Prepared in cooperation with the Nevada Department of Wildlife, Idaho State University, and the 

U.S. Fish and Wildlife Service

Preliminary Analysis of Greater Sage-Grouse Reproduction 

in the Virginia Mountains of Northwestern Nevada

U.S. Department of the Interior

U.S. Geological Survey

Open-File Report 2011–1182
Cover photograph taken by Tatiana Gettelman, U.S. Geological Survey. 
Preliminary Analysis of Greater Sage-Grouse Reproduction 

in the Virginia Mountains of Northwestern Nevada

By Peter S. Coates, Zachary B. Lockyer, Melissa A. Farinha, Joelle M. Sweeney, Valerie M. Johnson, and

Matthew G. Meshriy, U.S. Geological Survey; Shawn P. Espinosa, Nevada Department of Wildlife; 

David J. Delehanty, Idaho State University, and Michael L. Casazza, U.S. Geological Survey

Prepared in cooperation with the Nevada Department of Wildlife,

Idaho State University, and the U.S. Fish and Wildlife Service

Open-File Report 2011–1182

U.S. Department of the Interior

U.S. Geological Survey
U.S. Department of the Interior

KEN SALAZAR, Secretary

U.S. Geological Survey

Marcia K. McNutt, Director

U.S. Geological Survey, Reston, Virginia: 2011

For more information on the USGS—the Federal source for science about the Earth, its 

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Suggested citation:

Coates, P.S., Lockyer, Z.B., Farinha, M.A., Sweeney, J.M., Johnson, V.M., Meshriy, M.G., Espinosa, S.P., Delehanty,

D.J., and Casazza, M.L., 2011, Preliminary analysis of Greater Sage-grouse reproduction in the Virginia Mountains of 

northwestern Nevada: U.S. Geological Survey Open-File Report 2011-1182, 32 p. 

Any use of trade, product, or firm names is for descriptive purposes only and does not imply 

endorsement by the U.S. Government.

Although this report is in the public domain, permission must be secured from the individual 

copyright owners to reproduce any copyrighted material contained within this report.
iii

Contents

Abstract ......................................................................................................................................................................... 1

Project Overview ........................................................................................................................................................... 1

Study Area..................................................................................................................................................................... 2

Methods......................................................................................................................................................................... 2

Monitoring Sage-Grouse............................................................................................................................................ 2

Capturing and Handling.......................................................................................................................................... 2

Radio-Telemetry..................................................................................................................................................... 3

Space-Use ............................................................................................................................................................. 3

Nest Videography................................................................................................................................................... 4

Nest Vegetation Measurements, Nest Site Selection, and Nest Success .............................................................. 4

Brood Monitoring.................................................................................................................................................... 5

Brood Vegetation Measurements........................................................................................................................... 5

Modeling Habitat Selection and Nest Survival........................................................................................................ 5

Predator Monitoring ................................................................................................................................................... 6

Raven and Raptor Surveys .................................................................................................................................... 6

Raven Videography................................................................................................................................................ 6

Badger Surveys...................................................................................................................................................... 6

Preliminary Results........................................................................................................................................................ 7

Radio-Telemetry ........................................................................................................................................................ 7

Space-Use ................................................................................................................................................................. 8

Nest Survival.............................................................................................................................................................12

Selection of Nesting Habitat......................................................................................................................................14

Sage-Grouse Nest Videography ...............................................................................................................................20

Brood Success..........................................................................................................................................................23

Selection of Brood-Rearing Habitat...........................................................................................................................24

Predator Surveys ......................................................................................................................................................27

Preliminary Data Interpretation .....................................................................................................................................29

Acknowledgments ........................................................................................................................................................30

Literature Cited.............................................................................................................................................................31

Figures

Figure 1. Locations of radio-marked sage-grouse in the Virginia Mountains of Nevada ............................................... 8

Figure 2. Utilization distribution of sage-grouse in the Virginia Mountains of Nevada................................................... 9

Figure 3. Utilization distribution of brood-rearing sage-grouse in the Virginia Mountains of Nevada during 2010....... 10

Figure 4. Home ranges (95 percent utilization distribution) of individual sage-grouse in the Virginia Mountains of 

Nevada during the reproductive period........................................................................................................................ 11

Figure 5. The average home range (95 percent utilization distribution) of adult and yearling sage-grouse in the 

Virginia Mountain......................................................................................................................................................... 12

Figure 6. Successful and unsuccessful nests of sage-grouse in the Virginia Mountains ............................................ 13

Figure 7. Mean values (bars represent standard errors) for percentages of understory cover at locations of 

failed and successful nests of sage-grouse in the Virginia Mountains of Nevada during 2009 and 2010 .................... 14

Figure 8. Frequency of use of overhead cover type of sage-grouse nests in the Virginia Mountains during 

2009 and 2010............................................................................................................................................................. 16
iv

Figure 9. Mean values (lines represent standard errors) of percentages of cover by shrub types at

5, 10, 25, 50, and 100-m distances from nest sites and random locations .................................................................. 18

Figure 10. Mean values (lines represent standard errors) of percentages of cover by perennial grass 

and cheatgrass (Bromus tectorum) at nest sites compared to dependent and independent random points................ 19

Figure 11. Mean values (lines represent standard errors) for percentages of cover by perennial and 

annual forbs at nest sites, nest-dependent random points, and nest-independent random points in the 

Virginia Mountains during 2009 and 2010 ................................................................................................................... 20

Figure 12. Images of nest activities at eight sage-grouse nests and one raven nest in the Virginia Mountains of 

northwestern Nevada during 2009 and 2010............................................................................................................... 22

Figure 13. Frequency of documented encounters of species at sage-grouse nests in the Virginia Mountains 

during 2009 and 2010.................................................................................................................................................. 22

Figure 14. Sequence of still photographs from video recordings of a raven attacking a female sage-grouse and 

depredating the eggs within an 8-second period. ........................................................................................................ 23

Figure 15. Mean values for percentages of cover types used by brood-rearing female sage-grouse and 

cover types found at brood-dependent random points................................................................................................. 24

Figure 16. Mean values of percentages of vertical and overall cover for brood locations and brood-dependent 

random locations. ........................................................................................................................................................ 25

Figure 17. Percentages of cover (lines represent standard errors of the means) at day-nesting, night-nesting, and 

brood-dependent random locations over the 50-day post-hatch interval for sage-grouse in the Virginia Mountains 

during 2009 and 2010.................................................................................................................................................. 26

Figure 18. Distribution of point surveys for ravens and raptors across the study areas in the Virginia Mountains of 

Nevada during 2009 and 2010 .................................................................................................................................... 28

Figure 19. Raven nests monitored in 2009 ................................................................................................................. 29

Tables

Table 1. Number of sage-grouse radio tracked in the Virginia Mountains of Nevada, monitored during 

2009 and 2010 and listed by sex and age class ............................................................................................................ 7

Table 2. Mean values for vegetation characteristics of shrub and litter depth at sage-grouse nests and random 

(dependent and independent of nest site) points in the Virginia Mountains of Nevada during 2009 and 2010............ 15
v

Conversion Factors

Multiply By To obtain

Length

centimeter (cm) 0.3937 inch (in.)

meter (m) 3.281 foot (ft) 

kilometer (km) 0.6214 mile (mi)

kilometer (km) 0.5400 mile, nautical (nmi) 

meter (m) 1.094 yard (yd) 

Area

hectare (ha) 2.471 acre

square kilometer (km2) 247.1 acre

hectare (ha) 0.003861 square mile (mi2) 

square kilometer (km2) 0.3861 square mile (mi2)

Mass

kilogram (kg) 2.205 pound avoirdupois (lb)
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1

Preliminary Analysis of Greater Sage-Grouse 

Reproduction in the Virginia Mountains of 

Northwestern Nevada

By Peter S. Coates, Zachary B. Lockyer, Melissa A. Farinha, Joelle M. Sweeney, Valerie M. Johnson, and 

Matthew G. Meshriy, U.S. Geological Survey; Shawn P. Espinosa, Nevada Department of Wildlife; 

David J. Delehanty, Idaho State University, and Michael L. Casazza, U.S. Geological Survey

Abstract

Relationships between habitat selection and population vital rates of greater sage-grouse 

(Centrocercus urophasianus; hereafter sage-grouse), recently designated as a candidate species under 

the Endangered Species Act, within the Great Basin are not well-understood. The growing development 

of renewable energy infrastructure within areas inhabited by sage-grouse is thought to influence 

predator and vegetation communities. For example, common ravens (Corvus corax), a synanthropic 

sage-grouse nest predator, are increasing range-wide and select transmission lines and other tall 

structures for nesting and perching. In the Virginia Mountains of northwestern Nevada, we collected 

preliminary information of space-use, habitat selection, and population vital rates during the nesting and 

brood-rearing period over two years on 56 sage-grouse. Additionally, videography at nest sites (n = 22) 

was used to identify sage-grouse nest predators. The study area is a potential site for renewable energy 

developments (i.e., wind and solar), and we plan to continue monitoring this population using a beforeafter-control-impact study design. The results reported here are preliminary and further data is required 

before conclusions can be drawn from this population of sage-grouse. 

Project Overview

The U.S. Geological Survey (USGS), Nevada Department of Wildlife (NDOW), Idaho State 

University (ISU), and U.S. Fish and Wildlife Service collaborated on an intensive effort to monitor a 

population of Greater Sage-Grouse (Centrocercus urophasianus; hereafter sage-grouse) in the Virginia 

Mountains of northwestern Nevada. A portion of the study area is scheduled for development of wind 

energy and associated transmission infrastructure. Relatively little information is known regarding 

habitat and predator communities of sage-grouse within this area, and these factors may be influenced 

by anthropogenic subsidies. Regulatory agencies consider anthropogenic landscape alterations as 

potential threats to persistence of sage-grouse populations. Field biologists have initiated a before-aftercontrol-impact (BACI) study design to investigate potential positive and negative effects of 

developments on population vital rates and habitat selection. 
2

The purpose of this study was to collect and interpret empirical data before and after 

construction of energy infrastructure to estimate potential effects of threats to sage-grouse populations 

and habitat. This report contains summary data and preliminary findings of 2009 and 2010, which 

represent a portion of the preconstruction years of the ongoing study. It also describes some of our 

future planned efforts related to this study, with respect to monitoring and data analyses. This report 

presents preliminary findings on nest survival, brood survival, and space-use of sage-grouse during the 

reproductive period. Also presented are results of preliminary analyses to identify habitat characteristics 

selected by sage-grouse and factors that influence nest and brood survival. The preconstruction-phase 

findings presented in this report should be interpreted as only preliminary because sample sizes were 

limited.

Study Area

We captured sage-grouse at two lek (defined as a traditional breeding ground) locations in the 

Virginia Mountains during the spring and fall months of 2008–2010. The leks used for capture were the 

only two leks known to be active within the Virginia Mountains. One site was located at Sheep Springs, 

near Fish Springs Ranch on the north slope of the Virginia Mountains. The other was located 

approximately 14 kilometers (km) to the southeast on Spanish Flat, near Tule Peak. The overall study 

area encompassing both leks was approximately 652.7 square kilometers (km2

). 

Dominant plant communities consisted of sagebrush (Artemisia spp.) steppe at lower elevations 

and mountain shrub at higher elevations. Overstory at lower elevations was primarily characterized by 

big sagebrush (A. tridentata spp.). Other shrub cover consisted of Bailey’s greasewood (Sarcobatus

baileyi), horsebrush (Tetradymia sp.), and a variety of rabbitbrush (Chrysothamnus spp.). Overstory of 

mountain shrub communities was characterized by big sagebrush and a variety of mountain shrubs, 

including Saskatoon serviceberry (Amelanchier alnifolia), snowberry (Symphoricarpos albus), and 

antelope bitterbrush (Purshia tridentata). Dominant forbs consisted of woolly mule’s ear (Wyethia 

mollis), lupine (lupines spp.), and arrowleaf balsamroot (Balsamorhiza sagittata). Singleleaf pinyon 

(Pinus monophylla) and Utah Juniper (Juniperus osteosperma) woodlands occurred throughout the 

study area. Grasses included bluebunch wheatgrass (Pseudorogeneria cristatum), crested wheatgrass 

(Agropyron cristatum), Basin wildrye (Leymus cinereus), needle-and-thread grass (Hesperostipa 

comata) and Indian ricegrass (Achnatherum hymenoides). During 1999, a fire near Fish Springs Ranch, 

NV burned >84.8 km2 of sagebrush steppe and mountain shrub communities. Although cheatgrass 

(Bromus tectorum) occurred throughout the study area, the invasive grass was most abundant in burned 

areas.

Methods

Monitoring Sage-Grouse

Capturing and Handling

We located sage-grouse after sunset and before sunrise with spotlights and used nets attached to 

3-meter (m) extension handles (Wakkinen and others, 1992) and hand-held net-launching devices 

(SuperTalon®, Advanced Weapons Technology, La Quinta, Calif.) to capture sage-grouse. Birds were 

equipped with battery powered necklace-style radio transmitters (less than 3 percent body mass, weight 

of bird was 1–1.8 kilograms [kg]; Schroeder and others, 1999; Advanced Telemetry Systems, Isanti, 

Minn.). Sage-grouse were also weighed, and multiple length measurements, including tarsus and 
3

culmen, were recorded to generate a body condition index. Blood was extracted from the brachial vein 

for deoxyribonucleic acid (DNA) analyses. We determined age based on plumage (Ammann, 1944). 

During spring months, sage-grouse were classified as either adult (AD) or yearling (AHY). During fall 

months, sage-grouse were classified as AD or hatch-year (HY). Age classifications were based on 

plumage characteristics of the 9th and 10th primaries. Plumage photographs (including wings extended, 

retrices, as well as breast and head profile poses) were taken of each sage-grouse prior to release at its 

location of capture.

Radio-Telemetry

We monitored sage-grouse movement, survivorship, and reproduction following release

throughout the spring and summer months (March 15 – 05 August). We used a 3-element Yagi antenna 

and portable receiver (Communication Specialist Inc. Orange, Calif.; Advanced Telemetry Inc., Isanti, 

Minn.) to track radio-marked sage-grouse, and we minimized relocation error by encircling each sagegrouse by using a 30–50 m buffer to pinpoint the bird’s location. After pinpointing the bird being 

tracked, we approximated the distance and a compass bearing from a known location (recorded by using 

global positioning system [GPS] equipment) to obtain the location coordinates (Universal Transverse 

Mercator) of the bird’s location. Throughout the nesting and brood-rearing periods, we attempted to 

locate female sage-grouse at least twice per week.

Space-Use

The coordinates of the relocation points were plotted into a geographical information system 

(GIS) (ArcGIS 9.2, ESRI Products, Redlands, Calif.) for space-use analysis. We conducted three

analyses by using kernel density estimations for the spring and summer months. The kernel density 

estimates provide a measure of the utilization distribution (UD) of sage-grouse across the landscape 

(Worton, 1989). Thus, utilization distributions are useful to visualize where on the landscape sagegrouse were frequently relocated. In the first analysis, we calculated the amount of area within the upper 

50 and 95 percent contours of the highest density region based on the entire relocation dataset (pooled 

across individuals). We considered the 50 percent contour as the core area and the 95 percent contour as 

home range. The purpose of using the pooled dataset was to estimate area used at the population level. 

The kernel density calculations were carried out in multiple steps. The relocation points were weighted 

to account for biases associated with nonequivalent relocation intervals. We calculated the smoothing 

parameters (h) by using least-squares cross validation in Animal Space Use 1.3 (Horne and Garton,

2009), which minimized the difference in volume between the true UD and the estimated UD. We 

imported those smoothing parameters into a GIS (ArcGIS 9.2) and used Hawth’s Tools (Beyer, 2004) to 

calculate fixed kernel densities. Kernel density maps were generated based on the estimated densities 

for 2009 and 2010. In the second analysis, we calculated kernel density estimates for each individual 

sage-grouse by using the same steps described above. We only calculated estimates for an area within 

the upper 95 percent contour of the highest density for individuals. In the third analysis, we examined 

areas used by brood-rearing sage-grouse by calculating 95 percent kernel density estimates for only 

sage-grouse with broods during the brood-rearing period. 
4

Nest Videography

When a radio-marked sage-grouse was found at the same location multiple times during the 

early nesting period, we visually determined if the sage-grouse was nesting (Coates and Delehanty,

2010). Nests were monitored ≥3 times per week until their fate was determined. Nests were classified as 

successful when one or more chicks hatched. Nests were also scored as depredated, partially depredated, 

or abandoned. In addition to monitoring nests with radio telemetry, we installed camouflaged 

microcameras with time-lapsed digital video recorders (DVR) on 6 and 16 nests during 2009 and 2010, 

respectively. The primary purpose of cameras was to identify nest predators (Holloran and Anderson,

2003; Coates and others, 2008). Another purpose was to identify factors that influence patterns of 

incubation (Coates and Delehanty, 2008). Cameras were placed approximately 0.5 m from the nest 

bowl, which aided in unambiguous identification of animal encounters and sage-grouse behavior. 

Cameras and video recorders were uninstalled immediately following nest predation, abandonment, or 

hatch. We sought to reduce human scent by wearing rubberized gloves and using spray designed to 

mask scent.

Nest Vegetation Measurements, Nest Site Selection, and Nest Success

Following nest fate, we recorded understory cover at the nest bowl by using three techniques, 

including a coverboard (modified from Jones, 1968), a Robel pole (Robel and others, 1970), and a

digital photographic method. The purpose of using three techniques was to compare the results obtained 

by each method. Measurements using a cover board were conducted at 2-m from the point and 0, 45, 

and 90 degree angles from the ground. We categorized vertical cover as measurements at 0 and 45 

degree angles and overall cover as those at all three angles. We also measured composition of 

vegetation cover at five subplots (20 × 50 centimeters [cm]) located ≤25 m of each nest by using the 

Daubenmire method (Daubenmire, 1959). After randomizing the orientation of the quadrant, we 

measured canopy cover along two 25-m transects, one 50-m transect, and one 100-m transect, all

extending from the nest bowl at 90° intervals. We recorded shrub species and measured and recorded 

width (cm) and heights (cm) of a random sample of individual shrubs along the line. These shrub widths 

were measured within 5, 10, and 25 m from the nest for all four transect lines, within 50 m for two 

transect lines, and 100 m for one transect line. The purpose of the different transect lengths was to 

identify the scale where selection for shrub cover occurs at nest sites. We also used a GIS to measure 

multiple explanatory variables within the landscape (ArcGIS, ESRI software, Redlands, CA). We 

classified features across the study areas as multiple dominant cover types, including sagebrush steppe

shrubland, riparian, meadow, agriculture, perennial grassland, annual grassland, sagebrush steppe 

interspersed with pinyon-juniper woodlands, and pinyon-juniper woodland.

To examine nest site habitat selection, defined as habitat use disproportionate to availability

(Hall and others, 1997), we compared means and variance of measurements of vegetation characteristics 

at nests to those at random points. To characterize available habitat, we generated random points 

throughout the study site and conducted the same habitat measurements at those locations centered at 

the nearest shrub. Habitat characteristics at random locations were then compared to those at nest 

locations. We evaluated evidence for multi-scale selection by generating two random points for each 

nest. One point was within 500 m of the nest (dependent random point) and the other was within the 

study area (independent random point). The preliminary results were reported as means (± standard 

error of the mean [SE]) of vegetation characteristics for random points and nests. 
5

Nests were scored as successful if ≥1 egg hatched. We estimated daily nest survival parameters 

using maximum likelihood procedures in Program R with the package RMark (Laake and Rexstad 

1999). We report apparent nest success and maximum likelihood derived survival rates.

Brood Monitoring

Following the completion of a successful nest, we obtained locations of monitored radio-collared 

female sage-grouse with broods two or more times per week. Every 10 days following nest hatch, we 

used spotlights during night surveys to count the number of chicks in each brood. To confirm an 

unsuccessful brood (and prevent a false negative), females were re-spotlighted for brood presence 

within 48 hours of finding a female with no brood. 

Brood Vegetation Measurements

We conducted a similar habitat measurement protocol at brood sites as was conducted at nest 

sites; however, maximum extent of the transect line was 25 m for brood sites. To determine exact brood 

locations for habitat measurements, the exact point of the resting female sage-grouse was recorded with 

a photograph or the distance and direction were noted from a distinct feature on the landscape in the 

immediate area of the sage-grouse. Canopy cover was measured along three 25-m transects extending

from the brood location every 120°, with random orientation. We measured the width (cm) of each 

shrub species along the three transect lines within 5, 10, and 25 m from the brood location. Because 

habitat changes through time and broods are mobile, we conducted measurements at each 10-day 

interval. We also investigated differences in vegetation use between night (roosting) and day (foraging) 

hours. These surveys included one day and one night observation of habitat used by females with broods 

(within a 24-hour period), as well as one observation of a random location within 850 m of the brood 

(dependent) to estimate disproportionate use to availability.

Modeling Habitat Selection and Nest Survival

We plan to extend these survival and selection analyses into a modeling framework after 

obtaining greater sample sizes (Casazza and others, in press). For example, generalized mixed-effects 

models at different spatial scales (that is, grain and extent) will be developed and evidence for models 

will be evaluated for habitat selection and survival of nests and broods. We chose explanatory variables 

(e.g., vegetation type) for each dependent variable to include in the models based on a priori

information that represents competing hypotheses about habitat selection and survival. Resource 

selection functions (RSF) will be calculated from the used-available data (Manly and others, 2002) 

using model parameter estimates during the nesting and brood-rearing period. The RSF approximates 

the probability that a resource of type xi is selected once it is encountered and provides a valuable 

measure of relative selection between resources of different types. We plan to use multiple parametric 

link functions (e.g., exponential and logistic) to identify the model that best describes the data. Random 

effects will be fit where we find evidence of support within the models to represent spatial and temporal 

correlation between sample units. We will use an information-theoretic approach (Anderson, 2008), 

including the [Delta] Akaike information criterion (∆AIC) measure, Akaike’s weights, and evidence 

ratios. We will also apply likelihood-based coefficient of determination (R2) values and likelihood ratio 

tests to evaluate evidence between the competing a priori models. We will average parameter estimates 

across models to identify factors that influence selection and survival.
6

Predator Monitoring

Raven and Raptor Surveys

Because ravens are known to be an effective sage-grouse nest predator (Coates and others, 2008; 

Bui and others, 2010; Coates and Delehanty, 2010), and raptors are known to consume sage-grouse 

(Moynahan and others, 2006), we conducted surveys for Common Ravens (Corvus corax; hereafter 

ravens) and raptors during sage-grouse nesting and immediately following determination of nest fate. 

We conducted visual surveys (using binoculars) for each sage-grouse nest location from a distance of 

approximately 50–100 m from the incubating female. Surveys were conducted over a 15-minute period 

wherein all four cardinal directional quadrants around the nest were searched for equal time allotments. 

Time of sighting, bearing, and distance (estimated by using a rangefinder) of each raptor and raven was 

tallied and identified to species when possible. 

We plan to model factors that influence raven and raptor population numbers, particularly in 

relation to energy infrastructure, using surveys that were conducted at random locations across the study 

area following data collection after energy development. Randomization of survey points across the 

study area will be critical in assessing impacts to sage-grouse populations. Points were generated both 

on and off undeveloped roads. Surveys were completed between mid-May and late-July. Surveys were

carried out between one half hour before sunrise and one half hour following sunset. The same protocol 

for nest surveys was carried out at random survey points. Point surveys randomized within the study 

area will be used to estimate raven and raptor densities by using Program Distance (Thomas and others,

2010) across the landscape. 

Raven Videography

We collected additional observational data on raven nests by using videography within the study 

area. The objectives for using videography included: (1) to investigate links between raven foraging 

activities and sage-grouse incubation patterns, (2) to estimate provisioning rates of raven nestlings, and 

(3) to identify components of the raven nestling diet. We plan to investigate differences between nests in 

anthropogenic and natural nesting substrates. Information gathered in this study will assist with future 

implementation techniques for wildlife management concerning raven and sage-grouse interactions. 

This information may be particularly useful in areas of energy development because ravens are often 

associated with anthropogenic resource subsidies, such as transmission towers and lines (Boarman,

2003; Bui and others, 2010).

Badger Surveys

Following the fate of the nest (hatched, abandoned, or depredated) and the sage-grouse had 

departed the nest site, we conducted surveys for American badger (Taxidea taxus; hereafter badger). We 

inspected a 4-m wide transect line that formed a bowtie pattern centered on the nest bowl. The total 

searching distance was 680 m. Badger surveys were conducted at all nest, dependent, and independent 

random points. Within each of the survey lines we detected and recorded fresh, intact badger holes;

collapsed holes; small digs or scrapes; badger scat; or tracks. These measurements were used to develop 

a badger activity index. 
7

Preliminary Results

Radio-Telemetry

Fifty-six sage-grouse were fitted with radio-transmitting collars from fall 2008 through June 

2010 (table 1). In 2009, 24 female and 5 male sage-grouse were tracked by radio telemetry. In 2010, 23 

female and 4 male sage-grouse were tracked. Three replacement collars were deployed during 2010 on 

sage-grouse captured during the fall of 2008. Most sage-grouse were relocated in the Spanish Flat area 

(fig. 1). 

Table 1. Number of sage-grouse radio tracked in the Virginia Mountains of Nevada, monitored during 2009 and 

2010 and listed by sex and age class. 

Sex Age 2009 2010

Males Adult 4 1

Yearling 1 3

Females Adult 18 12

Yearling 6 11

Total 29 27
8

Figure 1. Locations of radio-marked sage-grouse in the Virginia Mountains of Nevada. A, During 2009. B, During

2010.

Space-Use

During 2009, the core area of sage-grouse activity (50 percent UD) was 2,320 hectares (ha)

(fig. 2) according to pooled radio-location points. The home range (95 percent UD) at the population 

level encompassed 17,650 ha. During 2010, the core area was 1,930 ha, and the population-level home

range encompassed 13,180 ha. In both years, the core area was located at Spanish Flat. Following 

successful nesting, brood-rearing females and male sage-grouse from both lek sites used this area before 

moving to wintering areas. In 2010, the core area of only brood-rearing sage-grouse was 700 ha, with a 

home range of 2,600 ha (fig. 3). The majority of individual home ranges throughout spring and summer 

overlapped within the Spanish Flat area, resulting in much less use of the Sheep Springs area (fig. 4), 

relatively speaking. Average home range size for individual sage-grouse was 2,470 ha ± 370 ha. Adult 

home range (2,870 ± 515 ha) was substantially greater than AHY (1,620 ha ± 300 ha), most notably in 

2010 (fig. 5).

A B
9

Figure 2. Utilization distribution of sage-grouse in the Virginia Mountains of Nevada. A, During 2009. B, During

2010. (Utilization distribution was approximated by using kernel density estimators). 

A B
10

Figure 3. Utilization distribution of brood-rearing sage-grouse in the Virginia Mountains of Nevada during 2010.

(Utilization distribution was approximated by using kernel density estimators).
11

Figure 4. Home ranges (95 percent utilization distribution) of individual sage-grouse in the Virginia Mountains of 

Nevada during the reproductive period. A, In 2009. B, In 2010. 

A B
12

Figure 5. The average home range (95 percent utilization distribution) of adult and yearling sage-grouse in the 

Virginia Mountains (shown for 2009, 2010, and pooled [averaged across years]).

Nest Survival

We monitored 39 sage-grouse nests during 2009 and 2010 (fig. 6). Based on maximum 

likelihood estimation, nest survival was 13.5 percent (Confidence Interval; 8.9–20.2 percent) with a 37-

day exposure period (laying and incubating). The estimated daily survival rate was 94.7 ± 1.1 percent. 

We documented 12 successful nests (first nest attempt = 9, second attempt = 3) and 27 failed nests (first 

= 25, second = 2), of which 24 were depredated (first =22, second = 2) and 3 first nests were abandoned. 

Two nests were partially depredated, but hatched 1 chick or more. One female died before nesting and 

another female slipped her radio-collar and we were unable to find her throughout the remainder of the 

season. Furthermore, signals were lost on three female sage-grouse during the nesting period, perhaps 

because of radio failure or movement away from the study region. The remaining radio-collared female 

sage-grouse did not attempt to nest, or nests were depredated prior to researcher detection (during the 

laying period). We did not document third nesting attempts.

0

5

10

15

20

25

30

35

40

2009 2010 Pooled

Adult

Yearling

Average Home Range (Square Kilometers)
13

Figure 6. Successful and unsuccessful nests of sage-grouse in the Virginia Mountains. A, During 2009. B, During

2010.

On average, we measured greater vegetation understory cover by using the coverboard at 

successful nests (52.5 ± 2.7 percent) than at unsuccessful nests (41.0 ± 2.3 percent; fig. 7). Nest 

vegetation cover is currently being analyzed using the photographic method. We plan to compare results 

between field methodologies. We did not detect any other microhabitat factors important to nest 

survival. Preliminary results generated using a GIS suggested that unsuccessful nests were generally 

associated with greater areas of invasive grassland vegetation types, mostly consisting of cheatgrass 

(Bromus tectorum); however, additional data and analyses are needed to fully understand microhabitat 

and landscape factors that explain variation in nest survival (for example, canopy cover, cover type, and 

the number of predators). Nest locations ranged in elevation from approximately 1,500 to 2,100 m. 

During the final analyses of the study, we plan to include environmental covariates, such as vegetation 

measurements and time-dependent effects, into sage-grouse nest survival models. 

A B
14

Figure 7. Mean values (bars represent standard errors) for percentages of understory cover at locations of failed 

and successful nests of sage-grouse in the Virginia Mountains of Nevada during 2009 and 2010. 

Selection of Nesting Habitat

Nests were nearly always located under the canopy of shrub vegetation. The maximum height of 

nest shrubs averaged across nests was 76.1 ± 4.4 cm (range, 50–129 cm). The greatest width of nest 

shrubs averaged 117.5 ± 5.8 cm (83–170 cm), and the perpendicular width averaged 88.1 ± 5.1 cm (51–

150 cm). The base of nests was comprised of litter placed on the ground. The average depth of the litter 

was 2.3 ± 0.2 cm (1–4 cm). Our preliminary findings suggest nest shrubs had greater height and width 

than shrubs measured at random dependent locations (table 2); however, we did not find a difference in 

shrub height and width at nest sites and random independent points. These preliminary findings indicate 

that sage-grouse are selecting nest shrubs with greater heights and widths within the immediate area (or 

on a local scale) (500 m from nest) only. 

Females nested underneath the canopy of numerous shrub species, and one female was found 

nesting under a rock outcrop (fig. 8). The most frequently used shrubs were sagebrush (25 percent) and 

rabbitbrush (20 percent). Other vegetation included Bailey’s greasewood, horsebrush, rabbitbrush, 

serviceberry, snowberry, and Great Basin wildrye.

0

10

20

30

40

50

60

Failed Successful

Mean Percent Cover

Nest Fate

Mean percentage of cover
15

Table 2. Mean values for vegetation characteristics of shrub and litter depth at sage-grouse nests and random 

(dependent and independent of nest site) points in the Virginia Mountains of Nevada during 2009 and 2010.

[Numbers in parentheses represent standard errors of the means; D, dependent of nest site; I, independent of nest site]

Point

Greatest

height 

(cm)

Greatest 

width 

(cm)

Perpendicular 

width 

(cm)

Litter 

depth

(cm)

Nest 76.1 (4.4) 117.5 (5.8) 88.1 (5.1) 2.3 (0.2)

Random (D) 64.4 (4.7) 104.0 (9.0) 82.4 (7.2) 1.6 (0.5)

Random (I) 75.5 (2.8) 114.1 (6.7) 89.5 (5.0) 2.7 (0.5)
16

Figure 8. Frequency of use of overhead cover type of sage-grouse nests in the Virginia Mountains during 2009 and 

2010.

0

1

2

3

4

5

6

Frequency of Nesting 
17

Our preliminary results suggest sage-grouse did not select areas with greater sagebrush cover 

(fig. 9), even though sagebrush was often selected as the nesting shrub; however, other species of shrub 

appeared to be selected by sage-grouse (fig. 9). The percentage of sagebrush cover remained relatively 

consistent as the distance from the nest increased. The average sagebrush cover was 1.6 ± 0.07 percent

(fig. 9). Of the total cover within 100 m of nests, 12.4 ± 0.6 percent was comprised of sagebrush species 

and 87.6 percent was nonsagebrush species. In comparing nest locations with random dependent 

locations (within 500 m from nests), 21 ± 10.3 percent more sagebrush was available at random 

locations than was used by sage-grouse. In comparing nest locations with random independent locations 

(those at the study site level), 48.5 ± 12.0 percent more sagebrush was available than was used by sagegrouse. 

Our preliminary results suggest females select perennial grass for their nest sites, while avoiding 

annual grasses, especially cheatgrass, at proximities of 10 m or less from the nest (fig. 10). This effect 

was reduced at a distance of 25 m from the nest. When comparing the available habitat points, we found 

evidence for cheatgrass avoidance at both spatial scales (dependent and independent) within 10 m. The 

dependent random points had similar percentages of cover by perennial grass (12.6 ± 4.6 percent) as the 

area selected for nesting by sage-grouse (13.4 ± 2.5 percent); however, less perennial grass occurred at 

the independent location (8.6 ± 2.4 percent; availability at the study site level) compared to the used 

location within 10 m. Female sage-grouse did not appear to select for nest sites with more or less annual 

or perennial forbs (fig. 11). 
18

Figure 9. Mean values (lines represent standard errors) of percentages of cover by shrub types at 5, 10, 25, 50,

and 100-m distances from nest sites and random locations. A, Sagebrush (Artemisia spp.). B, Other shrubs. C,

Total shrubs. Percentage of cover was cumulative with an increase in distance. 

0

2

4

6

8

10

12

14

16

18

Sagebrush Cover (%)

Used

Random (D)

Random (I)

0

2

4

6

8

10

12

14

16

18

Other Shrub Cover (%)

0

2

4

6

8

10

12

14

16

18

5 10 25 50 100

Total Shrub Cover (%)

Distance from Nest (m)

Percentage of sagebrush cover Percentage of other shrub cover Percentage of total shrub cover

A

B

C
19

Figure 10. Mean values (lines represent standard errors) of percentages of cover by perennial grass and 

cheatgrass (Bromus tectorum) at nest sites compared to dependent and independent random points. A, Cover 

values around the nest. B, Cover values at 10 m from the nest. C, Cover values at 25 m from the nest. 

0

5

10

15

20

25

Used

Random (D)

Random (I)

a. Nest (0 m)

0

5

10

15

20

25

Mean Percent Nest Cover

b. 10 m from nest

0

5

10

15

20

25

Perennial Grass Cheatgrass

Grass Type at 25m from Nest

c. 25 m from nest

Mean percentage of nest cover

A

B

C
20

Figure 11. Mean values (lines represent standard errors) for percentages of cover by perennial and annual forbs at 

nest sites, nest-dependent random points, and nest-independent random points in the Virginia Mountains during 

2009 and 2010.

Sage-Grouse Nest Videography

Twenty-two nests were video-monitored during 2009 (n = 6) and 2010 (n = 16). Four ravens, 

two badgers, two coyotes (Canis latrans), and one bobcat (Lynx rufus) were identified depredating nests 

by videography (n = 9; figs. 12 and 13). 

Ravens

We captured four raven predations on video during daylight hours. Sage-grouse usually were 

flushed during these events. On one occasion, an incubating sage-grouse was attacked. Nest defense by 

each female sage-grouse was unsuccessful, and all eggs were either directly destroyed by ravens or 

abandoned after the event took place.

Badger, Coyote, and Bobcat

Badgers were responsible for one nest predation each year of the study. The two coyote and the 

single bobcat predation occurred in 2010, and all three of these predators depredated sage-grouse nests 

during night hours.

0

5

10

15

20

25

Perennial Forb Annual Forb

Mean Percent Cover 

Forb Type at Nest

Used

Random (D)

Random (I)

Mean percentage of nest cover
21

Weasel

We have no records of a successful predation by long-tailed weasels (Mustela frenata); however, 

on one night, a weasel attacked a female sage-grouse while her nest was hatching. Although the female 

sage-grouse tried to defend the eggs, all unhatched eggs were destroyed. The female sage-grouse fled 

with one chick that ultimately survived. The weasel was not subsequently observed eating or removing 

eggs or chicks from the nest it had originally attempted to depredate (USGS unpublished data).

Gopher Snake 

We observed no successful egg predation events by snakes. In 2009, one relatively large gopher

snake (Pituophis catenifer) was documented unsuccessfully attempting to swallow a sage-grouse egg for 

more than two hours. Another snake successfully captured and consumed a single hatched chick in a 

nest bowl. In this instance, the female sage-grouse left the nest with multiple chicks and did not return.

Ground Squirrel 

California ground squirrels (Spermophilus beecheyi) have been the only species of squirrel to 

visit sage-grouse nests at the study area, and none have successfully depredated eggs. A ground squirrel 

was documented at a nest following a raven predation. The squirrel entered the nest bowl approximately 

ten hours after the female sage-grouse was flushed by the raven. Several minutes passed while the 

squirrel unsuccessfully attempted to bite into the egg. It appeared that the squirrel was limited by the 

width of its gape. One squirrel appeared to incidentally break open an egg after lifting and dropping it, 

at which time the squirrel consumed the egg’s content. We have not documented rodents capable of 

flushing sage-grouse from their nests and consider the incidental egg breaking by the California ground 

squirrel a rare occurrence.

Hatches 

Ten successful nest hatches were captured on video.

Abandonments 

We recorded three nest abandonments. One abandonment appeared to be related to an injury to 

the wing of the incubating female. During maintenance visit to the nest to replace batteries and a 

memory card, the female sage-grouse was observed falling out of flight with an apparent injured wing. 

We recaptured the bird and discovered a broken or dislocated left humerus with collision abrasion to the 

wing. The injury showed evidence of collision with a metal structure and was not consistent with any 

known predator attack pattern of damage. We suspect the female collided with a guy-wire or post from 

the nearby meteorological tower (which happened to be within 200 m of her nest) because this 

anthropogenic structure was the only proximate tall structure capable of internal and external tissue 

damage. Following release, video monitoring documented the female frequenting the nest with irregular 

incubation recesses. She laid 9 eggs but eventually abandoned the nest. The sage-grouse was not 

capable of flight, and an unknown predator killed and consumed her within 21 days of injury. Another 

occurrence of abandonment appeared to be related to adverse weather conditions where snowfall buried 

the female and she subsequently abandoned her nest. The reason for the third nest abandonment was 

unknown.
22

Figure 12. Images of nest activities at eight sage-grouse nests and one raven nest in the Virginia Mountains of 

northwestern Nevada during 2009 and 2010. A, A female sage-grouse incubating. B, A coyote depredating a nest.

C, A California ground squirrel manipulating an egg after a raven predation. D, A weasel that attacked sage-grouse.

E, A raven feeding her young. F, A bobcat depredating a nest. G, A badger depredating a nest. H, A raven 

depredating a nest. I, An unsuccessful attempt by a gopher snake to consume eggs. 

Figure 13. Frequency of documented encounters of species at sage-grouse nests in the Virginia Mountains during 

2009 and 2010. 

0

1

2

3

4

5

Gophersnake 

(Pituophis 

catenifer)

Long-tailed 

Weasel 

(Mustela 

frenata)

American 

Badger 

(Taxidea 

Taxus)

Bobcat (Felis 

rufus)

Coyote 

(Canis 

latrans)

Common 

Raven 

(Corvus 

corax)

Frequency of Predation

A

B C D E

F G H I
23

Figure 14. Sequence of still photographs from video recordings of a raven attacking a female sage-grouse and 

depredating the eggs within an 8-second period. A, The female incubating prior to being struck by the raven. B,

Harassment of the sage-grouse by the raven. C and D, Female sage-grouse fleeing the nest. E and F, The raven 

depredating the eggs.

Brood Success

Brood success was defined by one chick or more alive at 50 days post-hatch. In 2009, brood 

success was 100 percent (at 50 days). We observed a female mortality with a brood prior to 30 days 

post-hatch in 2009 (unknown brood outcome). Of the nine broods in 2010, one failed by 40 days and 2 

failed by 50 days post-hatch. 

In both years, female sage-grouse moved with their broods to the higher elevations (often ridge 

tops) than during the nesting period. Those sites were generally characterized by relatively less grass 

and shrub canopy cover. During late July of both years, we observed females joining other sage-grouse

where brood mixing occurred. Groups sometimes consisted of more than 20 individuals. Once female 

sage-grouse were in larger groups, it was often challenging to obtain chick counts for distinct females.

During 2010, broods moved 455 ± 146.7 m between day and night observations that were conducted 

within a 24-hour interval (n = 23). In one instance, a female sage-grouse and her brood were found 

during the night at a location 3.6 km away from the daytime location. 

A B C

D E F
24

Selection of Brood-Rearing Habitat 

Our preliminary results showed evidence of selection for perennial forbs (used = 16.5 ± 1.5

percent; random = 10.9 ± 1.8 percent) but no selection for annual forbs (used = 5.6 ± 0.4 percent;

random = 5.6 ± 0.5 percent). We also found some evidence of selection for perennial grass (used = 10.3 

± 1.2 percent; random = 8.4 ± 1.2 percent). Brood-rearing females did not appear to avoid cheatgrass

(used = 6.6 ± 1.3 percent, random = 6.6 ± 1.6 percent), as they did during the nesting period (fig. 15).

Brood-rearing sage-grouse selected areas with greater vertical cover, measured by the cover 

board, than would be expected to occur at random points (fig. 16); however, sage-grouse did not appear 

to select areas with greater horizontal cover, measured by sagebrush canopy, through time (fig. 17). The 

random surveys indicate that sagebrush was available in areas where broods were located, yet sagegrouse appeared to not use areas of greater sagebrush cover. We found that shrub cover other than 

sagebrush was selected during the day (foraging) but not during the night (roosting; fig. 17). Brood day 

locations had 99.6 percent more total shrub-canopy cover than did brood night locations.

The relationship between day and night canopy cover and the species composition of vegetation

appeared consistent throughout the 50-day post-hatching interval (fig. 17). It appeared that at 50 days, 

when the chicks from broods are relatively large and capable of sustained flight, less shrub cover was 

selected in daytime relative to what was available. The variation was relatively greater for samples at 50 

days than at earlier intervals. 

Figure 15. Mean values (lines represent standard errors) for percentages of cover types used by brood-rearing 

female sage-grouse and cover types found at brood-dependent random points.

0

5

10

15

20

25

30

35

40

45

Mean Percent Cover

Cover Type

Used

Random

Mean percentage of cover
25

Figure 16. Mean values (lines represent standard errors) of percentages of vertical and overall cover for brood 

locations (open bars) and brood-dependent random locations (dark bars).

0

10

20

30

40

50

60

70

Vertical Cover Overall Cover

Mean Percent Cover

Cover Type

Used

Random

Mean percentage of cover
26

Figure 17. Percentages of cover (lines represent standard errors of the means) at day-nesting, night-nesting, and 

brood-dependent random locations over the 50-day post-hatch interval for sage-grouse in the Virginia Mountains 

during 2009 and 2010. A, Percentage of cover by sagebrush (Artemisia tridentata). B, Percentage of cover by other 

shrub types. C, Percentage of cover by all shrubs.

0

5

10

15

20

25

30

35

40

10 20 30 40 50

Percent Total Cover

Interval (days)

0

5

10

15

20

25

30

35

40

Percent Sage Cover

Day

Night

Random

0

5

10

15

20

25

30

35

40

Percent Other Shrub Cover 

Percentage of sagebrush cover

Percentage of other shrub cover

Percentage of total shrub cover

A

B

C
27

Predator Surveys

Data from point surveys for ravens and raptors and transect surveys for badger activity will be 

compiled upon completion of the study. Predator abundance indices will be used as covariates in nest 

and brood survival models, allowing us to explore explained variation by these factors on vital rates of 

sage-grouse in the Virginia Mountains. We also will investigate the probability of nests depredated by 

each species of predator based on microhabitat characteristics. We have completed 99 surveys (badger, 

raven, and raptor) at sage-grouse nests. We have also completed over 500 random surveys of ravens and 

raptors throughout the study area (fig. 18). 

We installed cameras on three raven nests in the northern portion of the study site during 2009 

(n=2) and 2010 (n=1). In 2009, one of the nests was located in a natural cliff structure, while the other 

nest was positioned on an electrical transmission pole along Fish Springs Road. The following year, we 

reinstalled a camera on the nest positioned on the transmission pole. Personnel from Nevada Energy 

assisted us with the installation of the camera and digital video recorder (DVR) system. We collected 

approximately 2,500 hours of continuous videography on raven behaviors such as, chick feeding and 

adult feeding times, chick provisioning rates, and general activity during sage-grouse nesting periods. 

We obtained clear images of feeding (fig. 20), and we plan to quantify the amount of raven diet that 

consists of avian items (e.g., evidence of egg or chicks) throughout the sage-grouse nesting period. 
28

Figure 18. Distribution of point surveys for ravens and raptors across the study areas in the Virginia Mountains of 

Nevada during 2009 and 2010.
29

Figure 19. Raven nests monitored in 2009. A, An adult returns to feed nestlings at a nest located on a cliff ledge.

B, Adults exchanging food to pass to nestlings in a next located on a transmission pole.

Preliminary Data Interpretation

Growth and maintenance of sage-grouse populations in the Virginia Mountains study area 

appear limited and, based on preliminary findings, may be the result of relatively low nest survival. 

Range-wide averages of nest success (~ 50 percent; Schroeder and others, 1999) were substantially 

greater than estimates for the Virginia Mountains (13 percent). Although most studies across sagegrouse range reported apparent nest success rates, which overestimate nest survival (Kolada and others, 

2009; Coates and Delehanty, 2010), sage-grouse nest survival in the Virginia Mountains was 

substantially lower than in other areas of Nevada (Kolada and others, 2009; Coates and Delehanty, 

2010). Our limited sample size indicates that estimated brood success, in contrast to other populations 

within these study years, was relatively high compared to range-wide values (Schroeder and others,

1999). 

Increased wildfire cycles, coupled with increased seed production of cheatgrass, often result in 

invasive grass replacing intact sagebrush steppe across the landscape (Brooks and Pyke, 2001). At our 

study site, the majority of cheatgrass grew at relatively high elevations and sagebrush steppe was still 

relatively intact at lower elevations. Sage-grouse appeared to select nesting areas that were not within 

the lower elevation areas but instead selected nesting areas on greater slopes at relatively high 

elevations. Although sage-grouse appeared to avoid areas with cheatgrass, cover in these areas still 

largely consisted of this invasive plant species, which does not appear to provide the cover necessary for 

concealment for successful nesting. 

One explanation for why sage-grouse appear to nest at higher elevation sites with greater 

invasive grasses and much less shrub cover is site fidelity. Because of rapid invasion by cheatgrass 

based on increasing fire cycles, behavioral adjustment by sage-grouse may not correspond to the rapid 

changes in landscape vegetation. In other words, sage-grouse may have nested at the higher elevations 

prior to cheatgrass invasion and still maintain general nesting areas, even though habitat quality has 

A B
30

deteriorated. Another explanation is that higher elevation sites offer other important factors necessary 

for reproduction, such as proximity to upland springs for broods and greater distance from urban 

expansion at lower elevations. Sage-grouse may be avoiding nest predators often associated with 

anthropogenic structures (for example, roads and transmission lines). By positioning nests at relatively 

high elevations, females will be closer to open areas for brood-rearing. For example, we found females 

with broods appear to roost at night in relatively high elevation open areas without dense shrub cover, 

possibly where they can easily escape terrestrial predators by taking flight. However, we found during 

daylight hours, they moved their broods to areas with greater cover, which may provide more abundant 

food sources (for example, insects and forbs) and concealment. 

These hypotheses are not mutually exclusive. The benefits of predator avoidance while 

positioning nests in areas with access to upland springs for foraging and brood rearing following hatch 

may outweigh costs associated with loss of nesting cover at higher elevations. As we collect additional 

data, we will be able to assess the influence of the invasive annual grasses on habitat selection for nest 

sites by sage-grouse.

Raven populations appear relatively high throughout the study area compared to other reported 

numbers in Nevada sagebrush ecosystems (Coates and Delehanty, 2010). Ravens select powerlines for 

perching and nesting compared to other natural features (for example, cliff and tree) in the environment 

(Knight and Kawashima, 1993), and we observed ravens using anthropogenic structures at our study 

area. Raven abundance is negatively correlated with sage-grouse nest survival (Bui and others, 2010;

Coates and Delehanty, 2010). Therefore, based on these preliminary findings and other studies, 

development of anthropogenic infrastructure within the Spanish Flat area of the Virginia Mountains 

may further reduce sage-grouse nest survival rates, especially with lack of nesting vegetation cover

associated with increased cheatgrass invasion. 

With additional observations in the field, we will estimate nest, brood, and adult survival as a 

function of habitat factors and predator indices. We will also model movement across the landscape in 

relation to larger scale vegetation characteristics (for example, annual grass-cover types) and 

topography (for example, elevation and slope). Subsequent to energy development in this region, we 

will include energy-related covariates (for example, distance to transmission line) to inform movement 

and vital rate models. 

These reported data represent preliminary findings. Further study of nest predators, habitat, and 

energy development is required before conclusions can be made about the Virginia Mountain population

of sage-grouse. This type of study that focuses on measurements taken before and after energy 

development can provide critical information necessary to guide energy development in sagebrush 

ecosystems and, if needed, to mitigate potential negative effects to sage-grouse populations.

Acknowledgments

This report was prepared for the Nevada Department of Wildlife under agreement No. 09-52 

with the U.S. Geological Survey. Nevada Department of Wildlife and U.S. Fish and Wildlife Service 

provided funding to support this research. Sage-grouse were handled in accordance with the Animal 

Care and Use Committee, Western Ecological Research Center, with review from the University of 

California-Davis Wildlife Health Center.

We thank Chris Hampson with the Nevada Department of Wildlife for logistical support 

Rosemary Smith with the Idaho State University provided additional advice on study design and 

interpretation of results.

We thank Jonathan Dudko, Nick Kelly, Brian Halstead, and Pamela Gore with the U. S. 

Geological Survey for their substantial contributions in the field and office. 
31

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Publishing support provided by the U.S. Geological Survey Publishing 

Network, Lafayette, Sacramento, and Tacoma Publishing Service Centers

For more information concerning the research in this report, contact the 

 Director, Western Ecological Research Center

U.S. Geological Survey

3020 State University Dr.

Sacramento, California, 95819

http://werc.usgs.gov/
Coates and others—Preliminary Analysis of Greater Sage-Grouse Reproduction in the Virginia Mountains of Northwestern Nevada—Open File Report 2011-1182