DESERT TORTOISE COMPLIANCE

Desert tortoises occur within the southern one-third of the NNSS. This species is listed as threatened under the Endangered Species Act (ESA). In December 1995, NNSA/NFO completed consultation with the U.S. Fish and Wildlife Service (FWS) concerning the effects of NNSA/NFO activities, as described in the Final Environmental Impact Statement for the Nevada Test Site and Off-Site Locations in the State of Nevada (DOE/NV 1996), on the desert tortoise. NNSA/NFO received a final Biological Opinion (Opinion) from FWS in August 1996 (FWS 1996). On July 2, 2008, NNSA/NFO provided FWS with a Biological Assessment of anticipated activities on the NNSS for the next 10 years and entered into formal consultation with FWS to obtain a new Opinion for the NNSS. NNSA/NFO received the final Opinion on February 12, 2009 (FWS 2009). This Opinion covers the anticipated activities at the NNSS until 2019.

The Desert Tortoise Compliance task of EMAC implements the terms and conditions of the 2009 Opinion, documents compliance actions taken by NNSA/NFO, and assists NNSA/NFO in FWS consultations. All of the terms and conditions listed in the Opinion were implemented by NSTec staff biologists in 2012, including (a) conducting clearance surveys at project sites within 1 day from the start of project construction, (b) ensuring that project managers have environmental monitors on site during site clearing and heavy equipment operation, (c) developing effects analysis for proposed disturbances to append to the Opinion, and (d) preparing an annual compliance report for NNSA/NFO submittal to the FWS.

3.1             Project Surveys and Compliance Documentation

During 2012, biologists conducted desert tortoise clearance surveys prior to ground-disturbing activities for 13 proposed projects within the range of the desert tortoise on the NNSS. Two other projects have been submitted to FWS for approval to append to our Opinion (Table 3-1 and Figure 3-1). Two projects were located off the NNSS; after reviewing the projects, it was determined that they would not impact desert tortoises, so they were not included in this section. Most of these projects were in, or immediately adjacent to, roads, existing facilities, or other disturbances. No desert tortoises were observed in project areas, and six tortoise burrows found during tortoise clearance surveys were flagged (Project No. 11-34). Three of the burrows were scoped and collapsed because they were within the project area and could not be avoided. The other three burrows were blocked during the project activities.

Four projects were initiated that disturbed previously undisturbed desert tortoise habitat. Projects 11-37, 12-04, 12-22, and 12-23 disturbed 6.17 ha of desert tortoise habitat in 2012 (Table 3-1). The Substation expansion and power line (11-37) resulted in a loss of 0.32 ha. The anticipated loss for this project was

0.38 ha, and a mitigation fee of $769.50 was paid on July 16, 2012. The Radiological/Nuclear Countermeasures Test and Evaluation Complex (RNCTEC) Expansion – security ditch and spoils pile

(12-04) disturbed 5.01 ha of ground. The power line for Device Assembly Facility (DAF) barriers (12-22) disturbed 0.28 ha, which was less than the 0.56 ha approved by the Service. The mitigation fee of

$1,117.80 was paid on November 1, 2012. The fourth project, RNCTEC Expansion – conex pad (12-23), disturbed 0.56 ha. Payment for all of the RNCTEC Expansion projects was made in 2011.

Post-activity surveys to quantify the acreage of tortoise habitat actually disturbed were conducted for 13 projects during this reporting period (Table 3-1). All projects stayed within proposed project

boundaries. Post-activity surveys are generally not conducted if the projects are located within previously disturbed areas or if the environmental monitor documented that the project stayed within its proposed boundaries.

Ecological Monitoring and Compliance Program 2012 Report

Table 3-1. Summary of tortoise compliance activities conducted by site biologists during 2012

Project                                    Project

Number

Compliance  Activities 100% Coverage Clearance Survey

Tortoise Habitat Disturbed

(Ha)

11-34       BREN Tower removal                                           Yes, post-activity survey completed                     0

11-37       Substation expansion and power line                 Yes, post-activity survey completed                   0.32

12-01       Corrective Action Unit 562                                    Yes, post-activity survey completed                     0

12-04       RNCTEC Expansion (Security ditch and

Yes, post-activity survey completed                   5.01

TBD = to be determined

Ecological Monitoring and Compliance Program 2012 Report

Figure 3-1. Biological surveys conducted in desert tortoise habitat on the NNSS during 2012

15

Ecological Monitoring and Compliance Program 2012 Report

In January 2012, the annual report that summarized tortoise compliance activities conducted on the NNSS from January 1 through December 31, 2011, was submitted to the FWS. This report, required under the Opinion, contains (a) the location and size of land disturbances that occurred within the range of the desert tortoise during the reporting period; (b) the number of desert tortoises injured, killed, or removed from project sites; (c) a map showing the location of all tortoises sighted on or near roads on the NNSS; and (d) a summary of construction mitigation and monitoring efforts.

Compliance with the Opinion ensures that the desert tortoise is protected on the NNSS and that the cumulative impacts on this species are minimized (DOE/NV 1998). In the Opinion, the FWS determined that the “incidental take” of tortoises on the NNSS and the cumulative acreage of tortoise habitat disturbed on the NNSS are parameters that should be measured and monitored annually. During this calendar year, the threshold levels established by the FWS for these parameters were not exceeded (Table 3-2). No desert tortoises were accidentally injured or killed by project activities. One desert tortoise was injured by a vehicle along Jackass Flats road in Area 25 in 2012. The tortoise walked away from the site, so the injury did not appear to be life-threatening. Seven tortoises were removed from roads to avoid being killed or injured and are reported in the “Other” column of Table 3-2. Eleven desert tortoises were captured as part of the road mitigation study on the NNSS and transmitters were attached so their movements could be tracked. This brings the total number of tortoises taken under the “Other” category to 45 for the 4 years under the current Opinion.

Table 3-2. Cumulative incidental take (2009–2012) and maximum allowed take for NNSA/NFO programs

*One project is not yet completed but is anticipated to disturb 42.2 hectares. The actual amount disturbed will be reported in the 2013 report.

Ecological Monitoring and Compliance Program 2012 Report

3.2         Mitigation for Loss of Tortoise Habitat

Mitigation for the loss of tortoise habitat is required under the terms and conditions of the Opinion. The Opinion requires NNSA/NFO to perform one of two mitigation options: (a) prepay funds into the Desert Tortoise Mitigation Funds (current 2012 rate is $2,000.70 per ha of habitat disturbed), or (b) prepay mitigation funds at the current rate, then revegetate disturbed habitat following specified criteria; once the revegetation is successful, the money paid for mitigation will be refunded. Three projects (11-34, 11-37, and 12-22) paid a total of $2,818.80 into the Desert Tortoise Mitigation Fund to mitigate the 0.60 ha of land that was disturbed in 2012. The other 5.57 ha disturbed as part of the RNCTEC Expansion were paid for in 2011.

3.3         Conservation Recommendation Studies

One of the conservation recommendations of the Opinion (FWS 2009) states that NNSA/NFO:

should develop a strategy to minimize road mortalities on the NNSS by focusing efforts on roads that have a history of mortality or that traverse higher density desert tortoise areas (page 29 of the Opinion).

In order to address this conservation recommendation, results from prior desert tortoise surveys and historic roadside observation/mortality data were analyzed using a Geographic Information System (GIS) to identify areas with higher densities of desert tortoises and areas that may be at higher risk for tortoise mortalities caused by vehicles along NNSS roads. This analysis suggested a need for a better understanding of desert tortoise activity near roads with high desert tortoise use and the effects of the zone of depression (up to ¼ mile) on tortoise abundance in order to better develop the strategy to minimize road mortalities.

Desert tortoises may be drawn to roads to forage and drink, especially after summer rains when water collects in depressions on or along roads, thus creating a short-term source of drinking water that may be critical to their survival. Further, roadside vegetation is typically more succulent than non-roadside vegetation due to a water-harvesting effect and roadside maintenance activities such as mowing or blading, which typically stimulates plant growth. In addition, while some efforts to model desert tortoise habitat in the Mojave Desert have been made (Weinstein 1989, Andersen et al. 2000, Nussear et al. 2009), knowledge about fine-scale patterns of habitat use is still lacking.

3.3.1        Road Study

In 2010, NNSA/NFO began talks with the FWS and personnel from San Diego Zoo’s Institute for Conservation Research (ICR) to assess research that may assist NNSA/NFO in reducing or mitigating desert tortoise take on roads. On March 15, 2012, NNSA/NFO requested FWS to approve a research plan to assess desert tortoise movements near roads on the NNSS. On April 13, 2012, FWS appended this action to the Opinion, which allows NNSA/NFO authorized biologists to place transmitters on up to 20 desert tortoises found near roads and study their movements through 2014. The main objectives of this study are to (a) determine fine-scale patterns of habitat use of desert tortoises found near roads on the NNSS, and (b) assess the risk of desert tortoise road mortality on the NNSS. A secondary objective is to assess the health and condition of desert tortoises on the northern periphery of their range.

A total of 11 desert tortoises (4 males and 7 females) were captured on or near roads on the NNSS during 2012 (Figure 3-2). Global Positioning System (GPS) and Very High Frequency (VHF) transmitters were attached to their carapaces or shells by trained personnel following approved protocols (Figure 3-3).

Ecological Monitoring and Compliance Program 2012 Report

Figure 3-2.   Initial desert tortoise capture locations during 2012 at the NNSS

Ecological Monitoring and Compliance Program 2012 Report

Figure 3-3.   Desert tortoise (GOAG 3) with transmitters attached

(Photo taken by D. B. Hall, May 17, 2012)

Seven of the tortoises were captured as a result of opportunistic observations along roads. One tortoise, designated as GOAG 6, was captured when biologists walked transects adjacent to paved roads, and three tortoises (GOAG 7, 9, and 10) were found while conducting routine telemetry to determine tortoise locations. Table 3-3 provides information on the captured tortoises.

Table 3-3. Data on desert tortoises captured for the NNSS road study during 2012

Ecological Monitoring and Compliance Program 2012 Report

GPS transmitters were generally set to record data every 15 minutes during daylight hours. Tortoises were tracked via VHF transmitter generally once a week. GPS transmitters were changed out every 1–2 months (depending on battery life and tortoise accessibility) during the active season. During early October, GPS units were changed to record data only three times a day (1000, 1200, and 1400) for the inactive season.

An initial body size and health evaluation was performed on each tortoise when it was captured. This included weight, midline carapace length (MCL), width, height, body condition, shell abnormalities, skin lesions, respiration, and nares and eye assessments for discharge. On July 16, 2012, formal health evaluations including a blood sample for disease testing was conducted on several tortoises by trained personnel from the ICR. Because of time/temperature constraints, only seven tortoises received this evaluation and disease testing.

The processing and analysis of data from the GPS transmitters attached to the tortoises is ongoing. An example of movement patterns of GOAG 4 are shown in Figure 3-3. Tortoise locations for this figure are in 15-minute increments during daylight hours starting on May 24 and continuing through July 31, 2012.

Figure 3-4.   Movement data collected from GPS transmitters for GOAG 4 during part of 2012

Ecological Monitoring and Compliance Program 2012 Report

3.3.2        Traffic Counters

Ten traffic counters were placed on major roads within desert tortoise habitat on the NNSS in 2012 (Table 3-4). Traffic counters were checked every 2 weeks, and the number of vehicle passes was recorded. Traffic counts were initiated on April 2, 2012, and continued for 26 weeks. The traffic counters were removed on October 16, 2012. Not all of the traffic counters functioned properly over that 6-month period. In some instances, missing data could be estimated from counts along other road segments. When this was not possible, the missing data were omitted from the analysis. Traffic volumes are reported in Table 3-4. Mercury Highway 200 Hill location had the highest daily passes at 647.0 vehicles per day.

H Road had the least number of passes at 15.5 per day. Traffic volumes on roads varied a great deal between road segments but not as much seasonally on any individual road segment. There appears to be four natural clusters of road segments based on traffic volume. The most traffic was recorded on the two segments of the Mercury Highway (Frenchman Flats and 200 Hill), which averaged 601 passes per day. The second cluster is a single segment (Jackass Flats Road) with 136 passes per day, which was roughly one-quarter of the daily passes as Mercury Highway. The third cluster consisted of four road segments (Area 27 Road, Rock Valley, Cane Spring east, and 5-01 Road), which averaged 76 passes per day, which was roughly one-half the volume of Jackass Flats Road. The final cluster of three segments averaged

22 passes per day, which was roughly one-third the volume of the third cluster.

3.4         Coordination with Other Biologists and Wildlife Agencies

During February 17–19, 2012, an NSTec biologist attended the Desert Tortoise Council’s 37^th annual meeting and symposium. This meeting was held in Las Vegas, Nevada, and included numerous presentations on desert tortoise biology, ecology, and recovery efforts.

Several times during the spring of 2012, NSTec biologists were trained at the Desert Tortoise Conservation Center in various tortoise handling procedures, including how to attach and remove transmitters. On April 3, 2012, five NSTec scientists attended the FWS lecture on tortoise handling and biosecurity as part of the health assessment training. One NSTec scientist received the entire health assessment training.

During 2012, NSTec scientists assisted ICR personnel in setting up a research study to investigate the survival of translocated juvenile desert tortoises. Translocation sites were selected on the NNSS in

Area 22. On September 19, 2012, 60 juvenile tortoises were released. Each tortoise had a VHF transmitter attached to its shell and was tracked daily for the first week following release and weekly thereafter by ICR personnel.

Ecological Monitoring and Compliance Program 2012 Report

Table 3-4. Traffic counter data for the ten locations on NNSS roads within desert tortoise habitat.

Values are the number of vehicle passes in the 2-week period.

Ecological Monitoring and Compliance Program 2012 Report

4.0            ECOSYSTEM MONITORING

Ecological Services began comprehensive mapping of plant communities and wildlife habitat on the NNSS in 1996. Data were collected, describing selected biotic and abiotic habitat features within field mapping units called ELUs. ELUs are landforms (Peterson 1981) with similar vegetation, soil, slope, and hydrology. Boundaries of the ELUs were defined using aerial photographs, satellite imagery, and field confirmation. ELUs are considered by site biologists to be the most feasible mapping unit by which sensitive plant and animal habitats can be described. In 2000 and 2001, topical reports describing the classification of vegetation types on the NNSS were published and distributed (Ostler et al. 2000, Wills and Ostler 2001). Ten vegetation alliances and 20 associations were reported to occur on the NNSS.

Efforts are made to update and collect new habitat data when possible. Efforts during 2012 focused on the following tasks in support of ecosystem monitoring:

• Wildland fire fuels surveys – A vegetation survey was conducted in the spring to determine wildland fire hazards due to the accumulation of woody and fine fuels.
• West Nile virus (WNV) surveillance – Fifteen surveys at seven sites were conducted to detect WNV.
• Reptile Sampling– Trapping occurred at more than 20 sites to try to capture uncommon snakes and lizards and fill in data gaps in reptile distributions.
• Natural wetlands monitoring – Seventeen natural wetlands were monitored in 2012.
• Constructed water source monitoring – Twenty-three sites containing constructed water sources were monitored in 2012, and five water troughs were installed at various sites to help mitigate the loss of well ponds.
• Offsite coordination – NSTec biologists coordinated with ecosystem management agencies and scientists.

4.1             Vegetation Survey for Wildland Fire Hazard Assessment

Wildland fires on the NNSS require considerable financial resources for fire suppression and mitigation. For example, costs for fire suppression on or near the NNSS can cost as much as $198 per hectare (Hansen and Ostler 2004). Costs incurred from the Egg Point Fire in August 2002 (121 ha) were well over $1 million to replace 1 mile of burned power poles, and more than $200,000 for soil stabilization and revegetation of the burned area.

From 1978 until 2012, there has been an average of 11.7 wildland fires per year on the NNSS with an average of about 84.6 ha burned per fire (Table 4-1). Historically most wildland fires are caused by lightning and do not occur randomly across the NNSS, but occur more often in particular vegetation types (e.g., blackbrush [Coleogyne ramosissima] plant communities). These types have sufficient woody and fine-textured fuels that are conducive to ignition and spread of wildland fires. Once a site burns, it is much more likely to burn again because of the invasive annual plants that quickly colonize these areas (Brooks and Lusk 2008).

The year 2012 was considered normal for wildland fires, with 11 wildland fires on the NNSS. Seven fires were caused by lightning, burning a total of 206.0 ha; two fires were caused by ordnance for a total of

6.5 ha; one fire was caused by high winds, burning 4 ha; and one was caused by a vehicle, which burned about 0.4 ha (Table 4-2). Fire names were assigned by the first firefighter to arrive at a fire. Some fires are unnamed except for the name of the general area. Locations of fires on the NNSS in 2012 are shown

Ecological Monitoring and Compliance Program 2012 Report

in Figure 4-1. Not all fires had their perimeters mapped because they were inaccessible due to rugged terrain or lacked post-fire aerial photography to determine the GPS coordinates of the fire perimeter.

Beginning in 2004, and in response to DOE O 231.1B, surveys were initiated on the NNSS to identify wildland fire hazards. Vegetation surveys were conducted in April and May 2012 at sites located along and adjacent to major NNSS corridors to estimate the abundance of fuels produced by native and invasive plants. Information about climate and wildland fire-related information reported by other government agencies was also identified and summarized as part of the wildland fire hazards assessment. Survey findings and fuels assessment maps were compiled and reported to NNSS Fire and Rescue Department.

4.1.1        Survey Methods

The abundance of fine-textured (grasses and herbs) and coarse-textured (woody) fuels were visually estimated on numerical scales using an 11-point potential scale: 0 to 5 (in 0.5 increments, where 0.0 is barren and 5.0 is near maximum biomass encountered on the NNSS). Details of the methodology used to conduct the spring survey for assessing wildland fire hazards on the NNSS are described in a report by Hansen and Ostler (2004).

Photographs of sites typifying these different scale values are found in Appendix A of the Ecological Monitoring and Compliance Program Calendar Year 2005 Report (Bechtel Nevada 2006). Additionally, the numerical abundance rating for fine fuels at a site was added to the numerical abundance rating of woody fuels to derive a combined fuels rating for each site that ranged from 0 to 10 in one-half integer increments. The index ratings for fuels at these survey sites were then plotted on a GIS map and color- coded for abundance to indicate the wildland fire fuel hazards at various locations across the NNSS.

Ecological Monitoring and Compliance Program 2012 Report

Table 4-1. Number and area of wildland fires on the NNSS, 1978–2012

Source: Hall (2013)

Ecological Monitoring and Compliance Program 2012 Report

Table 4-2. Date, location, acreage, and cause of wildland fires on the NNSS in 2012

Figure 4-1.   Location of wildland fires on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

4.1.2        Survey Results

4.1.2.1       Climate

There are 17 rain gauges on the NNSS (Hansen and Ostler 2004) that have been used historically to measure precipitation. Data from these weather station gauges extends back more than 30 years (National Oceanic and Atmospheric Administration [NOAA] 2011). In the fall of 2011, most of the rain gauges on the NNSS were upgraded from weighing gauges to tipping-bucket style gauges with data transmitted directly to NOAA via telecommunications, rather than manually retrieving and processing the data (Hansen 2012). In most cases, the new gauges were relocated nearby to facilitate data collection. The changes were made to reduce costs, improve data reliability, and improve access time to the data after precipitation events. As a result of these modifications, only 13 rain gauges remain from the original gauge stations. The Cane Spring, Tippipah Spring, Little Feller 2, and Rock Valley gauge stations were decommissioned. The Jackass Flats gauge was moved to Port Gaston in Area 26. The rain gauge at

Mid Valley was not functional during the month of March, and the rain gauge at Port Gaston was not functional during the month of April. Precipitation data collected in 2012 reflect these changes and attempt to match, as closely as possible, data collected historically. Mean values were recalculated to account for months when gauges were not functional.

In order to determine whether the spring of the year was a relatively wet, normal, or a dry year, a simple measure of precipitation was needed. Precipitation during the months of January, February, March, and April was selected because of its simplicity and ease of calculation. While it is recognized that precipitation from other months is also important (and in some cases may be more important), as is the influence of temperature, winds, and relative humidity, these months represent the period of most plant growth observed along the survey route during the spring and before the beginning of the fire season in June. During many years, the mean precipitation during these 4 months appears to be correlated with production of vegetation that produces most fine and some woody fuels. The total accumulated precipitation during this period was observed to be correlated with fine fuels biomass production during this winter/spring period as reported by Hansen and Ostler (2004).

During 2012, the average precipitation from the remaining 13 rain gauges of the original 17 rain gauge stations on the NNSS during January–April was 4.01 centimeters (cm), or about 45.8% of the normal amount (i.e., the average precipitation for the last 30 years—8.86 cm). Temperatures were also cooler than normal during these months.

4.1.2.2       Fuels

Because of the below-normal precipitation that occurred during the spring of 2012, few annual or perennial plant seeds germinated. Even perennial herbaceous grasses and forbs had little, if any, production during the spring of 2012.

There was a decrease in the woody fuels index value in 2012 (2.43) compared to 2011 (2.58), as foliar canopy cover decreased slightly (Table 4-3). This was the lowest ranking since 2004 when index values were initiated. The fine fuels index also decreased in 2012 (1.75) compared to 2011 (2.56), ranking the second lowest since 2004 (Table 4-3).

Ecological Monitoring and Compliance Program 2012 Report

Table 4-3. Woody fuels, fine fuels and combined fuels index values for 2004–2012

The combined index values (fine fuels plus woody fuels) for 2012 corresponds to the potential for fuels on the NNSS to support wildland fires once fuels are ignited. The higher the index, the greater the potential for wildland fires to spread. The NNSS average combined index value for fine fuels and woody fuels for 2012 was 4.17, the second lowest since 2004 (Table 4-3), suggesting below normal fuels for the NNSS. However, most fuels in the spring of 2012 appeared to be well cured and highly susceptible to ignition due to the low moisture content in the residual fuels and the low relative humidity of air from the below-normal precipitation on the NNSS.

The fine fuels documented during the spring of 2012 were predominantly remnants of plant growth formed during the spring of 2011. It was estimated that about 40% of the fine fuels produced during 2011 persisted into the spring of 2012. This percentage appears to be high compared to years with more precipitation (e.g., about 30% residual fuels). Precipitation aids in the decomposition and weathering of the fuels.

Figure 4-2 shows a comparison in trends of mean precipitation and mean combined fuel index values. The droughts of 2007 and 2012 significantly reduced fine fuels and to a lesser extent woody fuels. The locations and results of the fine fuels, woody fuels and combined fuels surveys at 106 stations on the NNSS inspected during 2012 are shown in Figures 4-3, 4-4, and 4-5, respectively. High combined index values occurred in Fortymile Canyon and Big Burn Valley.

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-2.    Mean combined fuels index (top) and total precipitation for January through April (bottom) for the years 2004 to 2012

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-3.   Index of fine fuels for 106 survey stations on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-4.   Index of woody fuels for 106 survey stations on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-5.   Index of combined fine fuels and woody fuels for 106 survey stations on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Photographs were taken from permanent locations for all 106 sites during the past 8 years. Figure 4-6 shows photographs of Site 99 in Yucca Flat for the last 4 years. These photographs are valuable for many reasons, including providing a permanent record of previous site conditions, comparing site conditions among sites and years, and evaluating current year production with residual fuels from previous years.

As in past years, sites dominated by blackbrush and annual grasses appeared to respond to precipitation with greater variation in the amount of fine fuels and woody fuels than other vegetation community types (e.g., Larrea tridentata [creosote bush] or Pinus monophylla/Juniperus osteosperma [pinyon/juniper communities]), resulting in increases in fine fuels at these sites more than sites in the Mojave Desert (southern one-third of the NNSS) or the Great Basin Desert (northern one-third of the NNSS).

Fine fuels produced in 2012 were almost completely lacking in most areas of the NNSS due to drought conditions. Overall, the hazards of residual fuels contributing to wildland fires are lower than average, but the dry condition of both fine and woody fuels make them more susceptible to ignition by lightning or other sources. Once ignited, high ambient temperatures and high winds contribute to the spread of fire in areas where the abundance of fuels is sufficient to carry the flames of the fire. Rapid response by NNSS Fire and Rescue after fires are ignited is a key factor in minimizing wildland fire spread and severity.

4.1.2.3         Invasive Plants

The three most commonly observed invasive annual plants to colonize burned areas on the NNSS are Schismus arabicus (Arabian schismus), found at low elevations; Bromus rubens (red brome), found at low to moderate elevations; and Bromus tectorum (cheatgrass), found at middle to high elevations

(Table 4-4). Most of the invasive annual plants failed to germinate during the spring of 2012. B. tectorum was present at only 17% of the sites. No living plants of B. rubens and S. arabicus were observed at any of the sampling sites. Precipitation history (Figure 4-2, shown previously) is also important in determining the percent presence of species across the NNSS. During periods of low precipitation, most annual species have low percent presence (i.e., the number of sites in which the plant was observed to be present and growing). Percent presence is generally greatest during periods of high precipitation, and appears to be a good indication of germination. Higher percent presence is also expected to occur when regional storms provide precipitation to a greater number of operational areas across the NNSS. However, the responses of some species, both invasive and native species, suggest that other variables, such as the timing of precipitation or temperatures required for germination, may also be contributing to plant response. For example, Mentzelia albicaulis (whitestem blazingstar) had only 8.1% presence in 2005 (the wettest year), but 51.9% presence in 2010, even though there was less precipitation during the same time period of that year, suggesting that temperature patterns may have been different in the 2 years.

Colonization by invasive species increases the likelihood of future wildland fires because they provide abundant fine fuels that are more closely spaced than native vegetation. C. ramosissima vegetation types appear to be the most vulnerable plant communities to fire, followed by P. monophylla/J. osteosperma/ Artemisia species (spp.) vegetation types. Wildland fires are costly to control and to mitigate once they occur. Revegetation of severely burned areas can be very slow without reseeding or transplanting with native species and other rehabilitation efforts. Untreated areas become much more vulnerable to future fires once invasive species, rather than native species, colonize a burned area.

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-6.    Site 99 on the west side of Yucca Flat in 2009–2012

(Photos by W. K. Ostler, April 30, 2009 [top left]; May 3, 2010 [top right]; April 26, 2011 [bottom left]; and April 10, 2012 [bottom right])

35

Ecological Monitoring and Compliance Program 2012 Report

Table 4-4. Precipitation history and percent presence of key plant species contributing to fine fuels at 106 surveyed sites

*30-year mean precipitation for the historical 17 rain gauges on the NNSS for the period of January–April 1981–2011 is 8.86 cm.

Germination of fine fuels produced by invasive, introduced annual species (especially B. tectorum) and other native annual species was second lowest since 2004. Only 2007 had lower germination and percent presence of annual and perennial herbaceous species. Germination during 2012 was lowest at lower elevations and greatest at higher elevations, reflecting the general trend of increasing precipitation with elevation. At higher elevations on the NNSS (e.g., Rainier and Pahute Mesas), much of the precipitation occurs as snow and is retained longer in the soil due to the lower temperatures. This lack of germination resulted from drought conditions experienced during 2012 (January through April).

4.2         West Nile Virus Surveillance

WNV is a potentially serious illness that spreads to humans and other animals through mosquito bites. It was first discovered in Uganda in 1937 and was not detected in North America until 1999. In southern Nevada, it was not detected until the spring of 2004. WNV surveillance on the NNSS continued in 2012 for the ninth consecutive year. WNV surveillance consists of setting mosquito traps baited with dry ice overnight at sites where standing water provides potential breeding sites for mosquitoes. As the dry ice sublimates, it produces carbon dioxide, which attracts mosquitoes. Seven sites were sampled during

15 surveys from May to September (Table 4-5). Mosquitoes collected during the surveys were taken to the Southern Nevada Health District (SNHD) for species identification and WNV testing. The six samples that contained mosquitoes were moldy, so they could not be identified or tested for WNV. Future samples will be dried before being placed into vials and taken to SNHD sooner, preferably within 2 weeks of collection. To date, WNV has not been detected conclusively on the NNSS, although two samples were suspect for WNV in 2005 and 2006 (Bechtel Nevada 2006, NSTec 2007). This suggests that the risk of NNSS workers being exposed to WNV on site is low.

Ecological Monitoring and Compliance Program 2012 Report

Table 4-5. Results of West Nile virus surveillance on the NNSS in 2012

LANL: Los Alamos National Laboratory SOC: Special Operations Center WNV: West Nile virus

4.3         Habitat Monitoring: Additional Reptile Sampling

The field mapping effort for reptile distributions continued with additional trapping at 20 sites and recording opportunistic observations at the NNSS during 2012. The technique involved setting

15 unbaited funnel traps at a site and trapping for 2 to 4 weeks. Additionally, species observations were recorded during site visits and opportunistically during other field activities. Spring trapping occurred during May at six sites in Mercury Valley. The effort (550 trap nights) targeted several species of snakes and one lizard historically known from this region but rarely captured. Species included the blind snake (Leptotyphlops humilis), leaf-nosed snake (Phyllorhynchus decurtatus), lyre snake (Trimorphodon biscutatus) and the Yucca Night lizard (Xantusia vigilis). None of these four species were captured in 2012. The last known Yucca Night lizard was captured in Mercury in 1992. Fourteen additional sites were trapped during July and August in Areas 12, 17, 18, 19, and 20 (970 trap nights). Several roadside sites were trapped, specifically for skinks, as well as areas away from roads (rocky areas and washes) where data gaps in reptile distribution were known.

Results identified 16 species at 27 new locations. Overall, 102 captures of nine species, and observations of 7 additional species were made in 2012. Notable captures included a Great Basin skink (Plestiodon skiltonianus) in Area 19 and a western red-tailed skink (Plestiodon gilberti rubricaudatus) in Area 18.

Both skinks were caught along paved roads in thick roadside patches of Ericameria nauseosa (Rubber rabbitbrush), which suggests this habitat type may be important for these species.

Ecological Monitoring and Compliance Program 2012 Report

Other species captured included the common side-blotched lizard (Uta stansburiana), the western banded gecko (Coleonyx variegatus), western whiptail (Cnemidophorus tigris), yellow backed spiny lizard (Sceloporus magister), Great Basin fence lizard (S. occidentalis), striped whipsnake (Masticophis taeniatus), and red racer (Masticophis flagellum). Observations were also made of the leopard lizard (Gambelia wislizenii), horned lizard (Phrynosoma platyrhinos), gopher snake (Pituophis catenifer), sidewinder rattlesnake (Crotalus cerastes), and speckled rattlesnake (Crotalus mitchellii). Both rattlesnake species were observed in Mercury. The rarely observed ring-necked snake (Diadophis punctatus) was opportunistically observed in Area 19 at a mountain lion (Puma concolor) trapping site. All data were entered into the reptile database, now containing over 6,000 records.

4.4         Natural Water Source Monitoring

4.4.1        Existing Water Sources

Water sources were monitored this year to characterize physical and biological parameters. Eleven water sources were visited at least once during 2012 to record wildlife use, the presence/absence of land disturbance, water flow rates when applicable, and surface area of standing water (Table 4-6).

Flow was estimated by collecting a known volume of water from a permanently installed pipe over a known time period. This method yields an approximate measurement and is generally an underestimate of true flow. At some sites, water collects, but there is no way to estimate flow, which was the situation at Gold Meadows Spring, Pahute Mesa Pond, and Yucca Playa Pond. Flow occurs as seepage through the local sediments or by overland flow into the pond collection area. Because monitoring of wetlands is qualitative, the objectives are to identify large or obvious changes over time. Smaller, subtle changes in flow are not readily detectable from this method. Sizes of the monitored water sources varied greatly from very small areas (<1 square meter [m²]) to moderately sized springs (180–600 m²) to large temporary playa pools (28,000 m²). Surface flow rates were typically low (<5 liters per minute) at most water sources where flow was measurable. Disturbance from horses was noted at three sites and some forms of natural change (dense spread of wetlands plants) occurred at another site (Table 4-6). Locations of natural water sources on the NNSS are shown in Figure 4-7.

Wildlife use data recorded during site visits are summarized in Table 4-7. Mule deer (Odocoileus hemionus), antelope (Antilocapra americana), and horses (Equus caballus) benefit significantly from the water sources. Overall in 2012, few birds including Chukar (Alectoris chukar) and mourning doves (Zenaida macroura) were observed throughout the NNSS (Table 4-7), indicative of a dry year. An extensive trapping effort for another project yielded only two individual dove captures. Observations of two short-eared owls (Asio flammeus) at Whiterock Spring were also documented during trapping.

The use of motion-activated cameras can be a useful tool for more detailed information than site visits alone (see Section 6.4.1, Motion-Activated Cameras). For example, two Steller’s Jays (Cyanocitta stelleri) were observed with a camera at Topopah Spring on September 13, 2012. This was the first record of this species since 1962. Previously, Hayward et al. (1963) had listed only eight historical sight records on the NNSS for August 22–23 and October 25. They stated that the Steller’s Jay appears to be uncommon in the Pinion Juniper and Oakbrush communities. It has also been reported more recently from southern Nevada in Ponderosa and Bristlecone pine forests (Greene et al. 1998). The lack of sightings over the last 20 years at NNSS, however, suggests it may not be very abundant here and likely may be an irregular migrant.

Monitoring for the presence of the Southeastern Pyrg snail (Pyrgulopis turbatrix) at Cane Spring continued in 2012. It was found in the outflow about 10 meters (m) from the cave pool near cattails. The species was present on September 26, 2012, and will be monitored to see if it spreads downstream to the

Ecological Monitoring and Compliance Program 2012 Report

watering trough located about 50 m away. It is considered a sensitive species in Nevada (Table 2-1) and occurs at only eight springs in southern Nevada.

Table 4-6. Hydrology and disturbance data recorded at natural water sources on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-7.   Natural water sources on the NNSS, including those monitored in 2012

Ecological Monitoring and Compliance Program 2012 Report

Table 4-7. Number of wildlife species observed or inferred (P = Present) at NNSS natural water sources in 2012

4.4.2        New Water Sources

Eight new water sources were discovered during 2011–12 on the NNSS during mountain lion monitoring (Table 4-8, Figure 4-7). Seven of these are rock tanks and one is a seep. Tanks collect water from overland flow after precipitation events (e.g., runoff from rain or melting snow). Depending on the depth and size of the tank, rock type, surrounding topography, and timing of precipitation, these tanks may hold water for a few weeks to several months. These are important, albeit ephemeral, sources of water for

Ecological Monitoring and Compliance Program 2012 Report

several species of wildlife (see Section 6.4.1, Motion-Activated Cameras, Table 6-4). Hall’s Seep (Figure 4-8) was found in August while searching for mountain lion kills. It was revisited in November

and still had water, suggesting this is a permanent water source. Previous human use was evident with the presence of some old metal pipes used to direct flow down slope and other artifacts.

Figure 4-8.   Hall’s Seep, a newly discovered small seep in Area 29, Topopah Valley

(Photo by D. B. Hall, August 1, 2012)

Table 4-8. New water sources detected during mountain lion monitoring in 2011–12 on the NNSS Name                    Date Found     Surface Area (m²)     Elevation (m)    Major Vegetation

Ecological Monitoring and Compliance Program 2012 Report

4.5         Constructed Water Source Monitoring

4.5.1        Plastic Sump Monitoring

Site biologists conducted quarterly monitoring of selected constructed water sources. These sources, located throughout the NNSS (Figure 4-9), include plastic-lined sumps at 23 sites. Several ponds or sumps may be located next to each other at the same project site. Many animals rely on these

human-made structures as sources of water. However, wildlife and migratory birds have drowned under certain conditions in steep-sided plastic-lined sumps from entrapment. Therefore, ponds are monitored to assess their use and impacts to wildlife. Over time, mitigation measures, such as the emplacement of sediment ramps, have been recommended to prevent entrapment or significant harm to wildlife.

During March, July, October, and December 2012, biologists visited 44 constructed water sources (Table 4-9). At each site, the presence or absence of standing water and the presence of animals or their sign around the water source were recorded. Sediment ramps or plastic ladders, which allow animals to escape if they fall in, have been installed at many plastic-lined sumps. The presence, absence, and condition of these structures were also noted. All dead animals in or adjacent to a human-made water source were recorded (Table 4-9). Monitoring frequency was low in 2012 because many of the older sumps appear to have very low risk of entrapping animals. Older liners become less slippery over time due to weathering, thus allowing animals to escape. During 2012, no dead animals were detected in sumps on the NNSS. Most sumps were dry from spring to midsummer. Substantial rainfall events occurred in July, August, and September, and water accumulated in many sumps during this time period. Most sumps accumulated additional water from the first snows in mid- to late December. Wildlife use documented during site visits was limited to common species of passerine birds, ducks, and shorebirds.

Sediment ramps are still missing in many sumps on the NNSS. Where they have been installed, they have been very effective in allowing animals to exit sumps under conditions of deep water. Sediment ramps that are used by wildlife (typically coyotes and deer) have fresh tracks. In the future, sediment ramps should be emplaced in new sumps when they are constructed, especially if water is deep.

4.5.2        Mitigating Water Loss for Wildlife

Water conservation measures were implemented on the NNSS during 2012 at four sites: Area 6 Construction Yard (Area 6, LANL Pond), Well C1 Pond, Well 5B Pond, and J11 Pond. In order to conserve millions of gallons of water being lost to drainage and evaporation, pumping water to fill these ponds was stopped. Wildlife observation data gathered over several decades documented more than

100 species of wildlife using these artificial water sources. These included carnivores, ungulates, rabbits, bats, and dozens of species of waterfowl, passerines, and other birds.

Drying these ponds up would result in the loss of valuable wildlife habitat, so a decision was made to install water troughs to help mitigate the loss of the well ponds. The water troughs were not meant to replace the well ponds as wildlife habitat, but were meant to provide at a minimum some supplemental water in areas with very limited perennial water sources and at sites where animals had become accustomed to finding water. Water troughs were installed adjacent to the Area 6 Construction Yard and Well C1 Pond to mitigate the loss of these ponds, at Well 5A (Well 5C) to mitigate the loss of the

Well 5B Pond, and at Cane Spring and Topopah Spring to mitigate the loss of the J11 Pond (Figure 4-9).

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-9.   Constructed water sources monitored for wildlife use and mortality and locations of newly installed water troughs on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Table 4-9. Results of monitoring plastic-lined sumps for wildlife mortality on the NNSS for 2012

Motion-activated cameras were set up at each trough in September and November to document wildlife use and were also added to the network of cameras used for monitoring mountain lions. Wildlife use documented by cameras already set up at Cane Spring and Topopah Spring will be used to compare use at the spring to use at the water troughs. Detailed results of wildlife use at the troughs are found in

Section 6.4.1, Table 6-4. The trough at Well 5C is being used regularly by wild burros (Equus asinus) (Figure 4-10) and pronghorn antelope (Figure 4-11). The trough near Topopah Spring has been used by mule deer (Figure 4-12) and a red-tailed hawk (Buteo jamaicensis) (Figure 4-13). There was still water present in all the sumps at the end of 2012. As these sumps completely dry up in the future, it is anticipated that more wildlife use will be recorded at the troughs.

4.6         Coordination with Scientists and Ecosystem Management Agencies

Site biologists interfaced with other scientists and ecosystem management agencies in 2012 for the following activities:

• Participated in a meeting of the Mojave Desert Initiative designed to address research needs in the areas of wildfires and reclamation of Mojave Desert lands.
• Assisted field crews from the Rocky Mountain Research Station (Ogden, Utah) in conducting forest inventory and analysis for the U.S. Forest Service.

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-10. Wild burro at water trough near Well 5C, Area 5

(Photo taken September 12, 2012, by motion-activated camera)

Figure 4-11. Pronghorn antelope drinking from water trough at Well 5C, Area 5

(Photo taken September 25, 2012, by motion-activated camera)

Ecological Monitoring and Compliance Program 2012 Report

Figure 4-12. Mule deer drinking from water trough near Topopah Spring

(Photo taken November 24, 2012, by motion-activated camera)

Figure 4-13. Red-tailed hawk perched on water trough near Topopah Spring

(Photo taken November 21, 2012, by motion-activated camera)

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Ecological Monitoring and Compliance Program 2012 Report

5.0            SENSITIVE PLANT MONITORING

The list of sensitive plants on the NNSS is reviewed annually to ensure that the appropriate species are included in the NNSS Sensitive Plant Monitoring Program. The review takes into consideration information gathered on sensitive plants during the current year by NSTec botanists as well as input from regional botanists with expertise or knowledge with particular species. As part of the Adaptive Management Plan for Sensitive Plant Species (Bechtel Nevada 2001), the status of each plant is monitored periodically to ensure NNSS activities are not impacting the species. Field surveys are also routinely conducted to verify previously reported locations, to better define population boundaries, and to identify potential habitat for sensitive plant species known to occur on or adjacent to the NNSS. Information gathered during the year on sensitive plants is disseminated to state and federal agencies and other interested entities.

5.1             List of Sensitive Plant Species on the NNSS

The sensitive plants included in the NNSS Sensitive Plant Monitoring Program are included on the list of At-Risk species published by the NNHP and the status list prepared by the Nevada Native Plant Society (NNPS). Currently there are 17 vascular plants and 1 non-vascular plant considered sensitive and warrant inclusion in the NNSS Sensitive Plant Monitoring Program. There was a pending taxonomic issue with one species on the list that was resolved. A major accomplishment this year was a re-evaluation of the ranking of sensitive plants on the NNSS. The status of each sensitive plant was evaluated based on its overall distribution, abundance, and rarity.

Taxonomy – In 2011 (Hansen et al. 2012), the occurrence of Galium hilendiae subspecies (ssp.) kingstonense (Kingston Mountains bedstraw) on the NNSS was undetermined. In 2011, plant specimens were collected at a reported site of G. hilendiae ssp. kingstonense in the Kingston Mountains. The specimens appeared to be different from the Galium found on the NNSS, which also had been reported as

G. hilendiae ssp. kingstonense. In an attempt to verify the taxonomy of the species of Galium found on the NNSS, specimens collected from the NNSS and from the Kingston Mountains were sent to the Rancho Santa Ana Botanic Garden, in Claremont, California, for positive identification.

Botanists at the Rancho Santa Ana Botanic Garden confirmed that the specimens collected on the NNSS were indeed the ssp. kingstonense, whereas the one collected in the Kingston Mountains was

G. matthewsii. The personal communication from Duncan S. Bell, Field Botanist at the Rancho Santa Ana Botanic Garden in Claremont, California, reads as follows:

Your Galium collections from the Kingston mountains were Galium matthewsii and your Galium collection from Nevada do appear to be Galium hilendiae ssp. kingstonense. This is a great find and a range extension as this plant was endemic to the Kingston range. . . .

I’m sure other botanists will be stopping by our herbarium soon to see them as I believe these are the first collections to come out of Nevada. As far as I know these are the first physical records from Nevada and a new addition to the flora of Nevada. I wouldn’t be surprised if they are also found in some of the other ranges in the area that haven’t been explored.

Based on these findings the Galium found on the NNSS has been confirmed to be that of the rare subspecies G. hilendiae ssp. kingstonense. This plant was previously only known from the type locality in the Kingston Mountains, but now is known to occur on the NNSS (see Section 5.4.2 for additional information).

Ecological Monitoring and Compliance Program 2012 Report

Plant Ranking – Over the years there have been various classifications or rankings of the sensitive plants found on the NNSS. The first lists developed close to 40 years ago classified plants as threatened, endangered, or “watched.” With the ESA came official classification/designation as listed endangered, listed threatened, proposed endangered, proposed threatened, or a candidate for listing as either threatened or endangered. Internal ranking of sensitive plants on the NNSS typically followed the aforementioned designations. Currently, no sensitive plants known to occur on the NNSS have been listed under the ESA.

When the Adaptive Management Plan for Sensitive Plant Species (Bechtel Nevada 2001) was prepared, sensitive plants on the NNSS plants were categorized as active, inactive, or evaluate. Later in 2008, sensitive plants on the NNSS were grouped into two categories: those monitored every 5 years and those monitored every 10 years (Hansen et al. 2009). The NNPS’s classification was adopted in 2010 in which plants were either listed as threatened or on a watch list.

Over the last decade, monitoring under the Adaptive Management Plan’s guidelines has focused on delineating the extent of the distribution of sensitive plants on the NNSS and verifying previously reported locations. Currently, sufficient information has been gathered to facilitate a site-specific ranking for the sensitive plants that occur on the NNSS. Such a ranking was completed in 2012. The ranking followed a ranking system used by the Utah Native Plant Society (Fertig 2009), which was modified to be more representative of the sensitive plants found on the NNSS. The ranking is based on several criteria, including the number of populations throughout its range, within Nevada, and on the NNSS; global and local abundance; habitat specificity; intrinsic rarity; threats; and population trends (Table 5-1). The criteria used are based on the biology and ecology of the species rather than from a management or administrative perspective.

A numerical value was assigned to each ranking criteria. The values were summed for each sensitive plant and assigned to one of four rankings or priorities. Sensitive plant species with a total numerical rating of 11 or greater were assigned as a High priority species; those scoring between 8 and 10 were assigned to a Moderate ranking; those with a rating of 4 to 7 were assigned as Watch; and those with a rating of less than 4 were considered a Marginal species (Table 5-2).

Six of the 18 sensitive plants that occur on the NNSS are ranked in the High priority category. These six species are known from just a few populations and in several cases are only known from the NNSS or within the immediate vicinity of the NNSS. Ivesia arizonica variety (var.) saxosa (Rock purpusia), ranked the highest of the ten species, is known from two sites on the NNSS and from the North and South Pahroc mountains in Lincoln County, Nevada, the type locality. There are fewer than 6,000 individuals on the NNSS, and the Pahroc Mountains population, although not thoroughly surveyed, appears to be about twice the size of the NNSS population. The other five High priority species are known from less than three locations on the NNSS and an equally small number of locations off the NNSS.

Seven species are ranked Moderate. The two highest rated species within this group are Eriogonum concinnum (Darin buckwheat) and Camissonia megalantha (Cane Spring suncup), both originally named from collections on the NNSS and less common than the other species in this group. Other species in this group include Arctomecon merriamii (White bearpoppy) and two annual plants, Phacelia filiae (Clarke phacelia) and P. beatleyae (Beatley scorpionflower). These species are locally abundant when growing conditions are favorable, and almost completely absent in dry years. Populations of A. merriamii have been impacted by development in and around the Las Vegas metropolitan area. Populations on the NNSS are generally in isolated areas and unaffected by NNSS operational activities, but some populations in Mercury have been impacted.

Ecological Monitoring and Compliance Program 2012 Report

Table 5-1. Criteria used in ranking sensitive plants known to occur on the NNSS

The Watch list includes four plant species that are common on the NNSS as well as at other locations in southern Nevada. Astragalus oophorus var. clokeyanus (Clokey eggvetch) was originally considered quite rare with a few scattered occurrences reported in the Spring Mountains to the south of the NNSS and in the Belted Range north of the NNSS. Currently, over 1,500 plants have been located at nine different locations on the NNSS. There is the possibility of encountering even more populations because much of the potential habitat for this species is in remote areas and has not been surveyed. Hulsea vestita ssp. inyoensis (Inyo hulsea) and Penstemon pahutensis (Pahute Mesa beardtongue) do not occur in large numbers on the NNSS but are found over most of the northern mesas of the NNSS. Both species are known to occur in nearby mountain ranges as well. In recent years, the abundance of Eriogonum heermannii var. clokeyi (Clokey buckwheat) has been well documented on the NNSS. Over

Ecological Monitoring and Compliance Program 2012 Report

5,000 individuals have been located along Mercury Ridge in the Spotted Range, which is the only known location of the species on the NNSS. Major populations of this species are found in the Spring Mountains and Sheep Mountains to the south and east of the NNSS.

Phacelia mustelina (Weasel phacelia) was the single species ranked as Marginal. In recent years, this species has been found at numerous locations on the NNSS. It does not occur in large numbers but does occur over most of the NNSS as well as at many locations off the NNSS.

Table 5-2. Ranking of sensitive plants known to occur on the NNSS

Monitoring and field surveys in future years will consider these new rankings when scheduling and conducting sensitive plant monitoring activities. The database set up for recording locations of all sensitive plants on the NNSS will continue to be updated with all sensitive plant species on the NNSS (see Table 2-1). Rankings may be re-applied over time not only to those currently being included in the NNSS Sensitive Plant Monitoring Program but other plant species that may warrant closer attention.

Ecological Monitoring and Compliance Program 2012 Report

5.2             Program Awareness

The annual Rare Plant Workshop, sponsored by NNHP and the NNPS, was held October 1–2, 2012, at the Springs Preserve in Las Vegas, Nevada. There were no actions or recommendations from the participants of the workshop that affected the sensitive plants that are listed for the NNSS.

As part of the state-wide effort to disseminate information throughout the botanical community, NSTec prepared site-specific data for all 18 sensitive plants and provided it to the NNHP for incorporation into their databases. The data included approximately 20,500 locations of sensitive plants on the NNSS or within the immediate vicinity of the NNSS. For some species, such as Camissonia megalantha

(Cane Spring suncup) and Astragalus funereus (Black woollypod), as little as 10 locations were provided, whereas data for other species included thousands of locations.

5.3             Monitoring

Monitoring sensitive plant populations on the NNSS was scheduled for C. megalantha and for A. funereus and E. concinnum, which had been re-scheduled from 2011. Growing conditions were less than optimal again this year, and no monitoring was completed for these species. Monitoring will be conducted when growing conditions are favorable.

A map was prepared this year delineating the geographical regions on the NNSS (Figure 5-1). The names of the geographic regions, as well as features within each region, are based on information from

U.S. Geological Survey (USGS) topographic maps. Previous descriptions of the locations for many sensitive plants were based on man-made facilities that no longer exist or are not associated with a particular area on the NNSS. The description of the location of sensitive plant populations on the NNSS have been or will be renamed to reflect geographical regions and features within each region.

5.4             Field Surveys and Opportunistic Sightings

The lack of precipitation on the NNSS resulted in less than optimal growing conditions again this year, and field surveys were limited. Surveys were conducted for Ivesia arizonica var. saxosa on Pahute Mesa and A. merriamii along Mercury Ridge. In spite of the poor growing conditions, this year both were locally abundant and field surveys provided valuable information on their distribution and abundance.

Field activities associated with other environmental monitoring tasks occur over much of the NNSS, and the opportunity for opportunistic sightings is always present. Such was the case this year. Frasera pahutensis (Pahute green gentian) was found at several locations on Pahute Mesa, primarily within current known population boundaries. The most significant opportunistic sighting was the location of two populations of G. hilendiae ssp. kingstonense.

Ecological Monitoring and Compliance Program 2012 Report

Figure 5-1.   Geographical regions on the NNSS

5.4.1        Ivesia arizonica var. saxosa, Rock Purpusia

Field surveys for I. arizonica var. saxosa prior to 2012 resulted in multiple disjointed populations. This year surveys focused on areas between those populations. Originally 100–150 plants were reported in the Columbine Canyon area (Anderson and Ostler 2009) on Pahute Mesa (Figure 5-2, blue outline). In 2011, 400-plus individuals were found in similar habitat south of Columbine Canyon (Figure 5-2, yellow). This year surveys were conducted from the area around Columbine Canyon south through several canyons with potential I. arizonica var. saxosa habitat. The surveys resulted in the documentation of over

5,000 new individuals in this area (Figure 5-2, brown). The number of individuals of I. arizonica var.

saxosa on the NNSS is estimated to be in excess of 5,500, covering approximately 28 ha.

Ecological Monitoring and Compliance Program 2012 Report

The only other location of I. arizonica var. saxosa on the NNSS is in Pah canyon, where only a few individual plants have been reported. A reconnaissance survey at the type locality for this species in the Pahroc Mountains in Lincoln County confirmed that the variety of I. arizonica found on the NNSS is indeed the variety saxosa. Numerous other areas with similar habitat have been surveyed on the NNSS, but to date I. arizonica var. saxosa has not been found, only I. arizonica ssp. arizonica.

Figure 5-2.   Comparison of original reported location (outlined in blue) of I. arizonica var. saxosa and locations found between 2007 and 2011 (yellow) to current known distribution (brown)

Ecological Monitoring and Compliance Program 2012 Report

5.4.2        Arctomecon merriamii

There have been no surveys on the NNSS for A. merriamii conducted since the early 1990s. A. merriamii was unexpectedly abundant this year in spite of the poor growing conditions, and, although not planned, field surveys were scheduled and conducted. Several new locations were found along Mercury Ridge and several more at lower elevations around the Mercury townsite (Figure 5-3). As with recent surveys for other species, the boundaries of the populations, previously plotted on field topographic maps, were better-defined using GPS devices and mapping software.

Comprehensive surveys for A. merriamii conducted in the early 1990s (Blomquist et al. 1995) reported 13 locations of the species and an estimate of about 3,000 individuals on the NNSS. Surveys conducted

this year from mid-April to mid-May found 15 new locations (Figure 5-4) and redefined the boundaries of several of the populations identified in 1995 (Anderson and Ostler 2009). Based on this year’s surveys, the number of individuals of A. merriamii on the NNSS is estimated to be in excess of 4,500 and covering approximately 53 ha.

Figure 5-3.   Original reported locations of A. merriamii around the Mercury townsite and along Mercury Ridge in the Spotted Range (red) compared to locations added in 2012 (yellow)

Ecological Monitoring and Compliance Program 2012 Report

Figure 5-4.   A. merriamii in full flower along the side hills of Mercury Ridge in the Spotted Range

(Photo by D. Anderson, April 18, 2012)

5.4.3        Galium hilendiae ssp. kingstonense, Kingston Mountain bedstraw

Even though no field surveys were planned for G. hilendiae ssp. kingstonense this year, two significant populations were found during other field activities. One population was found in the southeastern region of Gold Meadows and another in Oak Canyon, just north of Oak Spring Butte (Figure 5-5). Both populations were located late in the season, yet plants were in flower and fruit.

The population found at Gold Meadows is the largest found so far on the NNSS. More than

1,300 individuals were located in the understory of pinyon, interspersed within oak thickets or at the base of large rocks or boulders. The area is an open woodland on a steep north facing slope with most plants found mid-slope to upper slope (Figure 5-6). This population was encountered in mid-September, but even at this late date, most plants were in flower due to monsoon rains that came in late July and August.

A second population of G. hilendiae ssp. kingstonense was found on a steep north facing slope in Oak Canyon, which is located a few hundred meters north of the NNSS boundary on the north side of Oak Spring Butte. This population was found in October and plants had set seed. Approximately

300 plants were located within the estimated 8,000 m² that were surveyed. Potential habitat at this site would be close to 150,000 m². Slopes were steeper than at the Gold Meadows site, but like the population at Gold Meadows, plants were found in the understory of pinyon, in oak thickets, or at the base of large rocks or boulders.

Ecological Monitoring and Compliance Program 2012 Report

The two populations of G. hilendiae ssp. kingstonense located this year have the highest density of plants encountered for this species so far. About 300 plants were reported at the site just west of Oak Spring Butte. This site covered about 4 ha, suggesting a plant density at this site of about 75 plants/ha. East of Oak Spring Butte at Tub Spring, only 50 plants were reported over an area less than a hectare, or a plant density of about 50 plants/ha. The density of plants at the Tongue Wash location was approximately

100 plants over 2 ha, or an estimated plant density of 50 plants/ha. The estimated plant density at Gold Meadows was about 325 plants/ha (1,300 plants over 4 ha). The density of G. hilendiae ssp. kingstonense at this site is probably higher than reported because a 100% survey was hindered by steep, rugged terrain. It was equally difficult to determine a density for the Oak Canyon population. Access was limited at this site and only a small portion of the site was surveyed, leaving some uncertainty as to whether it occurs over the entire slope. The portion of the slope surveyed was estimated to cover 0.8 ha. Within that area 300 plants were found, suggesting a density of around 375 plants/ha.

Figure 5-5.   Known distribution of G. hilendiae ssp. kingstonense on NNSS: original locations highlighted in red, new populations recently located highlighted in yellow

Ecological Monitoring and Compliance Program 2012 Report

Figure 5-6.   Typical habitat for G. hilendiae ssp. kingstonense on the NNSS

(Photo by D. Anderson, September 19, 2012)

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6.0            SENSITIVE AND PROTECTED/REGULATED ANIMAL MONITORING

The NNHP Animal and Plant At-Risk Tracking List; NAC 503, “Hunting, Fishing and Trapping; Miscellaneous Protective Measures”; and other sources were reviewed to determine if any changes had been made to the status of animal species known to occur on the NNSS. Three changes to the status of NNSS species were noted. A change was made for the western red-tailed skink from “Evaluate” status to “Inactive” status because enough information was obtained from the distribution study to warrant this change, and desert tortoise and wild burro were changed to “Active” status. The complete list with current designations is found in the Sensitive and Protected/Regulated Animal Species List (Table 2-1, shown previously).

Surveys of sensitive and protected/regulated animals during 2012 focused on (a) bats, (b) wild horses,

(c) mule deer, and (d) mountain lions. Information about other noteworthy wildlife observations, bird mortalities, and a summary of nuisance animals and their control on the NNSS are also presented.

6.1             Bat Surveys

In 2012, bat monitoring focused on passive acoustic monitoring of bat activity at Camp 17 Pond, and removing bats from buildings and documenting bat roosts.

6.1.1        Passive Acoustic Monitoring System at Camp 17 Pond

To learn more about long-term bat activity through different seasons and years, a passive acoustic monitoring system (Anabat II) was installed at Camp 17 Pond on September 22, 2003. Hundreds of thousands of electronic files containing bat calls have been recorded and are being analyzed by O’Farrell Biological Consulting as funding becomes available. Bat vocalizations and climatic data

(e.g., temperature, humidity, wind, barometric pressure) were recorded again in 2012, but no analysis was performed due to a limited budget.

6.1.2        Bats at Buildings

During 2012, site biologists responded to six nuisance bat calls. All six were at buildings around Mercury (one at the Mercury cafeteria, two at Building 143, one at Building 751, one at Building 117, and one at Building 1001). Three of the bats were California myotis (Myotis californicus) (two adult females and one adult male), one was an adult female pallid bat (Antrozous pallidus), and two were not identified to species. One bat was found dead and the other bats were removed and released or flew off on their own. Roost site locations were entered in the Ecological Geographic Information System faunal database.

6.2        Wild Horse Surveys

Horse monitoring provides information on the abundance, recruitment (i.e., survival of horses to reproductive age), and distribution of the horse population on the NNSS. Annual monitoring of individual horses at NNSS began in 1989 and has continued through 2012. In 2012, NSTec biologists determined horse abundance and recorded horse sign (e.g., droppings and hoof prints) along roads. Some of the natural and human-made water sources were visited in the summer of 2012 to assess their influence on horse distribution and movements and to document the impact horses are having on NNSS water sources. Important information on horse abundance and recruitment from 1990 to 1998 is found in Greger and Romney (1999).

Ecological Monitoring and Compliance Program 2012 Report

6.2.1        Abundance

In 2012, counts of horses were made during 26 non-consecutive days between May and November. A standard road course was driven to locate and identify horses. Motion-activated cameras at Camp 17 Pond, Gold Meadows Spring, and Captain Jack Spring were also used to photograph horses (see Section 6.4.1, Motion-Activated Cameras). Individuals were identified by their unique physical markings (facial blazes) and classified as foal, yearling, or older when possible. Excluding foals, 35 horses were counted in 2012. This is a close approximation to the actual number of horses that are present. About seven horse bands were detected, which were composed of stallions, subordinate males, females, and their offspring. The NNSS horse population in 2012 is stable at about 35 individuals. Survival of yearlings and foals was low in 2012, as in previous years (Figure 6-1).

Figure 6-1.   Trends in the age structure of the NNSS horse population from 2003 to 2012

Observations and photos taken indicate that at least six foals were born in 2012 (Figure 6-1), and as in other years most disappeared during the summer. Greger and Romney (1999) found that over 60 healthy foals were lost over a 5-year period at the NNSS, and hypothesized that mountain lion predation was the primary cause. Foal losses are a significant factor in controlling the size of the herd of horses on the NNSS, and the horse population has declined in size by about 40% since 1989 when horse population monitoring began. Four foals were killed on the NNSS by a radio-collared mature male mountain lion (NNSS4) between July 17 and December 6, 2012. This provides strong empirical evidence that supports the hypothesis of Greger and Romney (1999) that mountain lion predation on horse foals is controlling the horse population on the NNSS. Kills were located within 1–3 kilometers (km) of Camp 17 Pond and Gold Meadows Spring, critical water sources for horses (Figure 6-2).

6.2.2        Annual Range Survey

During 2012, selected roads were driven within the NNSS, and all band sightings and fresh sign (estimated to be <1 year old) were recorded (Figure 6-2). Walking surveys were also done occasionally away from roads to document horse activity. Horse sign data collected during the road and walking surveys indicate that the horse range on the NNSS during 2012 included Gold Meadows, Eleana Range, the southwest foothills of the Eleana Range, the Echo Peak region of Pahute Mesa, and Wildhorse Seeps

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-2.    Feral horse sightings, horse sign, and mountain lion kills observed on the NNSS during 2012

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in Area 30 (Figure 6-2). Overall, the estimated annual horse range in 2012 (206 square kilometers [km²]) is about 10% smaller in size than 2011. The horse range boundary line was approximated using the locations of horses and fresh horse sign documented for 2012. Overall, horse use has declined in the hills surrounding the Eleana Range and the Captain Jack Spring area and southward. Annual monitoring of horse use at springs indicates that the range is now smaller on the NNSS. This fact is consistent with declining population size of this herd. The herd, once numbered up to about 65 horses, has declined by nearly half in 10–12 years. Horses were commonly seen on Yucca Flat (Areas 8, 9, 12, and 2) during previous times and now seem restricted to the western edge of the Eleana Range and north into Areas 30, 17, and 18. These areas are characterized by rather rugged topography and rolling hills with pinion- juniper and sagebrush and are limited to a radius of approximately 8–11 km from any permanent water source. Horse activity was heaviest along roads from Camp 17 Pond in all directions as shown by the concentration of points in Figure 6-2. The preferred horse range seems to be above 1,524 m (5,000 ft) elevation, especially during the summer months.

6.2.3        Horse Use of Water Sources

Camp 17 Pond and Gold Meadows Spring were two primary water sources used in 2012 by horses, as in previous years. Camp 17 Pond is permanent, and horse use generally begins in March and extends through November. Gold Meadows Spring is temporary, and usage is from about April until it dries out in the fall. Wildhorse seeps in Area 30 are also temporary water sources in slick rock areas (Figure 6-2) containing several water tanks on the southern edge of the horse range. They are used mostly in fall and winter. Captain Jack Spring was not used by horses during 2011 or in 2012. None of the plastic-lined sumps within or near the horse range were used by horses this year.

6.3         Mule Deer

Initial studies of mule deer at the NNSS were conducted by Giles and Cooper (1985) from 1977 to 1982 when they performed mark and recapture studies on about 100 marked deer. They estimated the population to be about 1,500–2,000 deer. Spotlighting surveys for deer on the NNSS were conducted in 1989–1994, 1999–2000, and 2006 to the present. The monitoring effort has emphasized estimating relative abundance and density.

6.3.1          Mule Deer Abundance

Mule deer abundance on the NNSS was measured by driving two standardized (74 km total length) road courses (Figure 6-3) to count and identify mule deer. One route was centered around Rainier Mesa and the second was centered around Pahute Mesa, following advice that there are two main deer herd components in these regions on the NNSS (Giles and Cooper 1985).

Locations of mule deer and selected predators were recorded with a GPS from the road centerline. Perpendicular distance from the road to each deer group was measured with a laser range finder. Locations of deer groups were displayed using GIS methodology (see Hansen et al. 2009).

During nine surveys conducted in 2012, total observations were made of only 179 deer, which equates to an average of 20 deer per night. The deer counts in 2012 were 50% lower than counts in 2011 and about 40% lower than the long-term average of 32 deer per night. Possible reasons for the decline include drought conditions, predation, or a combination of factors. There appears to be no distinctive long-term trend in deer numbers on the NNSS (Figure 6-4).

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Figure 6-3.    Road routes and sub-routes of two NNSS regions driven to count deer

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Figure 6-4.   Trends in total deer count per night from 1989 to 2012 on the NNSS (surveys were not conducted during 1995–1998 or 2001–2005)

Overall, from 2006 to 2012, there were significantly higher deer numbers detected per distance (Analysis of variance, F = 16.8, d.f. = 129, P = 0.00001) on the Rainier Mesa route than on the Pahute Mesa route (Figure 6-5). In addition, there was a significant increase in the number of deer on the Rainier Mesa section during 2006 to 2012 compared to the number of deer on the same section during 1989–1994, while numbers of deer on the Pahute Mesa route were similar between the same time periods. Reasons for the increased number of deer on the Rainier Mesa route are not known but may be related to decreased human activity or number and distribution of water sources in these areas.

6.3.2        Mule Deer Density

Densities of deer were calculated using the software program DISTANCE (Thomas et al. 2006) on two routes and several sub-routes (Figure 6-3). Stratification of the data was based mostly on differences in topography and elevation. A statistic called Akaike’s Information Criterion (AIC) is used to assess model fit. The procedure involves running several models simultaneously on the data set and choosing the model with the lowest AIC to calculate density. A series of tests such as likelihood ratios and goodness of fit tests are also used along with visual inspection to evaluate the overall fit. In DISTANCE, the model fit closest to the centerline is the most important area to be concerned about, and agreement here allows the best fit (i.e., lowest AIC value).

Ecological Monitoring and Compliance Program 2012 Report

The effective strip width (ESW) or (half width) is an important parameter in DISTANCE that is used to calculate density (D), with n = the number of animals counted (mean cluster size × cluster density) in area (A) sampled, A = 2 × ESW × L, with L as the transect length.

Figure 6-5.    Mean number of mule deer per 10 km per night, counted on two routes (N = number of survey nights; for 2012, N = 9)

During the nine surveys conducted in September and October 2012, 96 observations (deer groups) were detected. Group size varied from one to five animals, and mean cluster size was 1.5 and 1.4 deer for the Rainier Mesa and Pahute Mesa routes, respectively. Density estimates for the Pahute Mesa route and Rainier Mesa route and sub-routes were low on the NNSS, averaging about 1 deer per km² (Table 6-1). There were few significant differences in density between any route or sub-route (most 95% confidence intervals overlapped). As in previous years, the two areas with the highest deer density were Gold Meadows and Echo Peak (1.8 and 2.1 deer per km², respectively). Egg Point Burn also had a density of

1.8 deer per km². Some areas with very low sample size had very high coefficients of variation. Roads and trails have numerous blind areas near the centerline; when surveys are conducted in these areas, animals will generally be undercounted (Buckland et al. 2001), resulting in an underestimate of density. Inspection of DISTANCE deer detection curves in 2012 as in previous years suggests that some undercounting of deer near the centerline is likely. The problem encountered in 2012 was that counts were very low, making it difficult to fulfill most assumptions of distance modeling. Some sub-routes therefore had counts that were too low to calculate density (Table 6-1), namely Holmes Road/Stockade Wash and Tongue Wash. Not unexpected, relative mule deer density trends across years (2007–2012) have been very similar to counts per night with no definitive trend.

Ecological Monitoring and Compliance Program 2012 Report

Table 6-1. Deer density estimates, confidence intervals, and other parameters for two routes and sub-routes of the NNSS for 2012 using Program DISTANCE software

Survey Routes/Sub-routes^a

s     D , n/Km

6.3.3        Sex and Fawn/Doe Ratios

The sex of some deer could not be determined during surveys. The percentage of deer whose sex could not be determined ranged from 15% in 2009 to 21% in 2007 and 2012; therefore, calculated sex ratios are likely to have some error. Sex ratios (number of males/female) have fluctuated from 0.89 in 2010 to 2.18 in 2007 (Table 6-2) but are often near 1, as was the case in 2012 with a ratio of 0.97. Generally, deer populations in hunted areas in the western U.S. have fewer males compared to females in the population than is measured on the NNSS. Giles and Cooper (1985) attributed the higher number of males to a lack of hunting on the NNSS.

The number of fawns detected in 2012 was 19, which was low, as in previous years, but total deer counts were also low in 2012. Giles and Cooper (1985) conducted fawn/doe surveys from July to October (1977–1981) and determined fawn/doe ratios ranged from 0.34 to 0.73. These values have always been much higher than those determined in more recent years on the NNSS (0.0 to 0.32; Table 6-2).

Table 6-2.  Mule deer sex ratios, fawns, and fawn to doe ratios across years on the NNSS

Year       Male     Female     Unclassified

Male/Female

Fawns     Fawns/Doe

6.3.4       

Mule Deer Habitat Use

Deer habitat use was calculated again in 2012 similarly as in previous years, using associations and alliances described by Ostler et al. (2000). Details of the field methodology were reported in 2011

Ecological Monitoring and Compliance Program 2012 Report

(Hansen et al. 2012). Deer habitat use indices (Table 6-3) were calculated by the quotient of percentage of deer habitat use and the percentage of available vegetative habitat (Stapp and Guttilla 2002). Confidence intervals of selection coefficients were calculated after Krebs (1999) to examine statistical differences (Table 6-3).

Two woodland associations, Pinus monophylla/Artemisa tridentata Woodland (PIMO/ARTR) and

Pinus monophylla/Artemisa nova Woodland (PIMO/ARNO) comprise about 42% of the habitat where deer observations were made (Table 6-3). The Artemisia spp. Shrubland Alliance (Artemisia spp.) (29%) and the Miscellaneous/disturbed habitats (20%) were also substantial components of the habitat.

However, Coleogyne ramosissima–Ephedra nevadensis Shrubland (CORA-EPNE) and the Egg Point Burn comprised minor components of the habitats on the deer routes (Table 6-3). The miscellaneous/ disturbed category is composed of several elements, both minor vegetation types and land previously disturbed by NNSA/NFO activities. Minor vegetation types included Cercocarpus spp. and the Chrysothamnus-Ericameria Shrubland Alliance.

The most heavily used habitat for deer was the Artemisia spp. Alliance, as in most previous years. In 2012 due to low counts, the standard errors of the habitat use index (W_i) were all higher, resulting in no positive selectivity values (Table 6-3). Only the CORA-EPNE Shrubland and the Miscellaneous-disturbed habitats appeared to be avoided (W_i <1.0) relative to availability in 2012.

Numbers of deer observed in most years are typically highest along the Artemisia spp. Alliance and the PIMO/ARTR Woodland boundary on the NNSS (Figure 6-6), with mostly higher selection values for the Artemisia spp. Alliance habitat. This is an important habitat ecotone for mule deer because they thrive in “edge” habitat (i.e., wooded areas interspersed with open sagebrush meadows). Explaining the difference in deer use among habitats is not possible at this time. Differential use may be due to detectability issues, such as good or poor visibility for observers based on habitat and topography, or this habitat may in fact be better for deer. There may be other factors like food quality that are presently unknown that could better explain deer use or presence at night.

Table 6-3. Habitat use index, W_i, from spotlighted mule deer on the NNSS during 2012

Observed

Habitat

Km of deer route in habitat type

Percent of available habitat (A)

number deer groups

Percent deer use by habitat (B)

Habitat Use Index W_i = B/A

95% CI of

W_i

¹Artemisia spp. Alliance = ARNO-ARTR, ARNO-CHVI, and ARTR-CHVI Shrubland Associations

* Habitats are denoted by an asterisk where selection is significant from 1.0 (i.e., confidence intervals [CIs] did not include 1.0).

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-6.    Mule deer observations by vegetation type on the NNSS

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6.3.4.1       Mule Deer Habitat Use Trends

Trends in the four major habitats used by deer are shown with tendencies for selection and avoidance where Selection = S > 1 and Avoidance = S < 1, with values of W_i significantly different from 1 (Figure 6-7). All other habitats were used relative to availability (W_i = 1).

There is a strong tendency for the Artemisia spp. habitat to be selected in multiple years (three cases in 5 years). In two cases selection was not significantly greater than 1, but deer use was still considerable (Figure 6-7). There is also a strong tendency for the PIMO-ARNO habitat to be avoided over time

(four cases in 5 years). The Miscellaneous-disturbed and PIMO-ARTR habitats show no consistent pattern of use over time. They are both moderately used by deer, often with selection values (three cases for each habitat in 5 years) not different than 1. Trend data suggest that the Artemisia spp. habitat is used more consistently over time than the PIMO-ARTR habitat; therefore, it may be better deer habitat.

Figure 6-7.    Trends in significant habitat selection S > 1, and avoidance S < 1, by deer at the NNSS from 2008 to 2012 (all other points are equivalent to 1 in use)

Ecological Monitoring and Compliance Program 2012 Report

6.4      Mountain Lion Monitoring

6.4.1        Motion-Activated Cameras

Little data exist for mountain lion numbers and their distribution in southern Nevada, including the NNSS. Since 2006, site biologists have collaborated with Dr. Erin Boydston, a research scientist with USGS, to use remote, motion-activated cameras to determine the distribution and abundance of mountain lions on the NNSS. Cameras used this way are referred to as camera traps. Camera traps have also been used the last few years to assist with the capture effort for the telemetry study by identifying where mountain lions occur as well as the frequency of occurrence at those sites. Additionally, camera traps were used during 2012 to assess the number of un-collared and collared mountain lions to estimate their relative abundance.

Remote, motion-activated cameras were used at 33 sites, including 17 new sites (Figure 6-8 and Table 6-4). Sites were selected at locations with previous or new mountain lion sightings or sign, on roads that are potential movement corridors from one area to another, and in areas of good mule deer habitat (mule deer are a primary prey species for mountain lions). The number of images reported is based on a 1-minute interval between images taken during a single episode.

A total of 124 mountain lion images (i.e., photographs or video clips) were taken during 163,487 camera hours across all sites. This equates to about 0.8 mountain lion images per 1,000 camera hours (Table 6-4). Mountain lions were detected at 22 of the 33 sites, including nine canyons, eight dirt roads, one paved road, and four water sources (Figure 6-8).

Table 6-5 gives the camera trap results by month, location, and radio-collared animal, when it was possible to determine which animal was being photographed. All four radio-collared mountain lions captured during 2012 (NNSS4, NNSS5, NNSS6, and NNSS7) were detected with camera traps. Although not conclusive, a photo of NNSS1 (captured during 2011) may have been taken at Gold Meadows Spring during January 2012. The mountain lion in the photograph appears to have a white ear tag in its right ear, which would identify it as NNSS1. This is the same female that had the cub and whose radio collar failed during September 2011. The notch-eared male that had been detected on multiple cameras during 2011 was captured during May 2012 and designated NNSS4. On three occasions, pairs of mountain lions were detected, including two instances where NNSS7 and an un-collared female were traveling together on the same night within 1.5 hours of each other (Site #16 and Site #1). The video clip of the third event (East Gold Meadows Pass, Site #13) was too dark to tell if the two individuals were collared or not. It is difficult to tell individual mountain lions apart in the images and therefore determine the exact number of mountain lions on the NNSS. However, based on the four collared mountain lions and at least two un-collared ones detected with the camera traps, a minimum of six adult mountain lions were detected between June 21 and August 21, 2012, within a relatively small area of 90 km² encompassing the eastern portion of Pahute Mesa (Lambs Canyon and Pahute Mesa Road Summit), Rainier Mesa, Gold Meadows, and Aqueduct Mesa.

In order to investigate temporal activity of mountain lions, camera detection data from all 7 years (2006–2012) were combined. Mountain lions were detected every month with peak occurrences during November (N = 80), and twice as many images during summer and fall (N = 83) compared to winter and spring (N = 41) (Figure 6-9). Mountain lions were detected most frequently between 1700 and 0800 hours, during which more than ten times as many images were recorded (N = 326) compared to between 0800 and 1700 hours (N = 29) (Figure 6-10).

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-8.   Locations of mountain lion photographic detections (N = 22) and motion-activated cameras (N = 33) on the NNSS during 2012

Ecological Monitoring and Compliance Program 2012 Report

Table 6-4. Results of mountain lion camera surveys during 2012

Ecological Monitoring and Compliance Program 2012 Report

Table 6-4.   Results of mountain lion camera surveys during 2012 (continued)

Ecological Monitoring and Compliance Program 2012 Report

Table 6-4.   Results of mountain lion camera surveys during 2012 (continued)

Ecological Monitoring and Compliance Program 2012 Report

Table 6-4.   Results of mountain lion camera surveys during 2012 (continued)

^a Camera hours not known for some time periods.

^b Non-continuous operation due to camera problems, dead batteries, full memory cards, etc.

Ecological Monitoring and Compliance Program 2012 Report

Table 6-5. Number of mountain lion images taken with camera traps by month, location, and animal number, if known

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-9.    Number of mountain lion images by month for camera sites where mountain lions were detected from 2006 through 2012 (N = 360)

Figure 6-10. Number of mountain lion images by time of day (Pacific Standard Time) for camera sites where mountain lions were detected from 2006 through 2012 (N = 355)

A secondary objective of the camera surveys is to detect other species using these areas to better define species distributions on the NNSS. A total of 7,431 images of at least 34 species other than mountain lions were taken during 163,487 camera hours across all sites (Table 6-4). This is about 45 images per 1,000 camera hours. The most prevalent species photographed (60% of all images) was mule deer (4,490 images at 26 of 33 sites). Over 2,000 images of mule deer were taken at Captain Jack Spring. Also noteworthy is 1,278 images of chukar that were taken at Topopah Spring. Some of the rarer, more elusive species documented during camera surveys were desert bighorn sheep (see Section 6.6), bobcat (found at 17 of 33

Ecological Monitoring and Compliance Program 2012 Report

sites), gray fox (Urocyon cinereoargenteus), badger (Taxidea taxus), ringtail cat (Bassariscus astutus), wild burro, Steller’s jay (see Section 4.4), and great blue heron (Ardea herodias). Most (88%) of the photos (6,553 images) were taken at six sites: Gold Meadows Spring (#18), Topopah Spring (#9), Captain Jack Spring (#12), Twin Spring (#21), Camp 17 Pond (#6), and Lambs Canyon Tank (#10). A majority of images were taken during the summer and fall, which emphasizes the importance of these water sources for several wildlife species, especially during the drier months.

6.4.2        Mountain Lion Telemetry Study

A collaborative effort between Dr. David Mattson (USGS), Brian Jansen (trapper), and site biologists continued during 2012 to provide information to assess the risk of human encounters with mountain lions on the NNSS and determine what mountain lions eat and where they make their kills. Information from this effort provides information about their natural history and ecology as well. The NNSS and surrounding areas encompassing the Nevada Test and Training Range (NTTR), Tonopah Test Range, and Desert National Wildlife Range constitute one of the largest areas (over 15,540 km² [6,000 square miles]) in North America where human-caused mountain lion mortality is extremely low, and the size of area is large enough to allow for the emergence of population dynamics likely to typify an unexploited population of lions. This area is also located in some of the driest ecosystems in North America with relatively low prey densities. The goal for 2012 was to capture and radio-collar four mountain lions and track them for approximately 1 year.

Mountain lion trapping occurred from May 17 to June 17. Total trapping effort was 357 trap nights with 1–19 traps each night, with an average of 71 trap-nights per capture. Four mountain lions (three males and one female) were captured and GPS collared, and one male was unintentionally recaptured, for a total of five capture events. Trapping occurred in areas of Rainier Mesa, Pahute Mesa, and Timber Mountain.

A radio collar set to record six locations per day (every 4 hours starting at noon) was fitted on each animal. Body measurements, blood and hair samples (DNA and radiological testing), and a Nebuto strip sample (plague testing) were also taken. Mountain lions were designated as NNSS4, NNSS5, NNSS6, and NNSS7 in order of capture date and were tracked using the satellite GPS radio collars. Locations were recorded by the GPS unit on the radio collar and uploaded via satellite during a certain window of time each day. The data were processed and then sent to site biologists via email. Data were converted to Universal Transverse Mercator coordinates and plotted in ArcMap Version 10.0. Data were searched to identify clusters of locations that were within 100 m of each other typically over a minimum 12-hour period.

Coordinates and maps were printed and taken to the field to search for kill sites. For purposes of this report, a kill site is defined as the area where a mountain lion killed and/or cached its prey. It was difficult to ascertain the exact spot where the prey was killed, but evidence of the kill such as burial sites, the carcass, bone fragments, rumen contents, and hair quite often remained. Once a kill site was found, information about the kill, such as prey species, sex, age, amount consumed, marrow color and consistency, number of burial sites, and dimensions of burial sites, was recorded. Habitat data such as elevation, aspect, slope, landscape position, vegetative cover, and dominant plant species were also documented. Additionally, the number of latrines, scats, and beds was recorded. A field sketch was made detailing where key features were located, and any other pertinent notes were made.

6.4.2.1       NNSS4

NNSS4 was captured on May 23, 2012, near Lambs Canyon on Pahute Mesa (Figure 6-11). It was a healthy, mature 7–9-year-old male that weighed 65 kilograms. It had a notch in its right ear, probably from fighting with another male, which helped biologists determine that this is the same animal as the notch-eared male detected by camera traps during 2011.

NNSS4’s movements were tracked from May 23 to December 31, 2012 (Figure 6-12). The collar was still functioning at this point and data beyond this date will be included in the 2013 annual report. Detailed

Ecological Monitoring and Compliance Program 2012 Report

analyses of habitat use and home range have not been completed yet. However, a rough estimate of NNSS4’s home range is 1,030 km². A study conducted in eastern Nevada between 1972 and 1982 found an average home range size of 580 km² for males (Ashman et al. 1983). NNSS4’s home range is 1.8 times greater than the average found in eastern Nevada. From late May until late October, NNSS4 spent a majority of his time on east Pahute Mesa, Rainier Mesa, Big Burn Valley, the southern Belted Range, Gold Meadows, and Oak Spring Butte. These are the higher elevation areas dominated by single-leaf pinyon pine (Pinus monophylla), Utah juniper (Juniperus osteosperma), basin big sagebrush (Artemisia tridentata tridentata), antelope bitterbrush (Purshia tridentata), and Gambel oak (Quercus gambelii).

Figure 6-11. NNSS4 with notch in right ear, yellow ear tag in left ear, and radio collar. Also pictured is Brian Jansen.

(Photo taken by W. K. Ostler, May 23, 2012)

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-12. Documented locations of NNSS4 (May 23 to December 31, 2012)

Ecological Monitoring and Compliance Program 2012 Report

These areas are also prime mule deer summer habitat. From late October to late December, NNSS4 shifted to lower elevation habitat on Shoshone Mountain, Eleana Range, Argillite Wash, east and west flank of the Belted Range, southern end of Kawich Range, and around the Wildhorse seeps; NNSS4 made one foray during mid-November to Rainier Mesa, Gold Meadows, and the Belted Range. These lower elevation areas contain pockets of high elevation habitat but are dominated by blackbrush, black sagebrush (Artemisia nova), rabbitbrush species (Ericameria and Chrysothamnus spp.), and desert bitterbrush (Purshia glandulosa). This shift to lower elevation corresponds with the timing of migration of mule deer off the mesas to their lower elevation winter range (Giles and Cooper 1985).

Of 49 clusters investigated, prey remains were found at 20 sites (Figure 6-13). A total of 20 individual prey were found, including 14 mule deer (6 bucks, 2 does, 4 fawns, 2 unknown), 5 horse foals (Figure 6-14), and 1 gray fox over a 219-day period from May 23 to December 28, 2012. Two clusters in the Belted Range were not checked due to access restrictions and remoteness. Of these two, one was most likely a mule deer (based on the habitat) kill site because NNSS4 stayed there for a week. The other cluster was considered a possible kill site, and NNSS4 was there for about 16 hours. Taking into account only visited clusters, NNSS4 made a kill, on average, every 11 days with time between kills ranging from 1 to 22 days. Assuming the two non-visited clusters were kills, NNSS4 made a kill, on average every 10 days. Of the 20 kills documented, one was found at a 2-point daytime cluster, one at a 2-point nighttime cluster, two at 3-point nighttime clusters and 16 at ≥4-point clusters. In order to detect all kills, all ≥2-point clusters would need to be checked. In order to detect 90% of kills, ≥3-point nighttime clusters would need to be checked. Time and logistic restraints make it difficult to visit all ≥2-point clusters, so it is suggested that these clusters be visited if feasible with a focus primarily on ≥3-point nighttime clusters.

6.4.2.2       NNSS5

NNSS5 was captured on June 3, 2012, east of Gold Meadows near Rainier Mesa (Figure 6-15). It was a healthy, 3–4-year-old male that weighed 55 kilograms. NNSS5’s movements were tracked from June 3 to November 14, 2012 (Figure 6-16), when the collar malfunctioned and stopped transmitting data. Detailed analyses of habitat use and home range have not been completed yet. However, a rough estimate of NNSS5’s home range is 760 km². This is about 1.3 times greater than the average male home range documented in eastern Nevada (Ashman et al. 1983). From early June until mid-November, NNSS5 spent a majority of his time at higher elevations of the Belted Range, Groom Range, east Pahute Mesa, Gold Meadows, and Oak Spring Butte. During mid-September and mid-October, he used lower elevation habitats on the eastern slope of the Belted Range. The last known location before the collar malfunctioned was at a kill site in Mouse Meadow, just north of Gold Meadows.

Due to logistical constraints and remoteness, only 22 of NNSS5’s clusters were investigated. Kills were found at 14 sites including one double kill (mule deer doe and fawn). Twelve mule deer (two bucks, two does, seven fawns, one unknown), one pronghorn antelope (Figure 6-17), one unknown ungulate

(most likely mule deer), and one unknown carnivore (most likely coyote) were documented (Figure 6-13). The pronghorn antelope kill is of interest because it is the first documented kill of this species on the NNSS, and it is not a very common prey item for mountain lions. An additional four clusters were most likely kill sites as well but could not be checked.

6.4.2.3       NNSS6

NNSS6 was captured on June 10, 2012, in the upper portion of Kawich Canyon (Figure 6-18). It was a 3– 4-year-old female in fair body condition that weighed 34.6 kilograms. Her movements were tracked from June 10 to the first part of August (Figure 6-19) when she was found dead near Pillar Spring on the NTTR. Detailed analyses of habitat use and home range have not been completed yet. However, a rough estimate of NNSS6’s home range for the brief time she was tracked is 257 km², which is 1.4 times greater than the average female home range documented in eastern Nevada (Ashman et al. 1983). The estimated

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-13.    Kill site locations for NNSS4, NNSS5, NNSS6, and NNSS7 by prey type

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Ecological Monitoring and Compliance Program 2012 Report

Figure 6-14. Wild horse foal remains at mountain lion kill site, Area 18

(Photo by D. B. Hall, December 13, 2012)

Figure 6-15. NNSS5 with radio collar and orange ear tag in right ear. Also pictured is Brian Jansen.

(Photo by B. Jansen, June 3, 2012)

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-16. Documented locations of NNSS5 (June 3 to November 14, 2012)

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-17. Pronghorn antelope kill near Gold Meadows Spring, Area 12

(Photo taken by D. B. Hall July 31, 2012)

Figure 6-18. NNSS6 with pink ear tag in left ear and white ear tag in right ear and radio collar. Also pictured is Brian Jansen.

(Photo by B. Jansen, June 10, 2012)

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-19. Documented locations of NNSS6 (June 10 to August 2, 2012)

Ecological Monitoring and Compliance Program 2012 Report

date of death was August 2, 2012, based on movement data from the retrieved GPS radiotransmitter. During June she spent most of her time around Gold Meadows and on Rainier and Pahute Mesas. At the end of June, she headed west and spent the month of July and first couple of days in August in the vicinity of Thirsty Canyon and Pillar Spring. The exact cause of death may never be known. However, it does not appear that she starved to death because she killed at least two mule deer does (June 18 and 24) and two young bighorn sheep (July 1 and 13) at four of the fifteen clusters checked (Figure 6-13). The carcass did not show signs of being attacked by another mountain lion. Results from plague testing at the time of capture were negative, and radiological results at time of capture and post mortem did not show any elevated levels of tritium. The carcass was collected, and it is anticipated that the Nevada Department of Wildlife veterinarian will conduct a necropsy to help determine cause of death.

6.4.2.4       NNSS7

NNSS7 was captured June 17, 2012, on Timber Mountain just west of the NNSS boundary (Figure 6-20). It was a 3–4-year-old male in excellent condition that weighed 56 kilograms. His movements were tracked from June 17 to December 31, 2012 (Figure 6-21). The collar was still functioning at this point and data beyond this date will be included in the 2013 annual report. Detailed analyses of habitat use and home range have not been completed yet. However, a rough estimate of NNSS7’s home range is 894 km², which is 1.5 times greater than the average male home range documented in eastern Nevada (Ashman et al. 1983). NNSS7 spent mid-June through late October on Timber Mountain, Yucca Mountain, Shoshone Mountain, and Rainier and Pahute Mesas. From late October through the end of December, he moved off the mesas and shifted to lower elevation habitat on Yucca Mountain, Shoshone Mountain, Timber Mountain, and Thirsty Canyon.

Figure 6-20. NNSS7 captured on Timber Mountain

(Photo taken by B. Jansen, June 17, 2012)

Ecological Monitoring and Compliance Program 2012 Report

A total of 30 clusters were investigated and prey remains were found at 14 sites (Figure 6-13). At one site, two mule deer bucks had been killed (Figure 6-22). Fifteen prey items were documented including

14 mule deer (9 bucks, 1 doe, 2 fawns, 2 unknown) and 1 desert bighorn sheep over a 197-day period from June 17 to December 31, 2012. Large gaps in data acquisition occurred between June 18 to June 22, June 29 to July 6, and November 9 to 18, which could have resulted in missing clusters to check.

Accounting for only visited clusters, NNSS7 made a kill, on average, every 13 days with time between kills ranging from 5 to 26 days. Assuming four kills were missed during 20 days of missing data, time between kills is 10 days. Of the 15 kills documented, at least 14 were found at ≥4-point clusters and one had missing data for 12 hours after the start of the cluster, so it may have been a ≥4-point cluster as well.

6.4.2.5       Risk to Humans

Only one observation of a mountain lion was reported to NNSS biologists by NNSS workers during 2012. It was seen along Tippipah Highway (Area 12) at 6:30 a.m. on December 11 in an area with several deer. Based on recorded locations for all four radio-collared mountain lions (Figure 6-23), it is evident that these animals prefer rugged, mountainous, typically forested habitat. It is also noteworthy that portions of each collared animal’s home range overlapped on Rainier and Pahute Mesas. From mid-May to late October, they used the higher elevation areas and then moved to lower elevations during November and December and presumably remain there through April or May. This coincides with the migration pattern of mule deer, their primary prey. Very few active projects occur in these areas, so the overall risk of human encounters with mountain lions on the NNSS appears to be quite low. However, at least six individual mountain lions (not necessarily all at the same time) were known to occur on Rainier Mesa and the eastern portion of Pahute Mesa between June and August, and at least two mountain lions used Shoshone Mountain for part of the year. Facilities in these areas include the Calico Hills firing range (Area 25), several tunnel complexes in Area 12 (e.g., G, V, and P Tunnels), and communication towers and power substations in Area 19 (Echo Peak and Pahute Mesa), Area 12 (DOE Point), and Area 29 (Shoshone Mountain). Personnel who work in these mountainous, remote areas (communication and power system maintenance workers, military personnel, etc.), especially at night, are most at risk and should be aware that mountain lions do occur around these facilities.

6.4.2.6       Plague and Radiological Testing

Bubonic plague can be a serious health issue if people are exposed to it. Mountain lions are known to carry the disease and, on rare occasions, have transmitted it to humans. In order to determine if mountain lions on the NNSS carried plague, Nebuto strips blotted with blood taken from NNSS4, NNSS5, NNSS6, and NNSS7 were submitted to the SNHD for plague testing. All samples tested negative for plague.

Blood samples from all four mountain lions were also tested for the presence of tritium, a human-made radionuclide persisting in some portions of the NNSS as a result of nuclear weapons testing. Site biologists wanted to know if mountain lions were being exposed to harmful doses of radiation on the NNSS and the potential dose to a human in the event the mountain lion left the NNSS and was shot and eaten. Detectable levels of tritium (14,491 picocuries/liter [pCi/L]) were only found in NNSS5. This is below the drinking water standard (20,000 pCi/L) set for safe human consumption by the Environmental Protection Agency and should not be harmful to the animal or someone eating the animal (Code of Federal Regulations 2010).

In addition, samples were taken from the remains of nine mule deer and two horses killed by mountain lions and analyzed for tritium content. Two mule deer samples had enough muscle tissue to be analyzed for cesium-137 in addition to tritium. No detectable cesium-137 was found in the two samples, and no detectable tritium was present in either of the horses sampled. Detectable amounts of tritium were found in three mule deer killed by three different mountain lions, NNSS4, NNSS5, and NNSS7. Of most interest is the 7-5 sample killed by NNSS7. The deer was a mature female killed north of the 19-01 Road

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-21. Documented locations of NNSS7 (June 17 to December 31, 2012)

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-22. Two mature bucks killed by NNSS7, Chukar Canyon (Area 30)

(Photo by D. B. Hall, November 27, 2012)

(Area 19) on July 12, 2012 (Figure 6-13). It contained 425,000 pCi/L of tritium, which is more than

20 times the drinking water standard. Although this is a relatively high concentration, the dose received by this animal or any animals eating it is well below any dose expected to be harmful (U.S. Department of Energy 2002). Based on the spatial configuration and timing of deer migration movements relative to known tritium concentrations, the likely source of tritium was UE-20N #1 because more than

61,000 liters of contaminated water was pumped into a sump in late May 2012 with a tritium concentration of 42,836,666 pCi/L. Sample 5-5 was a 2–3-year-old buck killed by NNSS5 in Gold Meadows (Area 12) on July 24, 2012 (Figure 6-13). It contained 26,300 pCi/L of tritium, slightly more than the drinking water standard. Sample 4-11 was a mature mule deer killed north of the 19-01 Road (Area 19) on June 30, 2012 (Figure 6-13). It contained 1,190 pCi/L of tritium, well below the drinking water standard.

These results indicate that mountain lions and mule deer can uptake detectable levels of tritium from the environs of the NNSS by drinking contaminated water or eating contaminated plants and animals. These data also suggest that during dry periods, when animals partially rely on stored water (e.g., contaminated sumps), uptake of tritium can be more prevalent than during wetter periods when ephemeral water is more readily available across the landscape. It is important to underscore the fact that even though tritium was detected in some of the animals sampled, the potential dose to both the animal or other animals, including people, eating it is well below levels considered harmful (U.S. Department of Energy 2002).

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-23. Recorded locations for NNSS4 (blue dots), NNSS5 (yellow dots), NNSS6 (green dots), and NNSS7 (red dots), May 23 through December 31, 2012

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Ecological Monitoring and Compliance Program 2012 Report

6.5         Raptors and Bird Mortality

6.5.1        Raptors

Historically, 16 species of raptors have been recorded on the NNSS. Raptors include vultures, hawks, kites, eagles, ospreys, falcons, and owls. All are protected/regulated under the Migratory Bird Treaty Act and/or Nevada State law. Because these birds occupy the higher trophic levels of the food chain, they are regarded as indicators of ecosystem stability and health. There are nine raptor species known to breed on the NNSS, including the western burrowing owl (Hunter 1994).

6.5.2        Bird Mortality and Compliance with the Migratory Bird Treaty Act

Bird mortality is a measure of impacts that NNSA/NFO activities may have on protected bird species. NNSA/NFO activities that have affected birds typically have been of three types: collisions with buildings, electrocution from power lines, and vehicle mortalities. Workers are relied on to observe and report mortalities. Historically, reported deaths of birds are sometimes numerous, with episodes of predation and disease outbreaks involving larger numbers of dead birds often during wet years

(Figure 6-24).

Figure 6-24. Historical records of reported bird deaths on the NNSS through 2012

Ecological Monitoring and Compliance Program 2012 Report

There were only four reported bird mortalities in 2012; one common raven (Corvus corax) was electrocuted by power lines, one great horned owl (Bubo virginianus) was killed by a vehicle,

one sharp-shinned hawk (Accipiter striatus) was found dead of unknown causes, and one brown-headed cowbird (Molothrus ater) died from getting stuck on a glue trap placed on the floor for pest control. It was concluded that pole lines could be surveyed for bird use prior to the nesting season to help prevent problems from nesting alone. Overall, few impacts to birds were observed and few mortalities were reported from onsite project activities. Impacts to bird populations from NNSA/NFO activities at the NNSS appear to be low.

On December 10, 2012, a raptor nest on a power line pole located in Area 1 was visited and recommended for removal or protection. On December 31, the Power Utilities group, led by Mr. Robert Gang and Facility Manager Michelle Kelly, retrofitted several exposed electrical lines within 1–1.5 m of the previously occupied red-tailed hawk nest. They installed extra electrical insulation on the three energized drop down lines to the transformer boxes (Figure 6-25). This is an example of mitigating a situation where raptors and eagles are at risk of electrocution. This action is the first of its kind and may be recommended at other power poles on the NNSS with nests.

Figure 6-25. Photo of red-tailed hawk nest in Area 1 retrofitted with insulation bushings (top) on electrified lines to reduce electrocution risk

(Photo by R. Gang, December 31, 2012)

Ecological Monitoring and Compliance Program 2012 Report

To reduce electrocutions of eagles and raptors on power line systems, the Avian Power Line Interaction Committee (2006) recommends that the vertical and horizontal distance between any grounded element and any energized element on a power line system be limited to 102–152 cm depending on the position of the elements in question. These recommendations are based on the wingspans, more specifically wrist-to- wrist distance, of raptors and especially eagles, which can reach up to 152 cm length when extended for flight. When raptors land or attempt to fly from a nest/perch, their wings may connect any available ground-to-power or power-to-power elements, which can cause electricity to flow through the bird, causing death. In addition, these situations can also result in costly power outages in the system or even wildland fires. Reducing the number of exposed grounding and electrified elements near bird perching situations should prove to be a win-win situation for the raptors and humans.

6.6         Desert Bighorn Sheep and Elk Sightings

Up until a few years ago, desert bighorn sheep appeared to be rare on the NNSS with only eight recorded observations of their presence on or near the NNSS between 1963 and 2009. These observations were recorded in the southern part of the NNSS (Areas 5, 23, and 25). Motion-activated cameras set at various locations to monitor mountain lions have detected one to three rams at Topopah Spring (Figure 6-8, Site #9) during 2009, 2010, and 2011 and one ram at Chukar Canyon (Figure 6-8, Site #22) on October 26, 2011. Additionally, data from the mountain lion telemetry study documented the presence of ewes and lambs in the Yucca Mountain and lower Fortymile Canyon area during 2011, which suggests there is a previously undetected, resident, reproducing herd of desert bighorn sheep on the NNSS. Between December 25, 2011 and January 2, 2012, 14 photos of three rams were taken by a motion-activated camera at Topopah Spring (Figure 6-8, Site #9). Additional photos, also of a ram, were taken on June 25 (one photo) and September 22 (two photos, one with a mule deer). At a tank in Lambs Canyon on north Pahute Mesa (Figure 6-8, Site #10), a motion-activated camera took 40 pictures of a ram between June 16 and July 4, 2012 (Figure 6-26). On April 18, 2012, six rams were seen in the Mercury Pass area on 200 Hill. These new data have expanded the known distribution of desert bighorn sheep on the NNSS. It is unknown if they have always occurred and just went undetected or if they are colonizing new areas on the NNSS. No desert bighorn sheep were documented to have been killed by radio-collared mountain lions on the NNSS, but NNSS6 killed two young bighorns near Pillar Spring on the NTTR, and NNSS7 killed a bighorn on the west side of Yucca Mountain.

In the future, surveys may be conducted to census the population and determine the residency status of this species on the NNSS. Periodic population counts after getting the baseline population may be used to determine trends in desert bighorn sheep. Desert bighorn sheep are a major game species in Nevada, and hunting units are in close proximity to the NNSS. Characterizing radionuclide burdens of sheep found on site and determining their movement patterns off site into huntable areas is important to assess as a potential dose pathway to humans.

During mountain lion trapping efforts in 2012, Brian Jansen found a partial bull elk skull in the upper portion of Lambs Canyon on May 25. No other elk sightings were documented. Further monitoring will be conducted to determine if elk return to the NNSS.

Ecological Monitoring and Compliance Program 2012 Report

Figure 6-26. Desert bighorn sheep ram at Lambs Canyon Tank

(Photo by motion-activated camera, June 16, 2012)

6.7         Nuisance and Potentially Dangerous Wildlife

During 2012, site biologists responded to 25 calls regarding nuisance, injured, or potentially dangerous wildlife in or around buildings, power lines, and work areas. Problem or injured animals included bats (6 calls), birds (11 calls), coyotes (4 calls), venomous snakes (3 calls), and swarming bees (1 call).

Mitigation measures taken usually involved moving the animal away from people or disposing of dead animals. On several occasions, coyotes were chased out of facilities with an air-soft rifle to try to instill fear of humans in animals that were too comfortable around people because they had been fed. Notices were also communicated via radio, e-mail, safety meeting presentations, and various company publications to alert people to potentially dangerous situations involving wildlife and to remind employees not to feed wild animals on the NNSS.

6.8         Coordination with Biologists and Wildlife Agencies

A site biologist attended the annual Nevada Bat Working Group in December. He is also serving on the White Nose Syndrome Committee of the Western Bat Working Group, which is implementing an action plan to try to prevent White Nose Syndrome from spreading to the western United States, and the Bat Conservation Assessment Committee of the Western Bat Working Group to re-assess the conservation status of bat species in western North America. A site biologist attended the Southwest Partners in Amphibian and Reptile Conservation meetings in Las Vegas in October and presented a paper on western red-tailed skink distribution on the NNSS. A similar paper on western red-tailed skink distribution was also presented at the Nevada Chapter meeting of The Wildlife Society in Reno, Nevada, in January.

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Ecological Monitoring and Compliance Program 2012 Report

7.0            HABITAT RESTORATION MONITORING

7.1             CAU 110, U-3ax/bl Closure Cover

The closure cover for Corrective Action Unit (CAU) 110, U-3ax/bl, located in Area 3 of the NNSS, was completed in the fall of 2000. Following completion, actions were taken to reestablish a cover of native vegetation on the closure cover. Revegetation activities were completed in December 2000. The plant community on the closure cover has been monitored annually since the spring of 2001. Monitoring is performed to document the establishment of a native plant community and to identify any remedial actions that may be necessary to ensure the plant community persists.

Growing season precipitation, which includes precipitation recorded between October 2011 and May 2012 at the BJ Wye weather station, is 4.6 cm or about one-third the average precipitation for this period. This compares to a previous low growing season precipitation of 4.3 cm in 2007 and 4.1 cm in 2002.

There were no major precipitation events during the 2012 growing season. The most precipitation received was a 2-day storm in April when about 1.5 cm of precipitation was recorded.

Precipitation amounts recorded during the first part of the growing season (October to December 2011) was 24% of the average precipitation received during this period. There was a little more precipitation during the next 5 months (January to May 2012), but it was still only 44% of the average amount of precipitation received during this period.

7.1.1        Cover

Plant cover on the closure cover this year was 13% (Table 7-1). Atriplex confertifolia (Shadscale saltbush) cover was 12.6% and Ephedra nevadensis (Nevada jointfir) was 0.4%, accounting for 100% of the total plant cover this year. There were no perennial grasses, forbs, or invasive plants on the closure cover in 2012.

Total plant cover in 2012 was the second lowest recorded over the last 5 years. The 13% shrub cover this year actually represents the second highest cover recorded for shrubs over the last 5 years. Even though plant cover was relatively low this year, it still exceeds the reclamation success standard of 10.2%.

Table 7-1. Percent plant cover and density (plants/m²) on the U-3ax/bl closure cover in 2012. The success standard represents 70% of the cover or density reported for the reference area.

7.1.2        Density

Plant density this year averaged 1.3 shrubs/m² (Table 7-1) and was composed of three perennial native shrubs: A. confertifolia, E. nevadensis, and Krascheninnikovia lanata (winterfat). As in past years

A. confertifolia was the most abundant species present. The only other plants encountered this year were Nevada jointfir and winterfat. A single K. lanata plant was encountered during sampling; however,

Ecological Monitoring and Compliance Program 2012 Report

several others were observed on the closure cover. Perennial grasses have been absent from the closure cover the last 5 years. Forbs and invasive plants are typically present when precipitation is more abundant.

This year is a good example of the importance of the perennial plants on the closure cover. Even in times of extreme drought conditions, perennial plants persist. Total plant density in 2012 was 1.3 plants/m², which is the lowest total density recorded at the U-3ax/bl closure cover site. The highest plant density of 125 plants/m² was recorded just 2 years ago. The average plant density since the site was revegetated is 46 plants/m², and over the last 5 years, plant density has averaged slightly below 36 plants/m². The plant density of 1.3 plants/m² in 2012 exceeds the reclamation success standard (Table 7-1).

7.1.3        Species Richness

The average species richness values over the last 5 years on the closure cover have ranged from a low this year of 1.0 species/quadrat to a high of 7.5 species/quadrat in 2010. This year shrubs accounted for 100% of the 1.0 species/quadrat. There were no perennial grasses on the closure cover this year nor have there been any the last 5 years. Species richness values for forbs have ranged from 0 this year to

4.9 species/quadrat in 2010. It is obvious that the variation in total species richness values over the last

5 years is directly correlated with the presence of forbs (Table 7-2). A. confertifolia and E. nevadensis are the most common shrubs encountered.

Table 7-2. Average species richness for the closure cover and reference site in 2012. Species richness is defined as the average number of different species found within a m² quadrat.

The average species richness value for the reference area averaged for 2010 and 2011 is

4.5 species/quadrat, including 0.7 shrub species/quadrat, 0.2 grass species/quadrat, and 3.6 forb species/quadrat.

The standard for reclamation success based on species richness values in 2012 takes into account values for shrubs and grasses only, because there were no forbs on the reference area this year or on the closure cover. Based on shrubs and grasses, the revegetation success standard would be 0.6 species/quadrat.

Species richness values for the closure cover (Table 7-2) exceed the revegetation success standard in 2012.

7.1.4        Remedial Revegetation

The survival of the 125 shrubs planted at three small areas on the eastern edge of the closure cover was evaluated in May 2012. As of May 2012, 26% of the transplants planted in March 2010 have survived.

K. lanata survival had the highest survival percentage at 45%, followed by Eriogonum fasciculatum (Eastern Mojave buckwheat) (40%) and E. nevadensis (30%). Grayia spinosa (Spiny hopsage) and Chrysothamnus viscidiflorus (yellow rabbitbrush) showed the lowest percentage survival.

Ecological Monitoring and Compliance Program 2012 Report

7.1.5        Summary/Recommendations

The plants that have established on the CAU 110, U-3axbl closure cover continue to show signs of stability. Perennial plant, mainly shrub, cover and density have maintained at essentially the same levels over the last 5 years (Figure 7-1). No significant declines have been noted nor have there been significant increases in shrub cover and density. This year was a unique year in that little precipitation was received at the closure site and there were declines in overall plant cover. The decrease however was due to the complete absence of annual forbs. Shrub cover and density have maintained at about the same levels for the last 5 years. Overall, there are no major concerns for the plant community that has established on the U-3ax/bl closure cover.

Revegetation success this year was based primarily on the cover, density, and species richness for shrubs because they were the only plants present on the closure site and on the reference site. As has been the case in previous years, plant cover on the closure cover exceeded revegetation success standards in 2012. The same held true for plant density and species richness. Revegetation success was based solely on values for shrub cover, density, and species richness. The lack of perennial grasses continues to be the most obvious difference between the plant community on the reference site and on the closure cover.

Perennial grasses were present the first few years after the site was revegetated but have not persisted since then. Grasses are not a major component of the native plant community but they are present.

Invasive weeds can be a concern but not this year. There were no invasive weedy species present on the closure cover or on the reference site this year. There was an absence of annual plants in 2002 and 2007 also.

A few of the transplants used in the revegetation of the new disturbances on the eastern edge of the closure cover are becoming established, although a number of them were lost during additional work at the site.

7.2         CAU 400, Five Points Landfill

In 1997, CAU 400, Five Points Landfill, on the Tonopah Test Range (TTR) was seeded with a mix of native shrubs and grasses. The site was mulched with straw, which was crimped into the soil. The site was protected from grazing animals (e.g., horses and rabbits) with a 1.2-m barbed wire fence and 0.6 m of chicken wire along the base of the fence. A flash flood swept through the site in 2003. The fence was damaged, and much of the vegetation through the center of the site was lost. The fence was repaired, and the site was re-seeded in 2004. The site flooded again in 2006, and much of the lower portion of the site was covered with several inches of sediment. No remedial action was taken.

Monitoring was performed on June 5, 2012. Plant cover and density were recorded, wildlife usage was noted, and erosion was evaluated. Species richness was calculated from density data. The number of different plant species within each quadrat was averaged over all quadrats. This provides an indication of the diversity or heterogeneity of the plant community. Wildlife usage was determined from the presence of animals, burrows, or scat, and browsing by animals. Erosion was measured by observing erosion channels or exposed plant roots.

In 2012, five transects were sampled, two in the area that had not flooded (staging area) and three in the area that was flooded and re-seeded in 2004. The reference area was sampled from 2000 to 2010, and data collected during that period were averaged to determine reclamation success standards.

Ecological Monitoring and Compliance Program 2012 Report

Figure 7-1.   Perennial plant cover on the U-3 ax/bl closure cover. E. nevadensis and A. confertifolia

are the most common shrubs.

(Photo taken by D. Anderson, May 23, 2012)

7.2.1        Plant Cover

Total plant cover on the staging area was a mix of perennial shrubs and grasses (Table 7-3). Atriplex canescens (Fourwing saltbush) was the single shrub species and made up approximately 86% of the total plant cover. Achnatherum hymenoides (Indian ricegrass), a perennial grass, made up the remaining 14% of the plant cover. There were no forbs or invasive weedy species on the site this year. Plant cover on the flooded and re-seeded area was 9% and was made up of one perennial shrub species, A. canescens. There were no perennial grasses or annual forbs, including invasive weeds, on the re-seeded area this year.

The 10-year average for plant cover on the reference area was 17%, which included 8% shrubs, 5% grasses, and 4% forbs. Chrysothamnus greenei (Greene’s rabbitbrush) and A. canescens, two perennial shrubs, made up all the shrub cover. A. hymenoides, the only perennial grass, made up approximately 28% of total plant cover. Although non-invasive forbs and invasive weeds typically make up 23% of total plant cover, there were no forbs or invasive species on the reference area this year.

7.2.2        Plant Density

Total plant density on the staging area was 0.96 plants/m², including 0.73 shrubs/m², 0.20 grasses/m², and

0.03 forbs/m² (Table 7-4). Four perennial species, A. canescens, Picrothamnus desertorum (bud sagebrush), A. hymenoides, and Pleuraphis jamesii (James’ galleta grass), were encountered on the staging area. Forb density, represented by a few Mentzelia albicaulis (whitestem blazingstar) plants, was

0.03 plants/m², indicative of a dry year.

Ecological Monitoring and Compliance Program 2012 Report

Table 7-3. Percent plant cover on CAU 400, Five Points Landfill