Birds of Sonoran Desert Xeric Thorn Woodlands & Mojave Wilderness Integrity Assessment

2012 Progress Report

Chris McCreedy

PRBO Conservation Science 3820 Cypress Drive, No. 11 Petaluma, CA 94954

PRBO Contribution No. 1914

December 2012 TABLE OF CONTENTS

ACKNOWLEDGEMENTS 4 SUMMARY 5 BACKGROUND 6

CHAPTER 1: PATTERNS OF BIRD SPECIES COMPOSITION, RICHNESS, AND ABUNDANCE 8

1.1 METHODS

1.1.1 Point Count Censuses 8 1.1.2 California Natural Diversity Database 9 1.1.3 Breeding Status 9 1.1.4 Point Count Vegetation Assessments 10 1.1.5 Statistical Analyses and Definitions 10 1.1.6 Off-Highway Vehicle Use Assessments 11

1.2 RESULTS AND DISCUSSION

1.2.1 Species of Concern 12 1.2.2 Breeding Confirmations of Listed Species 13 Bell’s Vireo 13 Bendire’s Thrasher 13 Long-eared Owl 14 Gila Woodpecker 14 Lawrence’s Goldfinch 15 1.2.3 Species of Concern Documented at New Study Sites Initiated in 2012 15 Corn Spring 15 Palen-McCoy Wilderness 15 Mojave Wilderness Areas 16 1.2.4 Precipitation 17 1.2.5 Breeding Species Diversity, Richness, and Abundance 20 1.2.6 Migrant Species Diversity, Richness, and Abundance 24 1.2.7 Mojave Wilderness Surveys: A Lack of Data 25 1.2.8 Patterns of Off-Highway Vehicle Use 25

2

CHAPTER 2: MONITORING RECOMMENDATIONS 27

LITERATURE CITED 29

APPENDIX A Point Count Station Locations 31

APPENDIX B Plant Species Encountered During Habitat Assessments 43

APPENDIX C Bird Species Encountered and Breeding Statuses 45 San Bernardino County Sites 45 Riverside County Sites 48 New Riverside County Sites established in 2012 52 Imperial County Sites 54 Mojave Wilderness Points established in 2012 57

Cover photograph: Chris McCreedy

3 ACKNOWLEDGEMENTS

We are grateful for the financial and logistical support of the OHMVR Division of the California Department of Parks and Recreation, Arizona Bird Conservation Initiative, National Fish and Wildlife Foundation, BLM California and Arizona State Offices, the BLM El Centro, Lake Havasu, Palm Springs/South Coast, Needles, Tucson and Phoenix field offices, the Arizona Department of Game and Fish, and the staff, board and members of PRBO Conservation Science. Christine Bates, Daniel Steward, Jim Weigand, Thomas Bickauskas, and Francisco Mendoza (BLM) assisted with site selections. Alicia Rabas (BLM) assisted with plant identification, and provided housing for crew members surveying the Havasu NWR. Willow Dressel (BLM) piloted our crew to points in Topock Gorge. Charles Jason Tinant (BLM) assisted with nest searching, plant identification and vegetation assessments, and unfettered enthusiasm. Tom Johnson, Matt Sabatine, Len Warren (2012); Cassidy Grattan, Elizabeth Donadio, Emily Strelow, Andrew Tillinghast, Alex Wang, Paul Taillie, Alicia Young (2010);Colin Woolley, Rob Klotz, Caanan Cowles, Kim Kreitinger, Justin Hite (2009); Kelly Iknayan, Michelle Gibson, and Caroline Ailanathus (2008); Karl Bardon and Eileen Mueller (2007); Branden Wilson (2006); Jora Rehm-Lorber (2005); Stuart Johnson and Cali Crampton (University of Nevada-Reno) nest searched Chemehuevi nest plots (2004). Stella Moss, Ryan Carle, Colin Woolley, Sean Fitzgerald, and Kelly Iknayan (2008), John Felis, Courtenay Ray, Emily Morris, Scott Davies, Adrian Skok, and Tana Ellis (2007); Roy Churchwell, Tana Ellis, Alissa Fogg, and Justin Hite (2006); Justin Hite, Branden Wilson, Kristie Nelson, Dan Barton, Viola Toniolo (2005); Cliff Cordy, Alison Petersen, Mark Fogg (2004), Daniel Stewart (BLM) conducted point count surveys and vegetation assessments. Sacha Heath, Robert Meese, Geoffrey Geupel and Jim Weigand provided helpful comments on reports and feedback on study design and implementation. This is PRBO Contribution 1914.

4 SUMMARY

In 2012 PRBO Conservation Science completed a ninth consecutive season of bird and off-road vehicle (OHV) trail surveys in the xeric thorn woodlands of southeastern California’s Sonoran Desert. We surveyed thirteen core study sites (393 points, 2,777 hectares) in eastern San Bernardino, Riverside, and Imperial Counties and four new sites (89 points, 629 ha) in eastern Riverside County. These study sites are located on lands managed by the Needles, Lake Havasu City, Palm Springs, and El Centro BLM Field Offices and the Metropolitan Water District. In addition, we established and surveyed 195 Mojave Desert points (1,378 ha) to assess the condition of BLM-managed wilderness edges in northeastern San Bernardino County. In total, we conducted point count surveys at 677 points in 2012, covering roughly 4,784 hectares of Sonoran and Mojave Desert habitats (Figure 1).

Results include:

. Drought: The Lower Colorado River Valley/southeastern California region received, on average, less than 50% of its average winter precipitation in 2012. We have previously found positive correlation between winter precipitation and bird abundance and diversity (McCreedy 2011). Following this pattern, we found low bird abundance and diversity at many of our core study sites in 2012. Bird abundance at several sites approached lows following the severe droughts of 2006 and 2007.

. Spotty geographic distribution of winter precipitation: Regional winter rainfall patterns have historically been relatively simple to assess during our study. In general, the northern half of the Lower Colorado River Valley has tended to receive more winter precipitation than the valley’s southern half, and we have found winter drought condition to be relatively uniform throughout the entire region during each year of our work. Yet in 2012, we found small-scale but dramatic local differences in drought condition, even within single transects. Bird abundance and diversity estimates for 2012 would have been lower if not for these small pockets of isolated but higher rainfall.

. Patterns in OHV-use: As a whole, we found OHV trail density to increase across the entire study area from 2010, approaching trail density highs recorded in 2007. We recorded our greatest increases in trail density at Picacho Wash, Milpitas Wash, and Upper Chemehuevi Wash. As in previous years, we found evidence of illegal OHV use in signed areas to be common, though we recorded decreases in trail density both at the Riverside Mountains and Palo Verde Mountains Wilderness Areas from levels found in 2010.

. Discoveries at new Sonoran Desert sites in Riverside County: We found State Endangered Elf Owls and Gila Woodpeckers present at Corn Spring. This is the only remaining site in California where Elf Owls are still suspected to breed. We detected Curve-billed Thrashers and Pyrrhuloxia (only Riverside County’s fourth and third records, respectively) at the Palen-McCoy Wilderness. In spite of the season’s drought conditions, we established breeding statuses for a number of species, expanding known breeding distributions of California Species of Special Concern such as Crissal Thrasher and Lucy’s Warbler.

. New Mojave Desert sites in northeastern San Bernardino County: New sites included points in the Kingston Range, Mesquite, Stateline, and North Mesquite Mountains Wilderness areas. Drought conditions here were as severe (if not more so) as those experienced at Sonoran Desert sites. Bird abundance was very low, and we did not detect breeding for any species due to the dry conditions. However, we documented the presence of State Endangered Gilded Flickers at Mesquite Wilderness points. In addition, we noted 15 – 20 pairs of Le Conte’s Thrashers (a species of management concern) at Kingston, Mesquite, and North Mesquite Mountains sites.

5 BACKGROUND

PRBO Conservation Science has conducted nine years of bird and vegetation surveys using point count methodology across Sonoran Desert wash habitats in southeastern California, beginning in 2003. In addition, PRBO has completed five years of territory mapping, nest and vegetation monitoring, at Chemehuevi Wash in eastern San Bernardino County

The purpose of the Xeric Thorn Woodland and Mojave Wilderness Integrity Assessment studies are to:

 Provide the Bureau of Land Management (BLM) with baseline demographic data on both breeding and migrant bird populations that rely on Mojave Desert wilderness and on Sonoran Desert thorn woodlands

 Examine potential conflicts between off-highway vehicle (OHV) recreation and both breeding and migrant bird populations that rely on Mojave Desert wilderness and Sonoran Desert thorn woodlands.

 Provide the BLM with recommendations on best management practices in order to maintain and even increase breeding and migrant bird populations that rely on these habitats.

 Assess other (e.g. non-recreation) variables that may affect breeding and migrant bird populations in southeastern California, including feral burro overgrazing, Brown-headed Cowbird parasitism, and habitat associations.

 Provide management recommendations for BLM, California Department of Fish and Game, and other land management agencies.

 Further expand and refine these recommendations as we build sample sizes for more complex analyses.

Point count surveys in California began in the pilot season of 2003, when PRBO surveyed 144 points established by the BLM State Office and Needles Field Office. PRBO and the BLM added several hundred more points to the study in 2004, and additional points in 2005, 2007 and 2012 (in California and also in Arizona, via Arizona-based funding sources). In total, PRBO has conducted point count surveys at 1,409 stations at least twice during the 2003-2012 study, documenting bird presence, relative abundance, and species richness. These 1,409 stations were established across 46 sites in San Diego, Imperial, Riverside, San Bernardino, Yuma, La Paz, Mohave, Pinal, and Pima counties. We have completed intensive vegetation assessments at 436 core stations that we surveyed from 2003-2012.

In addition, PRBO found and monitored 982 nests for 30 species on high-recreation and low-recreation nest plots in Chemehuevi Wash from 2004-2008. Future analysis of these nests will allow PRBO to assess avian productivity across a continuous distribution of distances to both BLM-designated and unauthorized OHV trails. This will enable us to test for associations between OHV recreation and nesting success for multiple Sonoran Desert bird species.

PRBO has found that the thorn woodland habitats of the Lower Colorado River Valley host a much wider array of California endangered and sensitive species than previously known or documented. PRBO staff has documented several new breeding records for species of note across the study area. These include California State Endangered Gila Woodpeckers (2004) and Bell’s Vireos (2005), and California Species of Special Concern Bendire’s

6 Thrashers (2003), Long-eared Owls (2005), Lucy’s Warblers, and Crissal Thrashers (2003). These records have been used as important additions to the California Bird Species of Special Concern (Shuford and Gardali 2008) and The California Partners In Flight Desert Bird Conservation Plan (CalPIF 2009).

Figure 1. PRBO point count survey locations, 2012.

7 CHAPTER 1: PATTERNS OF BIRD SPECIES COMPOSITION, RICHNESS, AND ABUNDANCE

1.1 METHODS

1.1.1 Point Count Censuses

Xeric Thorn Woodland Sites

Using and expanding upon a grid of systematic random points generated by the BLM in 2002 (McCreedy 2004), we conducted censuses in xeric woodland habitats at 677 point count stations across Imperial, Riverside, and San Bernardino Counties (Figure 1) in 2012. Whenever possible, we established point count stations in wilderness areas close to primary washes, to provide control points with little or no off-highway vehicle use. All point count stations were placed within 50 m of xeric woodland. We present point count station names and UTM (NAD83) coordinates of new sites established in 2012 in Appendix A. Coordinates of sites established prior to 2012 can be found in previous reports (McCreedy 2011).

We conducted 5-minute Variable Circular Plot point counts following standards recommended by Ralph et al. (1993 and 1995) and Fancy and Sauer (2000). Distance to each detection was measured using a Leica Rangefinder LRF800, excluding detections greater than 150 m, and “flyovers”. We recorded all distances over 150 m as lumped ‘beyond 150 m’ detections. Each station was visited twice during the peak breeding season (between March 15 and May 15). We conducted first and second visits at least fifteen days apart, in order to capture varying detectability over time and among species.

All stations were surveyed by PRBO biologists trained by a PRBO staff biologist with several years of experience with the songs and calls of the birds in the area. To minimize observer bias, a different observer conducted each station visit. When feasible, stations were surveyed in opposite order between visits to minimize effects of time of day on detection rates. Censuses were conducted from within 30 minutes after local sunrise until approximately 4 hours later, and were not conducted in excessively windy or rainy conditions. Detections were categorized as song, visual, or call (drumming woodpeckers, flushing doves, and displaying hummingbirds were exceptions, and were categorized as ‘drumming’, ‘wing beats’, or ‘displaying’). We also recorded all observations of breeding behavior (e.g., nesting material carry) observed during counts and while walking between points.

We counted all Brown-headed Cowbirds (Molothrus ater), Eurasian Collared-doves (Streptopelia decaocto), Black-tailed Jackrabbits (Lepus californicus), and off-highway vehicles seen during census times as indices of presence. All bird species detected between stations, on return walks, and during vegetation assessments were recorded to more thoroughly document the bird species of our study areas.

Mojave Wilderness Sites

For Mojave Wilderness sites, we wished to compare wilderness edges along OHV routes with the interior wilderness of the Kingston Range, Mesquite, North Mesquite Mountains, and Stateline Wilderness Areas. For treatment points, we randomly selected starting points on wilderness boundaries in order to establish wilderness edge transects with points 250 m apart. We established treatment points to be within wilderness and 50 to 60 m from the road’s edge. We then paired treatment points with an equal number of interior wilderness control points. With treatment points as reference, we randomly selected a starting point in the wilderness interior with similar elevation, physiography, and vegetation cover. We used grid intersections of UTM NAD 83 coordinates ending in 000, 250, 500, and 750 for our pool of potential points. Once we had selected the starting control point, we randomly selected a grid direction (north, south, east, or west) for each subsequent control point, repeating

8 the process until we had generated enough control points to pair with nearby treatment points. All Mojave Wilderness points were surveyed using 5-minute Variable Circular Plot point counts, as described above.

1.1.2 California Natural Diversity Database

Detections and breeding observations of California Endangered, Threatened and Species of Special Concern were marked with a GPS unit and recorded for inclusion to the California Natural Diversity Database maintained by the California Department of Fish and Game (http://www.dfg.ca.gov/biogeodata/cnddb/).

1.1.3 Breeding Status

We assigned breeding statuses following Breeding Bird Atlas criteria (Corman and Wise-Gervais 2005) to all species detected at all sites during all visits from 2003-2012:

OBSERVED

CODE DESCRIPTION 0 Nonbreeder or migrant observed during breeding season, but not believed to be breeding; for species observed in unlikely breeding habitat or with no indication of breeding.

POSSIBLE

CODE DESCRIPTION 2 Species observed or identified by vocalization in suitable nesting habitat during its breeding season. Male observed singing on single occasion in potential breeding habitat, but also applicable to species without true songs (owls, woodpeckers, ravens, raptors). Not applicable to species singing on migration which have not been found to breed in study habitats.

PROBABLE

CODE DESCRIPTION 3 1) Pair observed in suitable habitat during its breeding season. 2) Permanent territory presumed through song at same location on at least two occasions seven or more days apart. 3) Courtship behavior or copulation. 4) Visiting probable nest site, but no further evidence obtained. This applies to cavity and aerie-nesters. 5) Agitated behavior or anxiety calls by the adult which signal a nest or young may be nearby. 6) Nest-building by specific species known to build roost nests, such as Verdin, wrens, and woodpeckers.

CONFIRMED

CODE DESCRIPTION 1 1) Bird seen carrying nesting material, applies for all species save Verdin, wrens, and woodpeckers, which may build roost nests. 2) Nest building observed at nest site. 3) Distraction display observed in defense of nest or young. This does not include agitated behavior, listed under Probable. 4) Used nest or eggshells found. 5) Recently fledged altricial young incapable of sustained flight, or downy precocial young restricted to natal area by dependence on adults. 6) Occupied nest found with eggs or young, or adult observed exiting and/or entering nest if nest contents cannot be seen. 7) Adults carrying food, excluding raptors, ravens, roadrunners, shrikes, and kingfishers. Adults of these species can carry food for some distance before eating it themselves. 8) Adults feeding recently fledged young. 9) Adult carrying fecal sac.

9 1.1.4 Point Count Vegetation Assessments

Using the relevé method described in Ralph et al. (1993), we estimated percent cover by height category for each species of plant equal to or greater than 0.50 m in height within a 50 m-radius circle that was centered on each point count station. We grouped plants under 0.50 m in height as “grasses”, “forbs”, or “woody” (with cacti as “woody”). Height categories were “herb” (0.01-0.49 m), “shrub” (0.5-4.9 m) and “tree” (>5 m).

We measured the width of the xeric woodland zone perpendicular to the wash at the station (xeric woodland width) using ArcView 3.2a (ESRI 2000) and digital orthophoto quadrangles (housed by the USGS at http://nationalmap.gov/viewer.html).

A key metric is the amount of ‘woodland’ cover, the summed percent cover of woodland vegetation, including: Blue and Foothills Palo Verde (Parkinsonia florida and P. microphylla), Ironwood (Olneya tesota), Honey Mesquite (Prosopis glandulosa var. torreyana), Desert Willow (Chilopsis linearis ssp. acuata), Smoketree (Psorothamnus spinosus), Catclaw Acacia (Senegalia greggii), and Tamarisk (Tamarix spp.). We determined elevations using 7.5’ USGS topographical maps. We used our vegetation measurements and guidance provided by Sawyer and Keeler-Wolf (1995) to assign dominant habitat series (habitat types) to each point. See Appendix B for a list of vegetation variables, and Appendix C for a list of plant species encountered during vegetation assessments.

1.1.5 Statistical Analysis and Definitions

Species Richness, Species Diversity, and Species Abundance

We calculated species diversity and species richness using two bird population datasets: 1) all species detected (migrants and breeders) and 2) the set of 45 breeding species currently known to breed at our study sites. We did not include flyover detections in analyses.

Species Diversity

We calculated species diversity for each point count station and each wash grid using all detections within 100 m, summed over two visits. We used the transformed Shannon-Wiener index of biological diversity, denoted N1 (MacArthur 1965, Krebs 1989). This index of diversity is usually highly correlated with bird species richness, but also takes the number of individuals of each species into account. Higher scores on the Shannon-Wiener index indicate higher species richness and more balanced numbers of individuals of each species added. Expressed mathematically:

H' iS N1 = e and H' ( pi)(ln pi)(-1) i1

Where S = total species richness and pi is the proportion of the total numbers of individuals for each species (Nur et al. 1999).

Species richness

We calculated the number of species for each point count station and each wash grid, using all detections within 100 m, summed over two visits.

Abundance by Species

We calculated the mean number of individuals detected, averaged over the entire wash grid, then averaged over two visits, using all detections within 100 m (but see below). Because few species are 100%

10 detectable, such calculations may underestimate absolute density. Therefore results should be considered minimum estimates of relative abundance.

Species diversity, richness, and relative abundance summaries were conducted using Point Count 2.8 (Ballard 2005).

1.1.6 Off-Highway Vehicle Use Assessments

We annually survey all point count stations for off-highway vehicle use, recording trail density and distance to trail. Distance to trail was measured in the field if a trail was within 100 m of the point. Otherwise, distance to trail was measured with Google Earth (2012).

Trail density is the linear length of OHV trails found within 50 m of each point count station. A “trail” has the approximate width of a Jeep or dune buggy (Brooks and Lair 2009). Thus, the amount of area disturbed by trails within the 50 m-radius circle can be calculated by multiplying the trail density value by 2 m (the approximate width of a vehicle). Occasionally, trails two or three-Jeeps wide were encountered. While measuring trail density, surveyors doubled or tripled these wide trails’ lengths within the 50 m-radius circle to account for this, depending on the trail width.

Trail densities were recorded for BLM-designated trails (those signed or present on route maps provided by the BLM) and “unauthorized” trails. Unauthorized trails included any recently-created trails outside of BLM- designated trails.

Great care was taken to count only trails that were clearly recent in origin, using signs such as damaged vegetation. As desert wash soils are generally sandy in structure, few density assessments included rocky desert pavement substrates that can hold trail signs for years or even decades. If trails in desert pavement settings were encountered, great care was again taken to ensure that the trail was only counted when signs of recent use were apparent. Trail density data was gathered in a geographically random fashion across the study area throughout the season, avoiding potential bias created by last rainfall and the timing of assessments.

11 1.2 RESULTS AND DISCUSSION

1.2.1 SPECIES OF CONCERN

We detected 41 species of management concern at CA study sites in 2003-2012.

Table 1. Special status species detected during, before, or after standard censuses at study sites, 2003-2012. Breeding species in bold type. See Appendix D for breeding status by site. PIF BLM Watch Audubon Common Name SE ST CSSC USFWS BCC Sensitive List Watch List Least Bittern x American White Pelican First Golden Eagle x BLMS Northern Harrier Third Swainson’s Hawk ST BLMS x Elf Owl SE BLMS x yellow Long-eared Owl Third Vaux’s Swift Second White-throated Swift x yellow Costa's Hummingbird x x yellow Calliope Hummingbird x yellow Rufus Hummingbird x yellow Gila Woodpecker SE x BLMS Williamson’s Sapsucker yellow Gilded Flicker SE BLMS Olive-sided Flycatcher Second x yellow Willow Flycatcher SE x Vermilion Flycatcher Second Loggerhead Shrike Second x Bell's Vireo SE x BLMS X red Gray Vireo Second BLMS yellow Oak Titmouse X yellow Wrentit X yellow Bank Swallow ST BLMS Bendire's Thrasher Third x BLMS x red California Thrasher x yellow Crissal Thrasher Third Le Conte’s Thrasher x x yellow Virginia's Warbler x yellow Lucy's Warbler Third x BLMS x yellow Yellow Warbler Second Hermit Warbler x yellow Yellow-breasted Chat Third Abert's Towhee x yellow Brewer's Sparrow x yellow Black-chinned Sparrow x x red

12 Sage Sparrow yellow Grasshopper Sparrow Second X Lark Sparrow Yellow-headed Blackbird Third Lawrence’s Goldfinch x x yellow SE = California State Endangered; ST=California State Threatened http://www.dfg.ca.gov/biogeodata/cnddb/pdfs/TEAnimals.pdf CSSC = California Species of Concern List 2003, and 1st, 2nd, or 3rd priority http://www.prbo.org/cms/docs/terre/List_17_Oct_2003.pdf USFWS BCC = USFWS Birds of Conservation Concern 2008 list http://www.fws.gov/migratorybirds/NewReportsPublications/SpecialTopics/BCC2008/BCC2008.pdf BLM Designate Sensitive Species http://www.blm.gov/pgdata/etc/medialib/blm/ca/pdf/pa/wildlife.Par.13499.File.dat/BLM%20Sensitive%20Animal%20Update%20SEP2006.pdf PIF WL = Partners In Flight Watch List http://www.partnersinflight.org/watchlistneeds/Research%20Crosswalk%20Taxon.htm Audubon WL = Audubon 2007 Watch List http://birds.audubon.org/2007-audubon-watchlist

1.2.2 BREEDING CONFIRMATIONS OF LISTED SPECIES

We confirmed breeding for several species listed as threatened or endangered in California across our Lower Colorado River Valley study sites. Several of our finds represent new records for these species not previously documented to breed in these habitats, and/or in southeastern California. These records underscore the value of these desert wash systems as vital habitat for a variety of bird species with geographically restricted or threatened populations. Bell’s Vireo, Bendire’s Thrasher, and Long-eared Owl breeding records all occurred in areas with zero to very infrequent OHV-use (PRBO data) – despite a trend for highest breeding bird diversity to occur in areas with high OHV use.

Bell’s Vireo

On April 18, 2005, a PRBO biologist located an active Bell’s Vireo nest in upper Chemehuevi Wash. Bell’s Vireos are a California State Endangered Species that had not been previously found to utilize palo verde woodland as nesting habitat in California (records at the Western Foundation of Vertebrate Zoology (WFVZ), California Natural Diversity Database (CNDDB), Guy McCaskie, John Green and Sandy Koonce, personal communications). This nest was constructed in a Blue Palo Verde at a distance of over 15 km from the Colorado River. The nest fledged three young on May 17, 2005. The nest was located in a section of Chemehuevi Wash with zero to minimal signs of OHV-use. We have not found territorial Bell’s Vireos at any study sites since 2005.

Bendire’s Thrasher

PRBO located Bendire’s Thrasher nests or paired individuals in upper Chemehuevi Wash in each of the first eight seasons of our study (2003-2010). 2012 was the first season in which we did not find paired individuals on the Chemehuevi Wash, though we did observe single individuals and it is possible that breeding occurred in 2012. We have located ten nests in total (one in 2003, three in 2005, four in 2006, two in 2007, and one in 2008 and 2009). Bendire’s Thrasher is a California Bird Species of Special Concern, a Partners In Flight Watch List species of First Priority, and a BLM California Sensitive Species. This species’ status in California (and particularly in California’s portion of the Sonoran Desert) remains largely unknown (Sterling 2008, England and Laudenslayer 1989). Prior to our discovery of a nesting pair in 2003, this species has not been previously found to nest in Chemehuevi Wash (England and Laudenslayer 1989, though one egg-set housed at the WFVZ was suggestively

13 taken at “33 miles southeast of Needles”). Only seven Bendire’s Thrasher nests had been found during incubation in California since records began in the late nineteenth century (England and Laudenslayer 1989, records at the WFVZ). In this study, seven of ten nests were located during incubation. Aside from a core area in the vicinity of the Mojave National Preserve (Sterling 2008), Chemehuevi Wash appears to be the only known location in California with a perennial Bendire’s Thrasher population.

All ten Bendire’s Thrasher nests were located on portions of Chemehuevi Wash with zero to minimal signs of OHV-use. We have recorded repeated instances of singing Bendire’s Thrashers at the Riverside Mountains Wilderness, but our biologists have felt that these males were likely unmated.

Long-eared Owl

In 2005, PRBO located four active Long-eared Owl nests, one in Milpitas Wash, one in the Riverside Mountains Wilderness, one in Vidal Wash, and one in Chemehuevi Wash. Long-eared Owl is a California Species of Special Concern not previously known to nest in native xeric woodland habitat in California (records at the WFVZ, Rosenberg et al. 1991, Guy McCaskie, John Green, and Sandy Koonce, personal communications). Only one previous breeding record exists for the region, a fledgling sighted on the Colorado River in Topock Marsh (Rosenberg et al. 1991). The Arizona Breeding Bird Atlas reports one breeding confirmation on the Arizona side of the Colorado River, but outside the Colorado River Valley, at the Kofa NWR (Corman and Wise-Gervais 2005). Elsewhere in California’s portion of the Sonoran Desert, a handful of records exist in non-native tamarisk habitats west of the Salton Sea (Massey 1998, James Weigand, personal communication).

Large, old-growth xeric woodland was a requisite for Long-eared Owl nesting habitat at our study sites. Two nests were constructed in Blue Palo Verde trees averaging 6.25 m in height, and two in Ironwood trees averaging 9.75 m in height. All four Long-eared Owl nests were located in areas with zero to minimal signs of OHV- use.

Pairs returned to breed at identical locations at Riverside Mountains Wilderness and Vidal Wash in 2006, but not in Chemehuevi or Milpitas Wash. We have not documented nesting Long-eared Owls at any study sites since 2006.

Gila Woodpecker

PRBO has documented 4-5 pairs of Gila Woodpeckers of Milpitas Wash each season since their discovery in 2004. The Milpitas Wash population represents an important component of the California population, which has been estimated at only 200 individuals (detailed in McCreedy et al. 2005). All ten located cavities were excavated in old-growth Blue Palo Verde trees averaging 7.2 m (6.1, 8.3) in height and 45.8 cm diameter at ground height (40.3, 51.3). Territories were large in extent, occasionally reaching over 1 km in diameter.

We found that Gila Woodpecker nest trees were occasionally in sections in Milpitas Wash with extensive signs of OHV-use. Sample sizes are too low to describe OHV-use effects on Gila Woodpecker territory density. However, the large, contiguous old-growth woodland found on the Milpitas Wash is most-likely responsible for the presence of this State of California Endangered Species.

Gila Woodpeckers continued at Milpitas Wash through 2012, though anecdotal evidence (the wash was not thoroughly canvassed) may place the population at now only 3 pairs.

14 Lawrence’s Goldfinch

A PRBO biologist located an active Lawrence’s Goldfinch nest at Salt Creek on March 26, 2005. The nest housed five eggs and was constructed in a 4.4 m-tall lone Athel tamarisk (Tamarix aphylla) amidst Blue Palo Verde and Ironwood. Lawrence’s Goldfinches are a USFWS species of management concern, and are on the PIF and Audubon Watch Lists. They have not been previously found to nest in the region (Patten et al. 2003, records at the WFVZ, Guy McCaskie, John Green, and Sandy Koonce personal communications), though riparian nesting at the Colorado River near Blythe was noted in 1978 (Rosenberg et al. 1991). This nest was located on a section of Salt Creek with high OHV-use. We have not found Lawrence’s Goldfinches nesting at study sites since 2005.

1.2.3 SPECIES OF CONCERN DOCUMENTED AT NEW STUDY SITES INITIATED IN 2012

Corn Spring

On April 4, 2012 a PRBO biologist documented a calling Elf Owl near the Corn Spring campground. This was apparently the first sighting of 2012, as other birdwatchers present earlier in the week did not report the owl’s presence. The California Bird Records Committee ascribed an audio recording PRBO sent to the CBRC as record number 2012-045. PRBO biologists again noted Elf Owl vocalizations during our second visit to Corn Spring on April 30.

Elf Owls have been detected periodically at Corn Spring since 2010, and they were present throughout the 2012 breeding season (Curtis Marantz, personal communication). Though it is believed that a pair (and not a lone individual) inhabits the old stand of palms at the Corn Spring Campground, to our knowledge successful breeding has not been confirmed in 2010, 2011, or 2012. If Elf Owls are indeed breeding at Corn Spring, they may represent the last pair of breeding Elf Owls (a State Endangered Species) in California.

PRBO biologists also found at least two Gila Woodpeckers present at Corn Spring on May 1. This may be the first Gila Woodpecker observation at Corn Spring in 2012, as they were not present in previous reports or during our first point count surveys in early April. However, they have been reported through the fall of 2012 (www.ebird.org). The Corn Spring campground’s palm trees provide large boles for potential nesting substrate for the Gila Woodpeckers as well, and resident Gila Woodpeckers would in turn excavate additional cavities for potential use by Elf Owls. Corn Spring would represent the northwestern-most breeding location in the Gila Woodpecker’s distribution if they did in fact remain to breed. Closest known populations are in Brawley and at Milpitas Wash (above).

Palen-McCoy Wilderness

On April 19 a PRBO biologist found a Curve-billed Thrasher near a point count station in the Palen-McCoy Wilderness. The bird was originally thought to be a Crissal Thrasher, and its guarded behavior led the biologist to return to the location on April 20 in hope of confirming breeding. The bird was present in the same location on April 20, at which point the individual was identified as a Curve-billed Thrasher. Though common in eastern and central Arizona, Curve-billed Thrashers are remarkably rare in California, and to date they had never been detected at our California sites. The thrasher was traveling with a second individual. We never confirmed the identity of the second thrasher beyond genus (Toxostoma, the genus of Crissal, Curve-billed, Le Conte’s, and Bendire’s Thrashers); our sense is that there was a reasonable probability that we had found a pair of Curve-billed Thrashers.

We returned for a third visit on April 27. Again, the birds were present (600 m north of the original sighting), but we were unable to detect nesting behavior. Unfortunately, due to the season’s extreme drought we did not observe nesting for any thrashers at all study sites, as this could have represented the first confirmed

15 Curve-billed Thrasher nesting in California. Nonetheless, this individual (CBRC Record Number 2012-051) represents only the fourth Riverside County record and 29th California record (California Bird Records Committee data) overall.

On April 28, a PRBO biologist documented a Pyrrhuloxia prior to their point count, on the northern edge of the Palen-McCoy Wilderness and near Arlington Mine Road. This individual was moving rapidly upwash and to the north, outside of the wilderness area. Similar in distribution to Curve-billed Thrashers, Pyrrhuloxia are common in central Arizona but are rarely observed in California. This observation (CBRC Record Number 2012- 061) represented only the third Pyrrhuloxia record in Riverside County and 27th in California (California Bird Records Committee data).

The valley that extends between the Palen and McCoy Mountains is notable in its north-south axis, as most valleys of southeastern California are oriented eastward toward the Colorado River. This may help to explain why transients such as the Curve-billed Thrasher and Pyrrhuloxia were found at this location in only first year of our surveys there.

Mojave Wilderness Areas

PRBO biologists documented single State Endangered Gilded Flickers during surveys in the Mesquite Wilderness on May 10 and 11. A small population of Gilded Flickers is known to persist south of our study sites, in the Mojave National Preserve, and it is unknown whether detected individual(s) were simply Mojave NP birds wandering prior to their nesting season or indeed resident to our study sites.

We detected Le Conte’s Thrashers on several transects in the Mesquite, Kingston Range, and North Mesquite Mountains Wilderness areas. While this species of management concern is to be expected in these Joshua tree and yucca habitats, we found an estimated 15 to 20 pairs during our point count surveys this spring.

Extreme drought conditions resulted in prolonged delay in nest initiation in 2012, and we did not observe nesting behavior for any species on our Mojave Wilderness transects. However, Le Conte’s Thrashers and Gilded Flickers are resident species, and further years of survey may very well provide confirmed breeding for both of these sensitive species at Mojave Wilderness study sites.

16 1.2.4 PRECIPITATION

We have found correlations between winter precipitation and bird abundance and richness during previous years of our study (McCreedy 2011). Estimates of bird abundance and richness can vary greatly between wet and dry years in the Sonoran Desert, and it is of critical importance to consider prevailing climatic conditions when considering variation in bird abundance and diversity between years.

We define winter rainfall as the accumulated precipitation between November 1 and April 30. This 6- month period is the ‘wet’ season in the Sonoran Desert, and rainfall during this period is responsible for much of the variation in primary production observed each subsequent spring. Thus when describing ‘2012 winter rainfall’, we are referencing precipitation accumulation between November 1, 2011 and April 30, 2012.

The great majority of the region received far less than its average winter rainfall in 2012 (Figure 2). Nineteen weather stations located across the study area reported Nov 1 – Apr 30 rainfall totals ranging from 1.05” (Eagle Mountain, between Joshua Tree National Park and Desert Center in Riverside County) to 2.56” in Lake Havasu City, Arizona (National Climatic Data Center data).

Figure 2. Rainfall amounts (expressed as percent of normal) from October 13, 2011 through April 13, 2012 in Arizona and southeastern California. Red areas received less than 25% normal precipitation during this period, and orange areas less than 50%. Graphic provided by the National Weather Service’s Advanced Hydrologic Prediction Service (http://water.weather.gov/precip/ ).

17 The winter of 2012 was the third-driest winter during the nine years of the study, topped only by record dry winters of 2006 and 2007 (Table 1). We have used the Chemehuevi Wash as a representative site in order report precipitation in Table 1. However, it is important to note that while winter rainfall at the Chemehuevi Wash was slightly above normal in 2011, the winter of 2011 was much drier than normal across the southern half of the Lower Colorado River Valley. In addition, summer ‘monsoonal’ rainfall was far below normal in both 2010 and 2011 for the region. As a result, much of the study area has experienced abnormally dry conditions since the summer of 2010 (USDA Drought Monitor Archive at http://droughtmonitor.unl.edu/archive.html).

Table 1. Winter precipitation (inches) at Chemehuevi Wash, CA (2004- 2012). Winter precipitation equals total rainfall from Nov 1 the previous calendar year to Apr 30 of the listed calendar year. Normal winter precipitation is 2.55 inches (National Climatic Data Center). Year Winter Precipitation (inches) 2004 1.92 2005 8.97 2006 0.53 2007 0.64 2008 2.75 2009 3.59 2010 4.63 2011 3.01 2012 1.89

While 2012 was very dry, it is notable that there were isolated pockets of green, wet conditions across the study area. Higher rainfall that fell in these localized areas was generally missed by well-spaced weather stations in the region. Yet we found the differences between these isolated wet areas and the region’s dry general condition to be very dramatic.

For example, drought caused Phainopeplas to abandon their territories at many other sites in the study area without laying clutches, yet by backdating fledglings, we found that Phainopeplas had initiated nests by mid- February at Corn Spring and in the Little Picacho Wilderness. Due to heavy rain in the Palen Mountains and essentially no rain in the adjacent McCoy Mountains, the western half of our Palen-McCoy Wilderness transect was in flower and the eastern half brown. In a similar vein, the northern channel of the Upper Chemehuevi Wash (fed by runoff from the Chemehuevi Mountains) was lined with flowering blue palo verdes, while the southern channel (fed by the Whipple Mountains) was flowerless. A small pocket of wet conditions on the eastern third of the North of Palen-McCoy Wilderness transect produced one of the biggest migrant fallouts we observed during the second half of April. Less than ten miles away, starkly dry conditions on the McCoy Wash produced nearly the lowest number of bird detections we have recorded in eight years of surveys. Though necessarily an anecdotal observation, we had not witnessed such highly localized winter rainfall patterns in the region before 2012. Estimates of bird abundance and diversity would have been much lower if not for these small areas of green amidst the drought.

We created vegetation condition maps over the course of the season in an attempt to record the localized nature of the winter’s rainfall patterns, and they are reproduced in Figure 3. Using cues of vegetation condition such as foliage condition on ironwoods, palo verdes, and creosotes, flowering condition of trees and of annuals, and the height of annual, climbing lianas such as Brandagea we defined and mapped 5 drought condition levels for

18 study sites and while driving between sites in an effort to add perspective to the estimates of bird abundance and species richness that we have reported.

Figure 3. Observed vegetation condition across the study area in March and April 2012. Condition classes range from [1] relatively very dry to [5] relatively very wet and are defined as follows: 1] No annual vegetation, creosote leaves completely brown and often have been dropped. No leaves on palo verdes, no flowers on trees, catclaw acacia not flushed by the end of second point count visits; 2] creosote leaves still mostly brown but some green faintly visible, a rare flowers making an appearance on palo verde; 3] creosotes a little more green, catclaw acacia seems to be flushing more or less on time though leaves look stressed, a few more flowers on palo verdes, rare, small piles of Brandagea seen though not climbing yet. Annual wildflowers occasionally found though they are very small in height; 4] Creosote leaves fairly green now, palo verdes often with heavy crops of flowers, annuals more common; 5] Essentially all palo verdes in flower in April, ironwood leaves a deep green, creosote leaves green, Brandagea observed to be climbing on woody vegetation. Study sites marked by red dots that correspond to labels provided in Figure 1. Mapped vegetation classes may not necessarily match well with precipitation maps of the region. Rather, this map is provided to illustrate relative differences in primary production across the study area in the spring of 2012. As such, Red Cloud Wash (P), Corn Spring (Q), Picacho Wash (U), and the Little Picacho Wilderness (V) were the ‘greenest’ sites surveyed in 2012. McCoy Wash (N), the eastern half of Chuckwalla Thicket (R), and Riverside Mountains Wilderness (K) were the driest.

19 1.2.5 BREEDING SPECIES DIVERSITY, RICHNESS, AND ABUNDANCE

Table 2 displays breeding species diversity, richness, and abundance estimates for study sites in 2012. We have listed sites together in order to provide the reader with a site comparison for the region.

Table 2. 2012 breeding species diversity, richness and relative abundance by-point, as well by-hectare abundance at Sonoran Desert xeric thorn woodland sites and at Mojave Desert wilderness sites. Indices are for breeding species detected within 100 m during 5-minute VCP point counts, summed over 2 visits. Total SW Species Total Abundance Station n SW SD Richness Richness SD Abundance Abundance SD Per ha Xeric Thorn Woodland Sites Chemehuevi Wash 41 3.69 2.6 4.12 3.2 7.92 7.4 2.522 Chuckwalla Thicket 11 2.15 1.6 2.36 1.9 4.45 4.1 1.417 Copper Basin 22 3.30 1.6 3.68 1.9 6.91 5.2 2.201 Corn Spring 30 4.54 2.1 5.00 2.3 8.30 3.9 2.643 Little Picacho Wilderness 12 5.24 2.0 5.75 2.2 9.42 4.8 3.000 McCoy Wash 30 3.24 1.3 3.53 1.5 7.63 4.0 2.430 Milpitas Wash 90 4.08 1.5 4.63 1.8 8.37 4.1 2.666 North of Palen-McCoy Wilderness 24 3.75 1.6 4.25 2.0 8.25 4.6 2.627 Palen-McCoy Wilderness 24 3.44 1.0 3.88 1.2 7.63 2.5 2.430 Palo Verde Mountains Wilderness 21 2.46 1.2 2.57 1.3 3.76 2.3 1.197 Picacho Wash 14 5.19 1.3 6.00 1.7 11.86 5.1 3.777 Red Cloud Wash 24 5.21 1.5 5.88 1.8 12.25 4.9 3.901 Riverside Mountains Wilderness 27 1.17 0.8 1.19 0.8 1.92 1.6 0.611 Salt Creek 24 4.33 1.2 5.17 1.6 11.25 5.1 3.583 Upper Chemehuevi Wash 41 4.41 1.2 5.05 1.5 11.05 5.3 3.519 Vidal Wash 28 3.66 1.0 3.96 1.1 6.25 2.0 1.990 Whipple Mountains Wilderness 19 3.97 1.6 4.58 2.0 9.47 7.8 3.016 Mojave Wilderness Area Sites Eastern Mesquite Wilderness 45 0.72 0.8 0.73 0.8 0.98 1.1 0.312 Kingston Range Wilderness 48 1.41 1.0 1.44 1.0 1.90 1.4 0.605 Mesquite Wilderness 48 1.57 1.1 1.69 1.2 2.81 2.5 0.895 North Mesquite Wilderness 24 0.99 1.0 1.04 1.1 1.67 2.0 0.532 Stateline Wilderness 30 0.43 0.7 0.43 0.7 0.43 0.7 0.137

20 Figures 4a-4d depict changes in breeding species diversity over the course of the nine-year study. Sites are grouped by geographic location and number of years surveyed for more useful comparison. 2012 breeding species diversity estimates decreased from those of eight of twelve sites surveyed in 2010, and remained the same at another. Each of the three sites that showed increases in 2012 (Little Picacho Wilderness, Picacho Wash, and Whipple Mountains Wilderness) apparently received localized rainfall and were in wetter condition relative to the majority of the study area (Figure 3). McCoy Wash, Riverside Mountains Wilderness, and the Copper Basin have shown decreases in breeding species diversity over the course of the study, while species diversity at Picacho Wash and Little Picacho Wilderness has trended upward slightly.

We have conducted the study over a range of wet and dry conditions, with three wet years (2005, 2009 and 2010), three dry years (2006, 2007, and 2012), and two average years (2004, 2008). Figures 4a-4d illustrate the range of species diversity values that might be expected over a wide range of climatic conditions at southeastern California study sites.

6.00 Xeric Thorn Woodland: Breeding Species Diversity

5.00 Vidal Wash

4.00 Riverside Mountains Wilderness McCoy Wash 3.00

Milpitas Wash W W Diversit Index

- Chemehuevi Wash S 2.00 Upper Chemehuevi Wash

1.00

0.00 2004 2005 2006 2007 2008 2009 2010 2012 Year Figure 4a. Breeding species diversity (measured by Shannon-Wiener Diversity Index) at core xeric thorn woodland study sites, 2004-2012.

21 6.00 Xeric Thorn Woodland: Breeding Species Diversity

5.00

4.00 Copper Basin 3.00

Whipple Mountains Wilderness W W Diversity Index

- 2.00 S Palo Verde Mountains Wilderness 1.00

0.00 2004 2005 2006 2007 2008 2010 2012 Year

Figure 4b. Breeding species diversity (measured by Shannon-Wiener Diversity Index) at higher-elevation, xeric thorn woodland study sites, 2004-2012.

6.00 Xeric Thorn Woodland: Breeding Species Diversity

5.00

4.00

3.00 Red Cloud Wash

Salt Creek W W Diversity Index

- 2.00 S

1.00

0.00 2005 2008 2009 2010 2012 Year

Figure 4c. Breeding species diversity (measured by Shannon-Wiener Diversity Index) at Chuckwalla Bench xeric thorn woodland study sites, 2005-2012.

22 6.00 Xeric Thorn Woodland: Breeding Species Diversity

5.00

4.00

3.00 Picacho Wash

Little Picacho Wilderness W W Diversity Index

- 2.00 S

1.00

0.00 2004 2005 2006 2007 2008 2010 2012 Year

Figure 4d. Breeding species diversity (measured by Shannon-Wiener Diversity Index) at southern xeric thorn woodland study sites, 2004-2012.

23 1.2.6 MIGRANT SPECIES DIVERSITY, RICHNESS, AND ABUNDANCE

Table 3 lists migrant species diversity, richness, and abundance estimates for all sites surveyed in 2012. The term ‘migrant’ connotes only non-breeders detected on point count surveys. Species that migrate to study sites to subsequently breed (e.g. Lucy’s Warblers) are considered ‘breeders’. Sites with highest vegetation condition (Little Picacho Wilderness, Corn Spring, Picacho Wash, Figure 3) tended to hold highest migrant abundance and richness.

Table 3. 2012 migrant species diversity, richness and relative abundance by-point, as well by-hectare abundance at Sonoran Desert xeric thorn woodland sites and at Mojave Desert wilderness sites. Indices are for migrant (nonbreeding) species detected within 100 m during 5- minute VCP point counts, summed over 2 visits. Total sw Species Richness Total Abundance abundance per Station n sw SD richness SD abundance SD ha Xeric Thorn Woodland Sites Chemehuevi Wash 41 1.74 1.6 1.90 1.9 3.41 3.9 1.086 Chuckwalla Thicket 11 1.36 1.1 1.55 1.4 2.45 2.8 0.780 Copper Basin 22 1.31 1.1 1.36 1.1 1.77 1.8 0.564 Corn Spring 30 2.22 1.3 2.47 1.5 4.90 5.2 1.561 Little Picacho Wilderness 12 3.62 1.4 4.00 1.7 5.75 3.0 1.831 McCoy Wash 30 0.99 1.1 1.07 1.3 2.20 2.8 0.701 Milpitas Wash 90 1.97 1.4 2.13 1.6 3.53 3.7 1.124 North of Palen-McCoy Wilderness 24 1.64 1.8 1.79 2.0 2.92 3.7 0.930 Palen-McCoy Wilderness 24 1.38 1.1 1.46 1.3 2.21 3.0 0.704 Palo Verde Mountains Wilderness 21 0.52 0.7 0.53 0.7 0.57 0.9 0.182 Picacho Wash 14 1.88 1.0 2.07 1.1 4.36 3.8 1.389 Red Cloud Wash 24 1.29 1.2 1.38 1.3 2.67 3.1 0.850 Riverside Mountains Wilderness 27 0.40 0.7 0.41 0.7 0.93 1.8 0.296 Salt Creek 24 1.74 1.3 1.88 1.4 3.38 3.7 1.076 Upper Chemehuevi Wash 41 1.81 1.3 1.93 1.3 2.90 3.1 0.924 Vidal Wash 28 1.40 1.1 1.57 1.5 3.21 4.0 1.022 Whipple Mountains Wilderness 19 1.16 0.9 1.22 1.0 2.32 2.3 0.739 Mojave Wilderness Sites Eastern Mesquite Wilderness 48 0.00 0.0 0.00 0.0 0.00 0.0 0.000 Kingston Range Wilderness 48 0.21 0.4 0.21 0.4 0.48 1.3 0.153 Mesquite Wilderness 48 0.38 0.5 0.38 0.5 0.54 0.8 0.172 North Mesquite Wilderness 24 0.17 0.4 0.17 0.4 0.29 0.9 0.092 Stateline Wilderness 30 0.27 0.4 0.27 0.4 0.33 0.7 0.105

24 1.2.7 MOJAVE WILDERNESS SURVEYS: A LACK OF DATA

Mojave Wilderness area points were established with the objective of producing a baseline for future comparison of wilderness interior (control) and wilderness edge (treatment) points. However, the 2012 season alone is likely an insufficient baseline, due to severe drought conditions in northeastern San Bernardino County during the spring (Drought Monitor 2012, http://droughtmonitor.unl.edu/archive.html). We have already demonstrated through several years of surveys that bird diversity, richness and abundance can vary greatly between years in response to drought conditions. Lack of nesting and very low detection rates (Tables 2 and 3) are signs that 2012 was an atypical spring, and we recommend additional surveys at Mojave Wilderness points in order to better gauge the full suite of conditions experienced by birds of these habitats.

1.2.8 PATTERNS OF OFF-HIGHWAY VEHICLE USE

Trail density measurements are presented in Table 4. As in previous years, we frequently found signs of recent OHV-use in signed wilderness areas where OHV-use is illegal. However trail density decreased dramatically from 2010 to 2012 at Riverside Mountains Wilderness and Palo Verde Mountains Wilderness, where we had found fairly high trail density in 2010.

Notable increases in trail density occurred at 1] the Upper Chemehuevi Wash, 2] the McCoy Wash east of Inca, 3] Milpitas Wash and 4] Red Cloud Wash.

We found widespread establishment of unauthorized trails on the Upper Chemehuevi Wash west of the Needles-Parker trail. The majority of these trails appeared to be associated with the recent establishment of a homestead near the wash. PRBO biologists have notified the BLM Needles FO to the spread of unauthorized trails in the Upper Chemehuevi Wash corridor, as the Upper Chemehuevi holds nesting populations of Bendire’s Thrashers, Crissal Thrashers, Le Conte’s Thrashers, Lucy’s Warblers, and Loggerhead Shrikes. It annually holds among the highest bird richness and abundance values found in the entire study area, it is the only location where we have documented nesting Bell’s Vireos and Bendire’s Thrashers, and it is one of only three locations where we have documented nesting Long-eared Owls.

Trail density notably increased at the McCoy Wash, particularly at eastern points east of the ghost town of Inca. We found recent evidence of an exceptionally large bonfire with related motorcycle and quad tracks throughout the wash corridor. Wildfire is probably the greatest threat to the integrity of thorn woodland habitats, and we have fortunately rarely encountered signs of bonfires (we generally find burn pits only at Picacho Wash) such as on McCoy Wash in 2012.

Trail density also greatly increased at Milpitas Wash. This may stem from changes in management patterns, as PRBO biologists did not report signed trails on the Milpitas before 2012. Milpitas Wash also typically holds high abundance and richness values, and it remains the only wash in which we have confirmed breeding for State Endangered Gila Woodpeckers.

Finally, we found trail density to increase significantly at Red Cloud Wash from 2010 levels. While we do not know the Red Cloud Wash’s management history, it was clear the BLM was making an effort to limit OHV-use on the Red Cloud Wash. We found signs forbidding use and recently-placed vertical mulching. However, we also met campers that were apparently staying long-term on the wash during our surveys, and we observed recently- created trails that bypassed a teetering no-use sign near our point 13, running farther east up the wash.

It is important to note that trail density estimates, while generally increasing from low 2010 levels, have not markedly surpassed high trail densities measured in 2007.

25 Table 4. Average trail (meters) density per point at Xeric Thorn Woodland sites, 2005-2012. Year 2005 2006 2007 2008 2009 2010 2011 2012 Chemehuevi Wash 99.68 119.63 143.03 65.92 59.24 86.83 80.29 Chuckwalla Thicket 9.00 Copper Basin 19.59 63.86 71.63 27.59 48.77 39.68 Corn Spring 29.43 Little Picacho Wilderness 43.58 52.92 45.58 59.67 12.50 37.17 McCoy Wash 6.50 18.87 56.00 42.47 16.67 No 86.23 Milpitas Wash 87.57 178.01 202.49 62.49 92.14 59.21 192.30 North of Palen-McCoy Wilderness Surveys 40.29 Palen McCoy Wilderness 0.00 Picacho Wash 201.44 168.14 406.76 665.03 332.66 464.57 Palo Verde Mountains Wilderness 3.33 6.19 2.86 18.52 112.14 28.38 Red Cloud Wash 136.21 48.79 114.96 Riverside Mountains Wilderness 80.41 61.44 101.63 45.63 69.00 30.03 Salt Creek 96.46 188.29 263.92 Upper Chemehuevi Wash 38.05 45.61 13.00 2.10 7.76 35.78 64.61 Vidal Wash 76.02 182.18 196.14 82.20 187.16 130.92 Whipple Mountains Wilderness 33.79 27.15 25.84 22.74 28.63 24.47

26 2.1 RECOMMENDATIONS

We have provided several management recommendations previously (McCreedy 2011). As we established several new study sites in 2012, we will include monitoring recommendations here:

1. Continue point count monitoring at xeric thorn woodland study sites. To our knowledge, this project represents the longest-continuing point count study of Sonoran Desert passerines, and it is the largest in geographic scope. Our study species have often been rarely studied in the past, and this project has provided a great deal of data and expertise to California Partners In Flight, the Sonoran Joint Venture, The California Bird Species of Special Concern species accounts, to the Arizona Bird Conservation Initiative, and to other studies in the region, particularly solar-related studies that otherwise lacked baseline data. We will continue to two manuscripts on our work in 2013 (McCreedy in prep), and we have been invited to author the revised Black-tailed Gnatcatcher account for the Birds of North America during the upcoming winter.

All of these contributions have occurred because of the span of our data set. Yet we have only just began to gather sufficient replicates of wet, dry, and average rainfall seasons for a sample size. Surveys did not occur in 2011, interrupting the study’s time series, and there is a strong probability that surveys will again not occur in 2013.

In the event that funding limitations constrain monitoring to only a fraction of study sites, a priority list of study sites includes:

Core study sites

Chemehuevi Wash Upper Chemehuevi Wash Milpitas Wash Vidal Wash McCoy Wash Riverside Mountains Wilderness

Long term study sites but with one less year of data than core study sites

Picacho Wash Little Picacho Wilderness Whipple Mountains Wilderness Copper Basin Palo Verde Mountains Wilderness

Chuckwalla Mountains sites

Red Cloud Wash Salt Creek Corn Spring

Palen-McCoy sites

Palen-McCoy Wilderness North of Palen-McCoy Wilderness Chuckwalla Thicket

27

2. Reassess Mojave Wilderness points in wetter conditions to gain a better understanding on variation in abundance, diversity and richness found at control and treatment points. Detection rates were very low at new Mojave Wilderness points in 2012. Black-throated Sparrows may be the only species with enough detections for analysis with program DISTANCE, though this is doubtful. In addition, we were unable to confirm breeding at Mojave Wilderness sites (for any species) because extreme drought conditions postponed nest initiation dates for all species. Bird species diversity, richness, and abundance have high variation in arid habitats, and this variation needs to be better captured for a proper baseline in future comparisons.

3. Reinstitute nest monitoring at Chemehuevi Wash, add additional nest monitoring plots for replication. Assessing the potential for OHV-recreation impacts on nesting success provided us with invaluable insight into direct species responses to OHV-recreation. Five years of nest monitoring provided us with hard- earned knowledge of nesting phenology and species’ response to drought that have framed the future direction of our work. Continual presence on nest plots allowed us to directly assess levels of OHV-use (vehicles per hour), rather than indirectly, via trail density. Monitoring recreation pressure in this direct way demonstrated that rates of OHV-use decrease over the course of the breeding season, decreasing chances for the possibility of nesting failure due to recreation pressure.

28 LITERATURE CITED

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BROOKS, M.L. AND B.M. LAIR. 2009. Ecological effects of vehicular routes in a desert ecosystem. In: Webb, Robert, Robert H., Fenstermaker, Lynn F., Heaton, Jill S., Hughson, Debra L., McDonald, Eric V., Miller, David M. (Eds.), The Mojave Desert: Ecosystem Processes and Sustainability. University of Nevada Press, Reno, Nevada. pp. 168-195.

CORMAN, T.E. AND C. WISE-GERVAIS. 2005. Arizona Breeding Bird Atlas. University of New Mexico Press. Albuquerque, N.M.

ENGLAND, A.S. AND W.F. LAUDENSLAYER. 1989. Distribution and seasonal movements of Bendire’s Thrasher in California. Western Birds 20: 97-123.

ESRI. 2000. ArcView Geographic Information System version 3.2a. Environmental Systems Research Institute, Inc. Redlands, CA.

FANCY, S.G. AND J.R. SAUER. 2000. Recommended methods for inventorying and monitoring landbirds in national parks. http://science.nature.nps.gov/im/monitor/protocols/birds.htm

KREBS, C.J. 1989. Ecological Methodology. Harper and Row Publishers, New York, New York: 654 pp.

MACARTHUR, R.H. 1965. Patterns of species diversity. Biological Reviews 40:510-533.

MASSEY, B.W. 1998. Guide to Birds of the Anza-Borrego Desert. Anza-Borrego Desert Natural History Association. Borrego Springs, CA.

MCCREEDY, C. 2011. Birds of Sonoran Desert Xeric Thorn Woodlands: Patterns of Bird Species Composition, Richness, Abundance, and Nest Survivorship, 2003-2010. PRBO Conservation Science (Contrib. No. 1861), 3820 Cypress Drive No.11, Petaluma, CA 94954.

MCCREEDY, C. 2004. Xeric riparian songbird conservation: 2003 progress report. PRBO Conservation Science (Contrib. 1180), 3820 Cypress Drive No.11, Petaluma, CA 94954.

MCCREEDY, C., C. HOWELL, AND L. CULP. 2005. Xeric riparian songbird project: 2004 progress report. PRBO Conservation Science (Contrib. 1309), 3820 Cypress Drive No.11, Petaluma, CA 94954.

NUR, N., S.L. JONES, AND G.R. GEUPEL. 1999. A statistical guide to data analysis of avian monitoring programs. U.S. Department of the Interior, Fish and Wildlife Service, BTP-R6001-1999, Washington D.C.

PATTEN, M.A., G. MCCASKIE, AND P. UNITT. 2003. Birds of the Salton Sea. University of California Press. Berkeley, CA.

RALPH, C.J., G.R. GEUPEL, P. PYLE., T.E. MARTIN, AND D.F. DESANTE. 1993. Field methods for monitoring landbirds. USDA Forest Service Publication: PSW-GTR 144.

RALPH, C.J., S. DROEGE, AND J.R. SAUER. 1995. Monitoring bird populations by point counts. USDA Forest Service Publication: PSW-GTR-149.

ROSENBERG, K.V., R.D. OHMART, W.C. HUNTER, AND B.W. ANDERSON. 1991. Birds of the Lower Colorado River Valley. University of Arizona Press. Tucson, AZ.

29 SAWYER , J.O., AND T. KEELER-WOLF. 1995. A Manual of California Vegetation. California Native Plant Society, Sacramento, CA.

STATA CORPORATION. 2003. Stata statistical software, Release 8.0. Stata Corporation, College Station, TX.

STERLING, J. in Shuford, W.D and Gardali, T., editors. 2008. California Birds Species of Special Concern: A ranked assessment of species, subspecies, and distinct populations of birds of immediate conservation concern in California. Studies of Western Birds 1. Western Field Ornithologists, Camarillo, California, and California Department of Fish and Game, Sacramento.

30 APPENDIX A. New 2012 Xeric Thorn Woodland Points. Chuckwalla Thicket; UTM NAD83 Z11

STATION SITE POINT_ID utme utmn CHUTHI 1 CHUTHI01 690750 3716500 CHUTHI 2 CHUTHI02 690750 3716750 CHUTHI 3 CHUTHI03 691000 3716750 CHUTHI 4 CHUTHI04 691250 3716750 CHUTHI 5 CHUTHI05 691500 3716750 CHUTHI 6 CHUTHI06 691750 3717000 CHUTHI 7 CHUTHI07 692000 3717250 CHUTHI 8 CHUTHI08 692250 3717500 CHUTHI 9 CHUTHI09 692500 3717750 CHUTHI 10 CHUTHI10 691000 3718500 CHUTHI 11 CHUTHI11 691000 3718750 CHUTHI 12 CHUTHI12 691000 3719000

31 APPENDIX A. New 2012 Xeric Thorn Woodland Points. Corn Spring; UTM NAD83 Z11

STATION SITE POINT_ID utme utmn CORSPR 1 COSP01 655000 3722250 CORSPR 2 COSP02 654750 3722250 CORSPR 3 COSP03 654500 3722250 CORSPR 4 COSP04 654250 3722250 CORSPR 5 COSP05 654000 3722250 CORSPR 6 COSP06 653750 3722250 CORSPR 7 COSP07 653750 3722500 CORSPR 8 COSP08 653500 3722250 CORSPR 9 COSP09 653500 3722500 CORSPR 10 COSP10 653250 3722500 CORSPR 11 COSP11 653000 3722500 CORSPR 12 COSP12 652750 3722750 CORSPR 13 COSP13 652500 3722750 CORSPR 14 COSP14 652250 3722750 CORSPR 15 COSP15 652250 3723000 CORSPR 16 COSP16 657750 3722000 CORSPR 17 COSP17 658000 3722250 CORSPR 18 COSP18 658000 3722500 CORSPR 19 COSP19 658000 3722750 CORSPR 20 COSP20 658250 3723000 CORSPR 21 COSP21 658250 3723250 CORSPR 22 COSP22 658000 3723250 CORSPR 23 COSP23 658500 3723500 CORSPR 24 COSP24 658500 3723750 CORSPR 25 COSP25 658500 3724000 CORSPR 26 COSP26 658750 3724000 CORSPR 27 COSP27 658250 3724000 CORSPR 28 COSP28 658500 3724250 CORSPR 29 COSP29 658750 3724250 CORSPR 30 COSP30 658750 3724500

32 APPENDIX A. New 2012 Xeric Thorn Woodland Points. North of Palen-McCoy Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utme utmn NOPAMC 1 NOPA01 689750 3744500 NOPAMC 2 NOPA02 690000 3744750 NOPAMC 3 NOPA03 690250 3745000 NOPAMC 4 NOPA04 690500 3745000 NOPAMC 5 NOPA05 690500 3745250 NOPAMC 6 NOPA06 690750 3745000 NOPAMC 7 NOPA07 690750 3745250 NOPAMC 8 NOPA08 691000 3745000 NOPAMC 9 NOPA09 691000 3745250 NOPAMC 10 NOPA10 691250 3745250 NOPAMC 11 NOPA11 691500 3745250 NOPAMC 12 NOPA12 691500 3745500 NOPAMC 13 NOPA13 691750 3745250 NOPAMC 14 NOPA14 692000 3745250 NOPAMC 15 NOPA15 692000 3745500 NOPAMC 16 NOPA16 692250 3745250 NOPAMC 17 NOPA17 692500 3745250 NOPAMC 18 NOPA18 692750 3745250 NOPAMC 19 NOPA19 693000 3745250 NOPAMC 20 NOPA20 693500 3745000 NOPAMC 21 NOPA21 694000 3744750 NOPAMC 22 NOPA22 694500 3744500 NOPAMC 23 NOPA23 694750 3744500 NOPAMC 24 NOPA24 695000 3744500

33 APPENDIX A. New 2012 Xeric Thorn Woodland Points. Palen-McCoy Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utme utmn PAMCWI 1 PAMC01 688750 3743000 PAMCWI 2 PAMC02 688750 3742750 PAMCWI 3 PAMC03 688750 3742500 PAMCWI 4 PAMC04 688750 3742250 PAMCWI 5 PAMC05 688500 3742250 PAMCWI 6 PAMC06 688500 3742000 PAMCWI 7 PAMC07 688750 3742000 PAMCWI 8 PAMC08 688500 3741750 PAMCWI 9 PAMC09 688750 3741750 PAMCWI 10 PAMC10 689250 3741750 PAMCWI 11 PAMC11 688500 3741500 PAMCWI 12 PAMC12 688750 3741500 PAMCWI 13 PAMC13 688500 3741250 PAMCWI 14 PAMC14 688750 3741250 PAMCWI 15 PAMC15 689000 3741250 PAMCWI 16 PAMC16 688500 3741000 PAMCWI 17 PAMC17 688750 3741000 PAMCWI 18 PAMC18 689000 3741000 PAMCWI 19 PAMC19 688750 3740750 PAMCWI 20 PAMC20 689000 3740750 PAMCWI 21 PAMC21 688750 3740500 PAMCWI 22 PAMC22 689000 3740500 PAMCWI 23 PAMC23 688750 3740250 PAMCWI 24 PAMC24 688750 3740000

34 APPENDIX A. New 2012 Mojave Wilderness Points. Eastern Mesquite Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utmn utme EAMEWI 1 EAMEWI01 630350 3948061 EAMEWI 2 EAMEWI02 630107 3948121 EAMEWI 3 EAMEWI03 629863 3948182 EAMEWI 4 EAMEWI04 629620 3948242 EAMEWI 5 EAMEWI05 629377 3948304 EAMEWI 6 EAMEWI06 629134 3948368 EAMEWI 7 EAMEWI07 628892 3948429 EAMEWI 8 EAMEWI08 628648 3948489 EAMEWI 9 EAMEWI09 628406 3948489 EAMEWI 10 EAMEWI10 628163 3948612 EAMEWI 11 EAMEWI11 627921 3948676 EAMEWI 12 EAMEWI12 627678 3948739 EAMEWI 13 EAMEWI13 633905 3946871 EAMEWI 14 EAMEWI14 633938 3946624 EAMEWI 15 EAMEWI15 633951 3946375 EAMEWI 16 EAMEWI16 634025 3946136 EAMEWI 17 EAMEWI17 634062 3945889 EAMEWI 18 EAMEWI18 634162 3945660 EAMEWI 19 EAMEWI19 634299 3945451 EAMEWI 20 EAMEWI20 634484 3945285 EAMEWI 21 EAMEWI21 634594 3945060 EAMEWI 22 EAMEWI22 634756 3944869 EAMEWI 23 EAMEWI23 634940 3944699 EAMEWI 24 EAMEWI24 635054 3944478 EAMEWI 25 EAMEWI25 625750 3945000 EAMEWI 26 EAMEWI26 625750 3945250 EAMEWI 27 EAMEWI27 625750 3945500 EAMEWI 28 EAMEWI28 626000 3945250 EAMEWI 29 EAMEWI29 626000 3945000 EAMEWI 30 EAMEWI30 626250 3945250 EAMEWI 31 EAMEWI31 626250 3945250 EAMEWI 32 EAMEWI32 626500 3945500 EAMEWI 33 EAMEWI33 626500 3945250 EAMEWI 34 EAMEWI34 626500 3945000 EAMEWI 35 EAMEWI35 626250 3945000 EAMEWI 36 EAMEWI36 626500 3944750 EAMEWI 37 EAMEWI37 630500 3947500 EAMEWI 38 EAMEWI38 630500 3947250

35 EAMEWI 39 EAMEWI39 630250 3947250 EAMEWI 40 EAMEWI40 630250 3947000 EAMEWI 41 EAMEWI41 630250 3946751 EAMEWI 42 EAMEWI42 630000 3946750 EAMEWI 43 EAMEWI43 630000 3947000 EAMEWI 44 EAMEWI44 630000 3947250 EAMEWI 45 EAMEWI45 630000 3947500 EAMEWI 46 EAMEWI46 630000 3947750 EAMEWI 47 EAMEWI47 630250 3947750 EAMEWI 48 EAMEWI48 630500 3947750

36 APPENDIX A. New 2012 Mojave Wilderness Points. Kingston Range Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utmn utme KIRAWI 1 KIRAWI01 611493 3946486 KIRAWI 2 KIRAWI02 611318 3946667 KIRAWI 3 KIRAWI03 611193 3946889 KIRAWI 4 KIRAWI04 611138 3947129 KIRAWI 5 KIRAWI05 611081 3947363 KIRAWI 6 KIRAWI06 611017 3947605 KIRAWI 7 KIRAWI07 610956 3947847 KIRAWI 8 KIRAWI08 610896 3948088 KIRAWI 9 KIRAWI09 611674 3946315 KIRAWI 10 KIRAWI10 611847 3946136 KIRAWI 11 KIRAWI11 612021 3945957 KIRAWI 12 KIRAWI12 612160 3945750 KIRAWI 13 KIRAWI13 612286 3945535 KIRAWI 14 KIRAWI14 612416 3945323 KIRAWI 15 KIRAWI15 612545 3945111 KIRAWI 16 KIRAWI16 612669 3944896 KIRAWI 17 KIRAWI17 612796 3944681 KIRAWI 18 KIRAWI18 612923 3944469 KIRAWI 19 KIRAWI19 613048 3944256 KIRAWI 20 KIRAWI20 613178 3944042 KIRAWI 21 KIRAWI21 613310 3943827 KIRAWI 22 KIRAWI22 613438 3943612 KIRAWI 23 KIRAWI23 613566 3943397 KIRAWI 24 KIRAWI24 613694 3943183 KIRAWI 25 KIRAWI25 609500 3947000 KIRAWI 26 KIRAWI26 609500 3946750 KIRAWI 27 KIRAWI27 609250 3946750 KIRAWI 28 KIRAWI28 609750 3946750 KIRAWI 29 KIRAWI29 609750 3946500 KIRAWI 30 KIRAWI30 609000 3946750 KIRAWI 31 KIRAWI31 609000 3947000 KIRAWI 32 KIRAWI32 609000 3946500 KIRAWI 33 KIRAWI33 609000 3946250 KIRAWI 34 KIRAWI34 609250 3946500 KIRAWI 35 KIRAWI35 609250 3946250 KIRAWI 36 KIRAWI36 609250 3946000 KIRAWI 37 KIRAWI37 612250 3945000 KIRAWI 38 KIRAWI38 612250 3944750

37 KIRAWI 39 KIRAWI39 612000 3944750 KIRAWI 40 KIRAWI40 611750 3944750 KIRAWI 41 KIRAWI41 612250 3944500 KIRAWI 42 KIRAWI42 612250 3944250 KIRAWI 43 KIRAWI43 612500 3944500 KIRAWI 44 KIRAWI44 612500 3944250 KIRAWI 45 KIRAWI45 612750 3944250 KIRAWI 46 KIRAWI46 612500 3944000 KIRAWI 47 KIRAWI47 612750 3944000 KIRAWI 48 KIRAWI48 612500 3943750

38 APPENDIX A. New 2012 Mojave Wilderness Points. Mesquite Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utme utmn MESQWI 1 MESQWI01 616590 3946486 MESQWI 2 MESQWI02 616676 3946719 MESQWI 3 MESQWI03 616763 3946953 MESQWI 4 MESQWI04 616788 3947201 MESQWI 5 MESQWI05 616811 3947449 MESQWI 6 MESQWI06 616824 3947698 MESQWI 7 MESQWI07 616847 3947946 MESQWI 8 MESQWI08 616866 3948194 MESQWI 9 MESQWI09 616515 3946249 MESQWI 10 MESQWI10 616439 3946012 MESQWI 11 MESQWI11 616386 3945768 MESQWI 12 MESQWI12 616308 3945531 MESQWI 13 MESQWI13 616234 3945293 MESQWI 14 MESQWI14 616163 3945054 MESQWI 15 MESQWI15 616086 3944817 MESQWI 16 MESQWI16 615995 3944583 MESQWI 17 MESQWI17 615907 3944350 MESQWI 18 MESQWI18 615840 3944108 MESQWI 19 MESQWI19 615755 3943872 MESQWI 20 MESQWI20 615663 3943637 MESQWI 21 MESQWI21 615567 3943405 MESQWI 22 MESQWI22 615497 3943164 MESQWI 23 MESQWI23 615425 3942922 MESQWI 24 MESQWI24 615342 3942688 MESQWI 25 MESQWI25 617500 3939500 MESQWI 26 MESQWI26 617500 3939250 MESQWI 27 MESQWI27 617500 3939000 MESQWI 28 MESQWI28 617250 3939000 MESQWI 29 MESQWI29 617250 3939250 MESQWI 30 MESQWI30 617750 3939000 MESQWI 31 MESQWI31 617750 3939250 MESQWI 32 MESQWI32 618000 3939250 MESQWI 33 MESQWI33 618000 3939500 MESQWI 34 MESQWI34 618250 3939500 MESQWI 35 MESQWI35 618000 3939750 MESQWI 36 MESQWI36 618250 3939750 MESQWI 37 MESQWI37 615500 3941750 MESQWI 38 MESQWI38 615500 3942000

39 MESQWI 39 MESQWI39 615500 3942250 MESQWI 40 MESQWI40 615750 3942250 MESQWI 41 MESQWI41 616000 3942250 MESQWI 42 MESQWI42 616000 3942000 MESQWI 43 MESQWI43 616250 3942250 MESQWI 44 MESQWI44 616250 3942500 MESQWI 45 MESQWI45 616500 3942500 MESQWI 46 MESQWI46 616000 3942500 MESQWI 47 MESQWI47 616000 3942750 MESQWI 48 MESQWI48 615750 3942500

40 APPENDIX A. New 2012 Mojave Wilderness Points. North Mesquite Mountains Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utme Utmn NOMEWI 1 NOMEWI01 616803 3956736 NOMEWI 2 NOMEWI02 616555 3956706 NOMEWI 3 NOMEWI03 616306 3956674 NOMEWI 4 NOMEWI04 616058 3956641 NOMEWI 5 NOMEWI05 615808 3956617 NOMEWI 6 NOMEWI06 615560 3956590 NOMEWI 7 NOMEWI07 615311 3956545 NOMEWI 8 NOMEWI08 615063 3956513 NOMEWI 9 NOMEWI09 614816 3956470 NOMEWI 10 NOMEWI10 614569 3956432 NOMEWI 11 NOMEWI11 614322 3956392 NOMEWI 12 NOMEWI12 614088 3956301 NOMEWI 13 NOMEWI13 616500 3958000 NOMEWI 14 NOMEWI14 616750 3958000 NOMEWI 15 NOMEWI15 616250 3958000 NOMEWI 16 NOMEWI16 616250 3958250 NOMEWI 17 NOMEWI17 616500 3958250 NOMEWI 18 NOMEWI18 616250 3957750 NOMEWI 19 NOMEWI19 616000 3958250 NOMEWI 20 NOMEWI20 616000 3958500 NOMEWI 21 NOMEWI21 616250 3958500 NOMEWI 22 NOMEWI22 616250 3958750 NOMEWI 23 NOMEWI23 616500 3958750 NOMEWI 24 NOMEWI24 616500 3958500

41 APPENDIX A. New 2012 Mojave Wilderness Points. Stateline Wilderness; UTM NAD83 Z11

STATION SITE POINT_ID utme utmn STATWI 1 STATWI01 641841 3944229 STATWI 2 STATWI02 641636 3944371 STATWI 3 STATWI03 641434 3944518 STATWI 4 STATWI04 641282 3944716 STATWI 5 STATWI05 641080 3944863 STATWI 6 STATWI06 640856 3944973 STATWI 7 STATWI07 640627 3945073 STATWI 8 STATWI08 640383 3945129 STATWI 9 STATWI09 640145 3945205 STATWI 10 STATWI10 639952 3945362 STATWI 11 STATWI11 639978 3945558 STATWI 12 STATWI12 639602 3945717 STATWI 13 STATWI13 639464 3945925 STATWI 14 STATWI14 639370 3946156 STATWI 15 STATWI15 639214 3946351 STATWI 16 STATWI16 640500 3944000 STATWI 17 STATWI17 640500 3943750 STATWI 18 STATWI18 640750 3943750 STATWI 19 STATWI19 640750 3943500 STATWI 20 STATWI20 640750 3943250 STATWI 21 STATWI21 641000 3943500 STATWI 22 STATWI22 641000 3943750 STATWI 23 STATWI23 641000 3944000 STATWI 24 STATWI24 641250 3944000 STATWI 25 STATWI25 641250 3943750 STATWI 26 STATWI26 641250 3943500 STATWI 27 STATWI27 641500 3943500 STATWI 28 STATWI28 641500 3943250 STATWI 29 STATWI29 641750 3943250 STATWI 30 STATWI30 641750 3943500

42 APPENDIX B. Plant species encountered during habitat assessments (USDA PLANTS Database).

SPECIES CODE LATIN NAME COMMON NAME FAMILY BRASSI Brassicaceous forb Brassicaceae ACGR Acacia greggii Gray catclaw acacia Fabaceae AMARA Amaranthus L. pigweed Amaranthaceae AMDU2 Ambrosia dumosa (Gray) Payne white burrobush Asteraceae AMIL2 Ambrosia ilicifolia (Gray) Payne hollyleaf burr ragweed Asteraceae AMTE3 Amsinckia tessellata Gray bristly fiddleneck Boraginaceae AMTO2 Amsonia tomentosa Torr. & Frem. woolly bluestar Apocynaceae ARCO6 Argemone corymbosa Greene Mojave pricklypoppy Papaveraceae ASCLE Asclepias L. milkweed Asclepiadaceae ASTRA Astragalus L. milkvetch Fabaceae ATPL Atrichoseris platyphylla (Gray) Gray parachute plant Asteraceae ATRIP Atriplex Unknown saltbush (CJR) BEJUA Bebbia juncea var. aspera Greene sweetbush Asteraceae BRBI Brandegea bigelovii (S. Wats.) Cogn. desert starvine Cucurbitaceae BRTO Brassica tournefortii Gouan Asian mustard Brassicaceae BROMU Bromus L. brome Poaceae CABR23 Camissonia brevipes (Gray) Raven yellow cups Onagraceae CACL4 Camissonia claviformis (Torr. & Frem.) Raven browneyes Onagraceae CAGI10 Carnegiea gigantea (Engelm.) Britton & Rose saguaro Cactaceae CAEM4 Castela emoryi (Gray) Moran & Felger thorn of Christ Simaroubaceae CEFL6 Parkinsonia florida Benth. ex Gray = Parkinsonia florida Fabaceae CEMI6 Parkinsonia microphylla (Torr.) Rose & I.M. Johnsto = Parkinsonia microphylla Fabaceae CHAEN Chaenactis DC. chaenactis Asteraceae CHLIA Chilopsis linearis ssp. arcuata (Fosberg) Henricks desert willow Bignoniaceous CHRYS Chrysothamnus Nutt. rabbitbrush Asteraceae CONDA Condalia Cav. condalia Rhamnaceae CRYPT Cryptantha Lehm. ex G. Don cryptantha Boraginaceae CUSCU Cuscuta L. dodder Cuscutaceae ENFA Encelia farinosa Gray ex Torr. goldenhills Asteraceae ENVI Encelia virginensis A. Nels. Virgin River brittlebush Asteraceae EPHED Ephedra L. ephedra Ephedraceae ERRO8 Eremalche rotundifolia (Gray) Greene desert fivespot Malvaceae ERGI2 Eriogonum giganteum S. Wats. St. Catherine's lace Polygonaceae ERIN4 Eriogonum inflatum Torr. & Frem. Native American pipeweed Polygonaceae ERIOG Eriogonum Michx. eriogonum Polygonaceae ERCI6 Erodium cicutarium (L.) L'Her. ex Ait. redstem stork's bill, filaree Geraniaceae ESCHS Eschscholzia Cham. goldenpoppy Papaveraceae EUPHO Euphorbia L. spurge Euphorbiaceae FECY Ferocactus cylindraceus (Engelm.) Orcutt California barrel cactus Cactaceae FOSP2 Fouquieria splendens Engelm. ocotillo Fouquieriaceae HEUN2 Hesperocallis undulata Gray desertlily Liliaceae HYSA Hymenoclea salsola Torr. & Gray ex Gray white burrobush Asteraceae HYEM Hyptis emoryi Torr. desert lavender Lamiaceae KRGR Krameria grayi Rose & Painter white ratany Krameriaceae

43

SPECIES CODE LATIN NAME COMMON NAME FAMILY LATR2 Larrea tridentata (Sesse & Moc. ex DC.) Coville creosote bush Zygophyllaceae LEPID Lepidium L. pepperweed Brassicaceae LUPIN Lupinus L. lupine Fabaceae LYCIU Lycium L. wolfberry Solanaceae NICOT Nicotiana L. tobacco Solanaceae OLTE Olneya tesota Gray desert ironwood Fabaceae OPACC Opuntia acanthocarpa var. coloradensis L. Benson Colorado buckhorn cholla Cactaceae OPBA2 Opuntia basilaris Engelm. & Bigelow beavertail pricklypear Cactaceae OPRA Opuntia ramosissima Engelm. branched pencil cholla Cactaceae PEEM Perityle emoryi Torr. Emory's rocklily Asteraceae PETHT Petalonyx thurberi ssp. thurberi Gray Thurber's sandpaper plant Loasaceae PESC4 Peucephyllum schottii Gray Schott's pygmy cedar Asteraceae PHACE Phacelia Juss. phacelia Hydrophyllaceae PHCA8 Phoradendron californicum Nutt. mesquite mistletoe Viscaceae PLANT Plantago L. plantain Plantaginaceae PLSE Pluchea sericea (Nutt.) Coville arrowweed Asteraceae PRGLT Prosopis glandulosa var. torreyana (L. Benson) M.C western honey mesquite Fabaceae PSFR Psorothamnus fremontii (Torr. ex Gray) Barneby Fremont's dalea Fabaceae PSSP3 Psorothamnus spinosus (Gray) Barneby smoketree Fabaceae RANUN Ranunculus L. buttercup Ranunculaceae SAME Salazaria mexicana Torr. Mexican bladdersage Lamiaceae SACO6 Salvia columbariae Benth. chia Lamiaceae SARCO Sarcostemma R. Br. viney milkweed Asclepiadaceae SCHIS Schismus Beauv. Mediterranean grass Poaceae SPAM2 Sphaeralcea ambigua Gray desert globemallow Malvaceae STPI Stanleya pinnata (Pursh) Britt. desert princesplume Brassicaceae STEPH Stephanomeria Nutt. wirelettuce Asteraceae TAMAR Tamarix L. tamarisk Tamaricaceae

44 APPENDIX C. Bird Species Lists with breeding statuses.

Appendix C. List of all bird species detected at all sites using all methods in San Bernardino County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. HAVCAL= Havasu NWR, California side; UPCHWA= Upper Chemehuevi Wash (low OHV-use); CHEWAS= Chemehuevi Wash (high OHV-use); WHMOMI = Whipple Mountains Wilderness; COPBAS= Copper Basin; VIDWAS= Vidal Wash. Sites are situated in Sonoran Desert Xeric Woodland, while HAVC and CHEW also include Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name HAVCAL UPCHWA CHEWAS WHMOWI COPBAS VIDWAS Snow Goose Chen caerulescens 0 0 Canada Goose Branta canadensis 0 0 0 American Wigeon Anas americana 0 Mallard Anas platyrynchos 2 0 Northern Shoveler Anas clypeata 0 0 Canvasback Aythya valisineria 0 Redhead Aythya americana 0 Bufflehead Bucephala albeola 0 Gambel's Quail Callipepla gambelii 3 1 1 1 3 3 Common Loon Gavia immer 0 Pied-billed Grebe Podilymbus podiceps 2 Eared Grebe Podiceps nigricollis 0 Clark's Grebe Aechmophorus clarkii 0 0 American White Pelican Pelecanus erythrorhynchos 0 0 0 Double-crested Cormorant Phalacrocorax auritus 0 0 Least Bittern Ixobrychus exilis 2 2 Great Blue Heron Ardea herodias 0 Great Egret Ardea alba 0 0 0 Snowy Egret Egretta thula 0 Turkey Vulture Cathartes aura 2 2 2 2 2 2 Osprey Pandion haliaetus 0 0 Bald Eagle Haliaeetus leucocephalus 0 Northern Harrier Circus cyaneus 0 0 0 Sharp-shinned Hawk Accipiter striatus 0 0 Cooper's Hawk Accipiter cooperii 0 0 0 0 0 Swainson's Hawk Buteo swainsoni 0 0 Red-tailed Hawk Buteo jamaicensis 2 2 1 2 2 1 Golden Eagle Aquila chrysaetos 0 0 Clapper Rail Rallus longirostris 2 0 Virginia Rail Rallus limicola 2 Common Moorhen Gallinula chloropus 0 American Coot Fulica americana 3 0 Sandhill Crane Grus canadensis 0 0 0 Killdeer Charadrius vociferus 0 0 0 American Avocet Recurvirostra americana 0 Spotted Sandpiper Actitus macularius 0 0 Wilson's Snipe Gallinago delicata 0 Ring-billed Gull Larus delawarensis 0 0 Rock Pigeon Columba livia 0 Eurasian Collared-Dove Streptopelia decaocto 1 1 0 White-winged Dove Zenaida asiatica 3 1 1 2 2 2 Mourning Dove Zenaida macroura 1 1 1 1 1 1 Common Ground-dove Columbina passerina 0 Greater Roadrunner Geococcyx californicus 1 1 1 2 2 2

45 Appendix C. List of all bird species detected at all sites using all methods in San Bernardino County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. HAVCAL= Havasu NWR, California side; UPCHWA= Upper Chemehuevi Wash (low OHV-use); CHEWAS= Chemehuevi Wash (high OHV-use); WHMOMI = Whipple Mountains Wilderness; COPBAS= Copper Basin; VIDWAS= Vidal Wash. Sites are situated in Sonoran Desert Xeric Woodland, while HAVC and CHEW also include Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name HAVCAL UPCHWA CHEWAS WHMOWI COPBAS VIDWAS Barn Owl Tyto alba 0 0 0 0 Western Screech-owl Megascops kennicottii 2 3 1 2 Great-horned Owl Bubo virginianus 2 1 3 3 Elf Owl Micrathene whitneyi 0 Long-eared Owl Asio otus 1 2 1 Lesser Nighthawk Chordeiles acutipennis 3 3 1 3 1 2 Common Poorwill Phalaenoptilus nuttalli 2 2 2 2 2 Vaux's Swift Chaetura vauxi 0 0 0 White-throated Swift Aeronautes saxatalis 3 0 1 1 3 0 Black-chinned Hummingbird Archilochus alexandri 2 2 0 0 Anna's Hummingbird Calypte anna 2 2 1 2 1 1 Costa's Hummingbird Calypte costae 1 1 1 1 1 1 Calliope Hummingbird Stellula calliope 0 0 0 Broad-tailed Hummingbird Selasphorus platycerus 0 Rufous Hummingbird Selasphorus rufus 0 0 0 0 Williamson's Sapsucker Sphyrapicus thryoideus 0 Red-naped Sapsucker Sphyrapicus nuchalis 0 Ladder-backed Woodpecker Picoides scalaris 3 1 1 1 3 1 Northern (Red-shafted) Flicker Colaptes auratus 0 0 0 Northern (Yellow-shafted) Flicker Colaptes auratus 0 American Kestrel Falco sparverius 2 2 1 2 2 2 Peregrine Falcon Falco peregrinus 0 Prairie Falcon Falco mexicanus 0 0 1 1 0 Olive-sided Flycatcher Contopus cooperi 0 0 Western Wood-pewee Contopus sordidulus 0 0 0 0 0 Willow Flycatcher Empidonax traillii 2 0 Hammond's Flycatcher Empidonax hammondii 0 0 0 0 0 0 Gray Flycatcher Empidonax wrightii 0 0 0 0 0 0 Dusky Flycatcher Empidonax olberholseri 0 0 0 0 0 0 Western Flycatcher Empidonax difficilis 0 0 0 0 0 0 Black Phoebe Sayornis nigricans 2 0 0 0 Say's Phoebe Sayornis saya 1 2 1 1 1 0 Vermilion Flycatcher Pyrocephalus rubinus 0 0 Ash-throated Flycatcher Myiarchus cinerascens 1 1 1 1 1 1 Cassin's Kingbird Tyrannus vociferans 0 Western Kingbird Tyrannus verticalis 2 1 1 0 0 1 Loggerhead Shrike Lanius ludovicianus 1 1 1 1 1 1 Bell's Vireo Vireo bellii 3 1 2 0 Gray Vireo Vireo vicinior 0 Plumbeous Vireo Vireo plumbeus 0 0 0 Cassin's Vireo Vireo cassinii 0 0 0 0 0 Warbling Vireo Vireo gilvus 0 0 0 0 0 Western Scrub-jay Aphelocoma californica 0 0 0 Common Raven Corvus brachyrhynchos 0 Common Raven Corvus corax 1 3 1 3 3 1 Horned Lark Eremophila alpestris 0 3 1 2 Tree Swallow Tachycineta bicolor 0 0 0 0 0 0 Violet-green Swallow Tachycineta thalassina 0 0 0 0 0 0 Northern Rough-winged Swallow Stelgidopteryx serripennis 3 0 1 2 2

46 Appendix C. List of all bird species detected at all sites using all methods in San Bernardino County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. HAVCAL= Havasu NWR, California side; UPCHWA= Upper Chemehuevi Wash (low OHV-use); CHEWAS= Chemehuevi Wash (high OHV-use); WHMOMI = Whipple Mountains Wilderness; COPBAS= Copper Basin; VIDWAS= Vidal Wash. Sites are situated in Sonoran Desert Xeric Woodland, while HAVC and CHEW also include Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name HAVCAL UPCHWA CHEWAS WHMOWI COPBAS VIDWAS Bank Swallow Riparia riparia 0 0 0 Cliff Swallow Petrochelidon pyrrhonata 1 0 0 0 Barn Swallow Hirundo rustica 0 0 0 0 0 Verdin Auriparus flaviceps 1 1 1 1 1 1 Campylorhynchus Cactus Wren brunneicapillus 2 1 1 3 1 2 Rock Wren Salpinctes obsoletus 1 3 1 1 3 2 Canyon Wren Catherpes mexicanus 1 2 3 2 Bewick's Wren Thryomanes bewickii 3 0 1 0 House Wren Troglodytes aedon 0 0 0 0 0 0 Marsh Wren Cistothorus palustris 2 Blue-gray Gnatcatcher Polioptila caerulea 0 0 0 0 0 0 Black-tailed Gnatcatcher Polioptila melanura 1 1 1 1 1 1 Ruby-crowned Kinglet Regulus calendula 0 0 0 0 0 0 Western Bluebird Sialia mexicana 0 0 Swainson's Thrush Catharus ustulatus 0 0 Hermit Thrush Catharus guttatus 0 American Robin Turdus migratorius 0 0 Northern Mockingbird Mimus polyglottos 1 1 1 1 1 3 Sage Thrasher Oreoscoptes montanus 2 2 0 Bendire's Thrasher Toxostoma bendirei 1 2 Crissal Thrasher Toxostoma crissale 1 1 1 2 3 LeConte's Thrasher Toxostoma lecontei 1 0 1 European Starling Sturnus vulgaris 0 0 0 American Pipit Anthus rubescens 0 0 Cedar Waxwing Bombycilla cedrorum 0 0 Phainopepla Phainopepla nitens 1 1 1 1 1 1 Ovenbird Seiurus aurocapilla 0 Orange-crowned Warbler Oreothlypis celata 0 0 0 0 0 0 Lucy's Warbler Oreothlypis luciae 1 1 1 1 1 1 Nashville Warbler Oreothlypis ruficapilla 0 0 0 0 0 0 Virginia's Warbler Oreothlypis virginiae 0 MacGillivray's Warbler Geothlypis tolmiei 0 0 0 0 0 Common Yellowthroat Geothlypis trichas 3 0 0 0 Northern Parula Setophaga americana 0 0 Yellow Warbler Setophaga petechia 0 0 0 0 0 Palm Warbler Setophaga palmarum 0 Yellow-rumped (Audubon's) Warbler Setophaga coronata 0 0 0 0 0 0 Yellow-rumped (Myrtle) Warbler Setophaga coronata 0 0 Black-throated Gray Warbler Setophaga nigrescens 0 0 0 0 0 Townsend's Warbler Setophaga townsendi 0 0 0 0 Hermit Warbler Setophaga occidentalis 0 0 Wilson's Warbler Cardellina pusilla 0 0 0 0 0 Yellow-breasted Chat Icteria virens 3 0 Green-tailed Towhee Pipilo chlorurus 0 0 0 0 0 0 Spotted Towhee Pipilo maculatus 0 Abert's Towhee Melozone aberti 1 2 0 2 Chipping Sparrow Spizella passerina 0 0 0 0 0 Brewer's Sparrow Spizella breweri 0 0 0 0 0 0

47 Appendix C. List of all bird species detected at all sites using all methods in San Bernardino County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. HAVCAL= Havasu NWR, California side; UPCHWA= Upper Chemehuevi Wash (low OHV-use); CHEWAS= Chemehuevi Wash (high OHV-use); WHMOMI = Whipple Mountains Wilderness; COPBAS= Copper Basin; VIDWAS= Vidal Wash. Sites are situated in Sonoran Desert Xeric Woodland, while HAVC and CHEW also include Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name HAVCAL UPCHWA CHEWAS WHMOWI COPBAS VIDWAS Black-chinned Sparrow Spizella atrogularis 0 Vesper Sparrow Pooecetes gramineus 0 0 0 Lark Sparrow Chondestes grammacus 0 0 0 Black-throated Sparrow Amphispiza bilineata 1 1 1 1 1 2 Sage Sparrow Amphispiza belli 0 0 0 Lark Bunting Calamospiza melanocorys 0 Savannah Sparrow Passerculus sandwichensis 0 Grasshopper Sparrow Ammodramus savannarum 0 Song Sparrow Melospiza melodia 3 Lincoln's Sparrow Melospiza lincolnii 0 0 0 0 White-throated Sparrow Zonotrichia albicollis 0 (Gambel's )White-crowned Sparrow Zonotrichia leucophrys 0 0 0 0 0 0 (Mountain)White-crowned Sparrow Zonotrichia leucophrys 0 0 0 Dark-eyed (Oregon) Junco Junco hyemalis 0 0 Dark-eyed (Slate-colored) Junco Junco hyemalis 0 Summer Tanager Piranga rubra 0 Western Tanager Piranga ludoviciana 0 0 0 0 0 Northern Cardinal Cardinalis cardinalis 0 Black-headed Grosbeak Pheucticus melanocephalus 0 0 0 0 0 0 Lazuli Bunting Passerina amoena 0 0 0 0 Indigo Bunting Passerina cyanea 0 Red-winged Blackbird Agelaius phoeniceus 0 0 0 0 Western Meadowlark Sturnella neglecta 0 2 2 0 Yellow-headed Blackbird Xanthocephalus xanthocephalus 0 0 0 0 Brewer's Blackbird Euphagus cyanocephalus 0 Great-tailed Grackle Quiscalus mexicanus 1 0 3 0 Brown-headed Cowbird Molothrus ater 2 1 1 0 3 Orchard Oriole Icterus spurius 0 Hooded Oriole Icterus cucullatus 0 0 0 0 0 Bullock's Oriole Icterus bullockii 2 2 1 2 2 2 Scott's Oriole Icterus parisorum 0 0 House Finch Carpodacus mexicanus 1 1 1 1 1 1 Pine Siskin Spinus pinus 0 Lesser Goldfinch Spinus psaltria 0 2 1 0 2 2 Lawrence's Goldfinch Spinus lawrencei 2 2 House Sparrow Passer domesticus 0 0

48

Appendix C. List of all bird species detected at all sites using all methods in Riverside County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. RIMOWI= Riverside Mountains Wilderness; BIGWAS= Big Wash; SLTRWA= Slaughter Tree Wash; MCCWAS= McCoy Wash; SALCRE= Salt Creek; RECLWA= Red Cloud Wash. Sites are situated in Sonoran Desert Xeric Woodland. Common Name Scientific Name RIMOWI BIGWAS SLTRWA MCCWAS SALCRE RECLWA Gambel's Quail Callipepla gambelii 3 3 1 3 3 White-faced Ibis Plegadis chihi 0 Turkey Vulture Cathartes aura 0 2 0 Osprey Pandion haliaetus 0 0 Northern Harrier Circus cyaneus 0 0 Sharp-shinned Hawk Accipiter striatus 0 0 0 Cooper's Hawk Accipiter cooperii 0 Swainson's Hawk Buteo swainsoni 0 Red-tailed Hawk Buteo jamaicensis 2 2 2 2 Killdeer Charadrius vociferus 0 Eurasian Collared-Dove Streptopelia decaocto 2 2 White-winged Dove Zenaida asiatica 2 0 0 2 2 2 Mourning Dove Zenaida macroura 1 2 2 3 3 1 Greater Roadrunner Geococcyx californicus 2 2 2 2 Western Screech-Owl Megascops kennicottii 2 Great-horned Owl Bubo virginianus 2 2 Long-eared Owl Asio otus 1 0 0 Lesser Nighthawk Chordeiles acutipennis 3 3 2 2 2 Common Poorwill Phalaenoptilus nuttalli 0 0 0 Vaux's Swift Chaetura vauxi 0 0 White-throated Swift Aeronautes saxatalis 2 0 Black-chinned Hummingbird Archilochus alexandri 0 0 0 Anna's Hummingbird Calypte anna 2 1 1 Costa's Hummingbird Calypte costae 2 2 3 3 1 Rufous Hummingbird Selasphorus rufus 0 0 Gila Woodpecker Melanerpes uropygialis 0 Ladder-backed Woodpecker Picoides scalaris 2 2 2 3 1 2 American Kestrel Falco sparverius 2 2 2 Prairie Falcon Falco mexicanus 0 Olive-sided Flycatcher Contopus cooperi 0 Western Wood-pewee Contopus sordidulus 0 Hammond's Flycatcher Empidonax hammondii 0 0 Gray Flycatcher Empidonax wrightii 0 0 0 Dusky Flycatcher Empidonax olberholseri 0 0 0 0 Western Flycatcher Empidonax difficilis 0 0 0 0 Say's Phoebe Sayornis saya 2 2 2 Vermillion Flycatcher Pyrocephalus rubinus 0 Ash-throated Flycatcher Myiarchus cinerascens 1 1 2 1 1 1 Western Kingbird Tyrannus verticalis 2 0 0 0 Loggerhead Shrike Lanius ludovicianus 1 3 1 1 1 1 Plumbeous Vireo Vireo plumbeus 0 Warbling Vireo Vireo gilvus 0 0 Western Scrub-jay Aphelocoma californica 0 Common Raven Corvus corax 2 1 2 2 Horned Lark Eremophila alpestris 0 0 0 2 0 Tree Swallow Tachycineta bicolor 0 0 Violet-green Swallow Tachycineta thalassina 0 0 Northern Rough-winged Swallow Stelgidopteryx serripennis 2 2 2 2 2 Cliff Swallow Petrochelidon pyrrhonata 0 0 0 0

49 Appendix C. List of all bird species detected at all sites using all methods in Riverside County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. RIMOWI= Riverside Mountains Wilderness; BIGWAS= Big Wash; SLTRWA= Slaughter Tree Wash; MCCWAS= McCoy Wash; SALCRE= Salt Creek; RECLWA= Red Cloud Wash. Sites are situated in Sonoran Desert Xeric Woodland. Common Name Scientific Name RIMOWI BIGWAS SLTRWA MCCWAS SALCRE RECLWA Barn Swallow Hirundo rustica 0 0 Verdin Auriparus flaviceps 1 2 1 1 1 1 Cactus Wren Campylorhynchus brunneicapillus 3 0 3 2 Rock Wren Salpinctes obsoletus 2 2 2 3 3 Bewick's Wren Thryomanes bewickii 0 House Wren Troglodytes aedon 0 0 0 Blue-gray Gnatcatcher Polioptila caerulea 0 0 0 0 Black-tailed Gnatcatcher Polioptila melanura 1 3 3 1 1 1 Ruby-crowned Kinglet Regulus calendula 0 0 0 0 Townsend's Solitaire Myadestes townsendi 0 Hermit Thrush Catharus guttatus 0 0 0 0 Northern Mockingbird Mimus polyglottos 1 3 2 2 1 Sage Thrasher Oreoscoptes montanus 0 0 0 0 Bendire's Thrasher Toxostoma bendirei 2 Crissal Thrasher Toxostoma crissale 2 1 2 LeConte's Thrasher Toxostoma lecontei 1 Phainopepla Phainopepla nitens 2 0 3 1 1 1 Orange-crowned Warbler Oreothlypis celata 0 0 0 0 0 Lucy's Warbler Oreothlypis luciae 1 1 3 3 Nashville Warbler Oreothlypis ruficapilla 0 0 0 Virginia's Warbler Oreothlypis virginiae 0 0 Yellow Warbler Setophaga petechia 0 0 0 0 MacGillivray's Warbler Geothlypis tolmiei 0 0 0 0 Common Yellowthroat Geothlypis trichas 0 Yellow-rumped (Audubon's) Warbler Setophaga coronata 0 0 0 0 0 0 Yellow-rumped (Myrtle) Warbler Setophaga coronata 0 0 Black-throated Gray Warbler Setophaga nigrescens 0 0 Townsend's Warbler Setophaga townsendi 0 0 Wilson's Warbler Wilsonia pusilla 0 0 0 0 Green-tailed Towhee Pipilo chlorurus 0 0 0 Spotted Towhee Pipilo maculatus 0 0 Abert's Towhee Melozone aberti 0 Chipping Sparrow Spizella passerina 0 0 0 Brewer's Sparrow Spizella breweri 0 0 0 0 0 0 Vesper Sparrow Pooecetes gramineus 0 Lark Sparrow Chondestes grammacus 0 Black-throated Sparrow Amphispiza bilineata 3 1 3 1 Sage Sparrow Amphispiza belli 0 Savannah Sparrow Passerculus sandwichensis 0 Lincoln's Sparrow Melospiza lincolnii 0 0 0 (Gambel's) White-crowned Sparrow Zonotrichia leucophrys 0 0 0 0 Western Tanager Piranga ludoviciana 0 0 0 0 Black-headed Grosbeak Peucticus melanocephalus 0 Lazuli Bunting Passerina amoena 0 0 0 0 Red-winged Blackbird Agelaius phoeniceus 0 0 Western Meadowlark Sturnella neglecta 0 2 Yellow-headed Blackbird Xanthocephalus xanthocephalus 0 0 Great-tailed Grackle Quiscalus mexicanus 0 Brown-headed Cowbird Molothrus ater 2 2 3 2 2

50 Appendix C. List of all bird species detected at all sites using all methods in Riverside County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. RIMOWI= Riverside Mountains Wilderness; BIGWAS= Big Wash; SLTRWA= Slaughter Tree Wash; MCCWAS= McCoy Wash; SALCRE= Salt Creek; RECLWA= Red Cloud Wash. Sites are situated in Sonoran Desert Xeric Woodland. Common Name Scientific Name RIMOWI BIGWAS SLTRWA MCCWAS SALCRE RECLWA Hooded Oriole Icterus cucullatus 0 0 0 Bullock's Oriole Icterus bullockii 2 2 0 2 Scott's Oriole Icterus parisorum 0 House Finch Carpodacus mexicanus 2 2 2 3 1 1 Lesser Goldfinch Spinus psaltria 0 2 2 2 Lawrence's Goldfinch Spinus lawrencei 1

51 Appendix C. List of all bird species detected at all sites using all methods in Riverside County, California, 2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. CORSPR = Corn Spring; NOPAMC=North of Palen-McCoy Wilderness; PAMCWI=Palen-McCoy Wilderness; CHUTHI=Chuckwalla Thicket . Common Name Scientific Name CORSPR NOPAMC PAMCWI CHUTHI Gambel's Quail Callipepla gambelii 3 3 3 3 Turkey Vulture Cathartes aura 2 2 2 2 Osprey Pandion haliaetus 0 Cooper's Hawk Accipiter cooperii 0 0 Red-tailed Hawk Buteo jamaicensis 2 2 2 1 Eurasian Collared-Dove Streptopelia decaocto 2 3 White-winged Dove Zenaida asiatica 3 2 2 2 Mourning Dove Zenaida macroura 3 3 3 3 Greater Roadrunner Geococcyx californicus 3 2 3 Barn Owl Tyto alba 0 Western Screech-Owl Megascops kennicottii 3 Great-horned Owl Bubo virginianus 3 2 Elf Owl Micathene whitneyi 3 Common Poorwill Phalaenoptilus nuttalli 2 2 Vaux's Swift Chaetura vauxi 0 0 White-throated Swift Aeronautes saxatalis 2 2 Black-chinned Hummingbird Archilochus alexandri 0 Costa's Hummingbird Calypte costae 3 3 3 Gila Woodpecker Melanerpes uropygialis 2 Ladder-backed Woodpecker Picoides scalaris 3 1 3 American Kestrel Falco sparverius 2 2 2 Prairie Falcon Falco mexicanus 2 Olive-sided Flycatcher Contopus cooperi 0 Hammond's Flycatcher Empidonax hammondii 0 0 Gray Flycatcher Empidonax wrightii 0 0 0 Western Flycatcher Empidonax difficilis 0 0 0 0 Say's Phoebe Sayornis saya 3 0 Ash-throated Flycatcher Myiarchus cinerascens 3 1 3 1 Western Kingbird Tyrannus verticalis 2 2 2 2 Loggerhead Shrike Lanius ludovicianus 3 3 3 3 Cassin's Vireo Vireo cassini 0 Warbling Vireo Vireo gilvus 0 0 0 Common Raven Corvus corax 3 2 2 3 Horned Lark Eremophila alpestris 0 2 Northern Rough-winged Swallow Stelgidopteryx serripennis 2 Tree Swallow Tachycineta bicolor 0 0 0 Violet-green Swallow Tachycineta thalassina 0 0 Bank Swallow Riparia riparia 0 Cliff Swallow Petrochelidon pyrrhonata 0 0 0 Barn Swallow Hirundo rustica 0 0 0 Verdin Auriparus flaviceps 1 1 1 3 Rock Wren Salpinctes obsoletus 3 2 Canyon Wren Catherpes mexicanus 3 Bewick's Wren Thryomanes bewickii 0 House Wren Troglodytes aedon 0 0 Cactus Wren Campylorhynchus brunneicapillus 1 3 2 2 Blue-gray Gnatcatcher Polioptila caerulea 0 0 0 Black-tailed Gnatcatcher Polioptila melanura 1 1 1 1 Swainson’s Thrush Catharus ustulatus 0 Hermit Thrush Catharus guttatus 0

52 Appendix C. List of all bird species detected at all sites using all methods in Riverside County, California, 2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. CORSPR = Corn Spring; NOPAMC=North of Palen-McCoy Wilderness; PAMCWI=Palen-McCoy Wilderness; CHUTHI=Chuckwalla Thicket . Common Name Scientific Name CORSPR NOPAMC PAMCWI CHUTHI Northern Mockingbird Mimus polyglottos 2 2 2 Curve-billed Thrasher Toxostoma curvirostre 2 Crissal Thrasher Toxostoma crissale 1 3 Le Conte’s Thrasher Toxostoma lecontei 1 Phainopepla Phainopepla nitens 1 2 2 2 Orange-crowned Warbler Oreothlypis celata 0 0 0 0 Lucy's Warbler Oreothlypis luciae 2 2 Nashville Warbler Oreothlypis ruficapilla 0 0 0 0 MacGillivray's Warbler Geothlypis tolmiei 0 0 0 Common Yellowthroat Geothlypis trichas 0 0 Yellow Warbler Setophaga petechia 0 0 0 Yellow-rumped (Audubon's)Warbler Setophaga coronata 0 0 0 0 Black-throated Gray Warbler Setophaga nigrescens 0 0 0 Townsend’s Warbler Setophaga townsendi 0 Hermit Warbler Setophaga occidentalis 0 0 Wilson's Warbler Cardellina pusilla 0 0 0 0 Green-tailed Towhee Pipilo chlorurus 0 0 Abert's Towhee Melozone aberti 2 Chipping Sparrow Spizella passerina 0 0 0 Brewer's Sparrow Spizella breweri 0 0 0 0 Black-throated Sparrow Amphispiza bilineata 1 2 2 3 (Gambel's) White-crowned Sparrow Zonotrichia leucophrys 0 0 0 0 (Mountain) White-crowned Sparrow Zonotrichia leucophrys 0 0 Pyrrhuloxia Cardinalis sinuatus 0 0 Western Tanager Piranga ludoviciana 0 0 Black-headed Grosbeak Pheucticus melanocephalus 0 0 0 Lazuli Bunting Passerina amoena 0 0 0 0 Red-winged Blackbird Agelaius phoeniceus 0 Brown-headed Cowbird Molothrus ater 2 3 3 2 Hooded Oriole Icterus cucullatus 2 0 0 Bullock's Oriole Icterus bullockii 0 0 0 Scott’s Oriole Icterus parisorum 2 0 House Finch Carpodacus mexicanus 3 3 2 3 Lesser Goldfinch Spinus psaltria 2 2

53 Appendix C. List of all bird species detected at all sites using all methods in Imperial County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. PVMOWI= Palo Verde Mountains Wilderness; MILWAS= Milpitas Wash; PICWAS= Picacho Wash; UNNWAS= Unnamed Wash; LIPIWI= Little Picacho Wilderness. Sites are situated in Sonoran Desert Xeric Woodland, though Little Picacho Wilderness also includes Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name PVMOWI MILWAS PICWAS UNNWAS LIPIWI Mallard Anas platyrhynchos 0 Gambel's Quail Callipepla gambelii 3 1 3 3 3 Pied-billed Grebe Podilymbus podiceps 2 Western Grebe Aechmophorus occidentalis 2 Great Egret Ardea alba 0 Turkey Vulture Cathartes aura 2 2 2 2 0 Osprey Pandion haliaetus 0 0 Northern Harrier Circus cyaneus 0 Sharp-shinned Hawk Accipiter striatus 0 0 0 Cooper's Hawk Accipiter cooperii 3 0 0 Red-tailed Hawk Buteo jamaicensis 2 1 2 2 Common Gallinule Gallinula galeata 2 American Coot Fulica americana 2 Wilson's Snipe Gallinago delicata 0 Eurasian Collared-dove Streptopelia decaocto 2 0 White-winged Dove Zenaida asiatica 2 3 2 2 2 Mourning Dove Zenaida macroura 3 1 1 1 1 Greater Roadrunner Geococcyx californicus 2 2 1 Western Screech-owl Megascops kennicottii 3 2 2 2 Great-horned Owl Bubo virginianus 2 2 2 Long-eared Owl Asio otus 0 1 2 Lesser Nighthawk Chordeiles acutipennis 2 1 2 3 2 Common Poorwill Phalaenoptilus nuttalli 2 0 0 Vaux's Swift Chaetura vauxi 0 0 0 0 White-throated Swift Aeronautes saxatalis 0 0 1 2 Black-chinned Hummingbird Archilochus alexandri 2 2 Anna's Hummingbird Calypte anna 2 1 2 Costa's Hummingbird Calypte costae 1 2 3 1 3 Rufous Hummingbird Selasphorus rufus 0 0 Calliope Hummingbird Selasphorus calliope 0 Gila Woodpecker Melanerpes uropygialis 2 1 2 3 Ladder-backed Woodpecker Picoides scalaris 2 1 3 3 3 American Kestrel Falco sparverius 2 2 2 2 Peregrine Falcon Falco peregrinus 0 Prairie Falcon Falco mexicanus 0 0 0 Olive-sided Flycatcher Comtopus cooperi 0 Western Wood-pewee Contopus sordidulus 0 Willow Flycatcher Empidonax traillii 0 Hammond's Flycatcher Empidonax hammondii 0 Gray Flycatcher Empidonax wrightii 0 0 0 0 Dusky Flycatcher Empidonax olberholserii 0 Western Flycatcher Empidonax difficilis 0 0 0 0 0 Black Phoebe Sayornis nigricans 0 0 0 0 0 Say's Phoebe Sayornis saya 2 2 3 2 Ash-throated Flycatcher Myiarchus cinerascens 1 1 1 1 3 Western Kingbird Tyrannus verticalis 0 3 2 2 2 Loggerhead Shrike Lanius ludovicianus 2 1 3 1 3 Bell's Vireo Vireo bellii 2 0 Gray Vireo Vireo vicinoir 0

54 Appendix C. List of all bird species detected at all sites using all methods in Imperial County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. PVMOWI= Palo Verde Mountains Wilderness; MILWAS= Milpitas Wash; PICWAS= Picacho Wash; UNNWAS= Unnamed Wash; LIPIWI= Little Picacho Wilderness. Sites are situated in Sonoran Desert Xeric Woodland, though Little Picacho Wilderness also includes Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name PVMOWI MILWAS PICWAS UNNWAS LIPIWI Cassin's Vireo Vireo cassinii 0 0 Warbling Vireo Vireo gilvus 0 0 0 0 Western Scrub-jay Aphelocoma californica 0 0 Common Raven Corvus corax 2 2 3 2 2 Horned Lark Eremophila alpestris 2 0 0 0 2 Tree Swallow Tachycineta bicolor 0 0 0 Violet-green Swallow Tachycineta thalassina 0 0 0 Northern Rough-winged Swallow Stelgidopteryx serripennis 3 1 1 3 Bank Swallow Riparia riparia 0 Cliff Swallow Petrochelidon pyrrhonata 0 0 0 0 Barn Swallow Hirundo rustica 0 0 0 0 Verdin Auriparus flaviceps 1 1 1 3 1 Cactus Wren Campylorhynchus brunneicapillus 0 1 2 1 Rock Wren Salpinctes obsoletus 2 1 3 2 Bewick's Wren Thryomanes bewickii 0 0 0 2 House Wren Troglodytes aedon 0 0 0 Marsh Wren Cistothorus palustris 2 Blue-gray Gnatcatcher Polioptila caerulea 0 0 0 0 Black-tailed Gnatcatcher Polioptila melanura 1 1 1 1 1 Ruby-crowned Kinglet Regulus calendula 0 0 0 0 Swainson’s Thrush Catharus ustulatus 0 Hermit Thrush Catharus guttatus 0 Northern Mockingbird Mimus polyglottos 3 1 1 2 3 Sage Thrasher Oreoscoptes montanus 0 0 0 0 0 Bendire's Thrasher Toxostoma bendirei 2 Crissal Thrasher Toxostoma crissale 2 1 2 2 American Pipit Anthus rubescens 0 0 Cedar Waxwing Bombycilla cedrorum 0 0 Phainopepla Phainopepla nitens 1 1 1 1 1 Orange-crowned Warbler Oreothlypis celata 0 0 0 0 0 Lucy's Warbler Oreothlypis luciae 1 2 3 Nashville Warbler Oreothlypis ruficapilla 0 0 0 0 0 MacGillivray's Warbler Geothlypis tolmiei 0 0 0 Common Yellowthroat Geothlypis trichas 0 0 3 Yellow Warbler Setophaga petechia 0 0 0 0 Yellow-rumped (Audubon's) Warbler Setophaga coronata 0 0 0 0 0 Black-throated Gray Warbler Setophaga nigrescens 0 0 0 0 Townsend's Warbler Setophaga townsendi 0 0 0 0 Hermit Warbler Setophaga occidentalis 0 Wilson's Warbler Cardellina pusilla 0 0 0 0 0 Yellow-breasted Chat Icteria virens 2 Green-tailed Towhee Pipilo chlorurus 0 Spotted Towhee Pipilo maculatus 0 Abert's Towhee Melozone aberti 2 2 Chipping Sparrow Spizella passerina 0 0 Brewer's Sparrow Spizella breweri 0 0 0 0 0 Black-chinned Sparrow Spizella atrogularis 0 Vesper Sparrow Pooecetes gramineus 0 Lark Sparrow Chondestes grammacus 0

55 Appendix C. List of all bird species detected at all sites using all methods in Imperial County, California, 2003-2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. PVMOWI= Palo Verde Mountains Wilderness; MILWAS= Milpitas Wash; PICWAS= Picacho Wash; UNNWAS= Unnamed Wash; LIPIWI= Little Picacho Wilderness. Sites are situated in Sonoran Desert Xeric Woodland, though Little Picacho Wilderness also includes Xeric Woodland/tamarisk interface at the Colorado River. Common Name Scientific Name PVMOWI MILWAS PICWAS UNNWAS LIPIWI Black-throated Sparrow Amphispiza bilineata 1 1 3 0 2 Song Sparrow Melospiza melodia 2 Lincoln's Sparrow Melospiza lincolnii 0 0 (Gambel's) White-crowned Sparrow Zonotrichia leucophrys 0 0 0 0 (Mountain) White-crowned Sparrow Zonotrichia leucophrys 0 Dark-eyed (Oregon) Junco Junco hyemalis 0 Dark-eyed (Slate-colored) Junco Junco hyemalis 0 Western Tanager Piranga ludoviciana 0 0 0 0 Black-headed Grosbeak Pheuticus melanocephalus 0 Lazuli Bunting Passerina amoena 0 0 0 Red-winged Blackbird Agelaius phoeniceus 0 0 0 Western Meadowlark Sturnella neglecta 2 2 2 Yellow-headed Blackbird Xanthocephalus xanthocephalus 0 0 Brewer's Blackbird Euphagus cyanocephalus 0 Great-tailed Grackle Quiscalus mexicanus 0 3 Brown-headed Cowbird Molothrus ater 2 3 3 3 2 Hooded Oriole Icterus cucullatus 0 0 0 Bullock's Oriole Icterus bullockii 2 2 2 2 2 Scott's Oriole Icterus parisorum 0 House Finch Carpodacus mexicanus 2 1 1 1 1 Lesser Goldfinch Spinus psaltria 2 2 2 Lawrence's Goldfinch Spinus lawrencei 0 2 2 House Sparrow Passer domesticus 0 0

56 Appendix C. List of all bird species detected at Mojave Wilderness sites sites using all methods in San Bernardino County, California, 2012. Species with confirmed breeding highlighted and in bold type. Confirmed breeding = 1; Probable breeding = 3; Possible breeding = 2; Observed but with no evidence of breeding = 0. NOMEWI= North Mesquite Mountains Wilderness; EAMEWI= East Mesquite Wilderness; STATWI= Stateline Wilderness; KIRAWI= Kingston Range Wilderness; MESQWI = Mesquite Wilderness. . Common Name Scientific Name NOMEWI EAMEWI STATWI KIRAWI MESQWI Gambel's Quail Callipepla gambelii 2 2 2 Chukar Alectoris chukar 2 Turkey Vulture Cathartes aura 2 2 Golden Eagle Aquila chrysaetos 2 Red-tailed Hawk Buteo jamaicensis 2 2 2 Rock Pigeon Columba livia 0 Mourning Dove Zenaida macroura 2 2 Common Ground-dove Columbina passerina 2 Greater Roadrunner Geococcyx californicus 3 3 3 3 Lesser Nighthawk Chordeiles acutipennis 2 White-throated Swift Aeronautes saxatalis 0 Costa's Hummingbird Calypte costae 2 Ladder-backed Woodpecker Picoides scalaris 3 2 3 3 Gilded Flicker Colaptes chrysoides 2 American Kestrel Falco sparverius 3 3 Gray Flycatcher Empidonax wrightii 0 Say's Phoebe Sayornis saya 2 3 2 Ash-throated Flycatcher Myiarchus cinerascens 2 3 3 3 Western Kingbird Tyrannus verticalis 2 Loggerhead Shrike Lanius ludovicianus 3 3 Common Raven Corvus corax 2 2 2 2 2 Horned Lark Eremophila alpestris 2 2 Tree Swallow Tachycineta bicolor 0 0 Northern Rough-winged Swallow Stelgidopteryx serripennis 0 Cliff Swallow Petrochelidon pyrrhonata 0 Verdin Auriparus flaviceps 2 2 Cactus Wren Campylorhynchus brunneicapillus 3 3 3 3 Blue-gray Gnatcatcher Polioptila caerulea 0 Black-tailed Gnatcatcher Polioptila melanura 2 3 2 2 Northern Mockingbird Mimus polyglottos 2 Le Conte’s Thrasher Toxostoma lecontei 3 3 3 3 Phainopepla Phainopepla nitens 2 2 Common Yellowthroat Geothlypis trichas 0 Yellow-rumped (Audubon's) Warbler Setophaga coronata 0 Black-throated Gray Warbler Setophaga nigrescens 0 Wilson's Warbler Cardellina pusilla 0 Chipping Sparrow Spizella passerina 0 Brewer's Sparrow Spizella breweri 0 0 0 Black-chinned Sparrow Spizella atrogularis Black-throated Sparrow Amphispiza bilineata 3 3 3 3 (Gambel's) White-crowned Sparrow Zonotrichia leucophrys 0 (Mountain) White-crowned Sparrow Zonotrichia leucophrys 0 Black-headed Grosbeak Peucticus melanocephalus 0 Western Tanager Piranga ludoviciana 0 Scott's Oriole Icterus parisorum 2 3 House Finch Carpodacus mexicanus 2 2 2 2 Lesser Goldfinch Spinus psaltria 0

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