Washington Ground Squirrel Surveys in Adams, Douglas, and Grant Counties, Washington, 2004 We surveyed a total of 303 Washington ground squirrel sites from late March to early June 2004 and confirmed occupancy at 218 of 247 (88%) sites that were classified as occupied during surveys conducted from 2001-2003. Occupancy rates for subregions of Washington ground squirrel sites typically exceeded 85%. However, the Seep Lakes Area in Grant County, the Hatton Area in Adams County, and the Foster Coulee Area in Douglas County each showed declines of =35% in occupancy rates from 2001-2003 to 2004. The reduction in the Seep Lakes Area exceeded the findings of Dr. Paul Sherman, who observed a 17% decline in active sites in this area from 1999 to 2001. The Black Rock Coulee and Sagebrush Flats Areas in Grant County experienced 15% and 11% declines in active sites from 2001-2003 to 2004, respectively. Nine previously undocumented sites were discovered in 2004.

Eastern Washington Ground Squirrel Placemat [PDF Format 3.62 MB] Placemat with Activities

Fragmention by Agriculture Influences Reproductive Success of Birds in a Shrubsteppe Landscape Shrubsteppe communities are among the most imperiled ecosystems in North America as a result of conversion to agriculture and other anthropogenic changes. In the Intermountain West of the United States, these communities support a unique avifauna, including several species that are declining and numerous others that are of conservation concern. Extensive research in the eastern and central United States and in Scandinavia suggests that fragmentation of formerly continuous forests and grasslands adversely affects reproductive success of birds, yet little is known of the potential effects on avian communities in Western shrublands. I used multi-model inference to evaluate the potential effects of local and landscape variables on nest predation and brood parasitism, and behavioral observations of color-banded birds to evaluate the potential effects of habitat fragmentation on seasonal reproductive success of passerines in the shrubsteppe of eastern Washington State, USA.

Male Incubation and Multiple Brooding in Sagebrush Brewer’s Sparrows We report on the incidence of male incubation and multiple brooding in Sagebrush Brewer’s Sparrows (Spizella breweri breweri) at the northwestern limit of their breeding range in southern British Columbia, 1998–2000, and in central Washington, 1996–1999. Males frequently incubated eggs, accounting for 28% of 329 observations of incubation by known individuals in British Columbia. In Washington, 51% of the males we monitored incubated eggs. Males and females appeared equally able to increase nest temperature. In British Columbia, 17% of females fledged two broods per season, and two females fledged three broods. In Washington, 5% of males fledged two broods per season. Only one previous case of male incubation has been reported in this species and multiple brooding has been poorly documented. These aspects of the breeding biology of other wellstudied species may be underestimated without the careful examination of populations of marked individuals.

Parasitism by Brown-Headed Cowbirds in the Shrubsteppe of Eastern Washington Shrubsteppe communities within the Intermountain West have been reduced in area and fragmented by agricultural conversion and land development, yet we know little about the effects of Brown-headed Cowbirds (Molothrus ater) on reproductive success of birds that breed in these communities. As part of ongoing research examining landscape effects on avian productivity in eastern Washington, we collected data on parasitism rates and cowbird occurrence. During 1996 and 1997 we surveyed birds using point-counts and searched for nests in big sagebrush (Artemisia tridentata) stands in eastern Washington. Cowbirds were common on our study area and were recorded on point-counts at 26 of 29 sites surveyed. Cowbirds arrived on the study area in late April, attaining greatest abundance in May and June. We located and monitored a total of 779 nests of 8 species; only the Brewer's Sparrow (Spizella breweri), Sage Sparrow (Amphispiza belli), and Vesper Sparrow (Pooecetes gramineus) showed evidence of parasitism. Overall parasitism rates were lower than those reported for other bird communities in fragmented landscapes and for other bird communities in shrubsteppe. Low parasitism levels (<10 %) in our study area partly resulted from arrival of cowbirds after initiation of first nests by hosts. Over 40% of Sage Sparrow nests were initiated before cowbirds were observed laying on the study area. Low levels of parasitism also may be related to low availability of elevated observation perches or long distances from study plots to cowbird feeding areas. Determining why parasitism is low in this fragmented landscape may have important implications for managing cowbirds in other areas.

Predation on Real and Artificial Nests in Shrubsteppe Landscapes Fragmented by Agriculture Clearing of shrubsteppe communities for agriculture has created a highly fragmented landscape in eastern Washington, a condition that has been shown to adversely affect nesting success of birds in some forest and grassland communities.We used artificial nests monitored by cameras to examine relative effects of fragmentation, distance to edge, and vegetation cover on nest predation rates and to identify predators of shrubsteppenesting passerines and grouse. Predation rate for artificial nests was 26% (n = 118). Fragmentation had a strong influence on predation rates for artificial nests, with nests in fragmented landscapes about 9 times more likely to be depredated as those in continuous landscapes. Daily survival rate (± SE) for 207 real nests of 4 passerine species also was greater in continuous (0.978 ± 0.004) than in fragmented (0.962 ± 0.006) landscapes, although pattern of predation between real and artificial nests was not consistent among sites. Artificial nests were depredated by Common Ravens (Corvus corax), Black-billed Magpies (Pica hudsonia), Sage Thrashers (Oreoscoptes montanus), least chipmunks (Tamias minimus), and mice. Most nests in fragments were depredated by corvids (58%), whereas only Sage Thrashers and small mammals depredated nests in continuous landscapes. Increased predation by corvids and lower nest success in fragmented landscapes may have played a part in recent declines of some shrubsteppe birds. Future research should measure annual reproductive success of individual females and survival rates of juveniles and adults.

Shrubsteppe Bird Response to Habitat and Landscape Variables in Eastern Washington, USA The landscape of the intermountain west has changed dramatically in the last 150 years, particularly in the state of Washington where over half the native shrubsteppe ecosystem has been converted to agricultural lands resulting in a fragmented landscape with few extensive tracts of shrubsteppe. We examined the historical and current distribution of shrubsteppe on different soil types in eastern Washington and we surveyed bird communities at 78 sites in shrubsteppe from 1991 to 1993. We compared abundance of species among soil types and range conditions and developed models of species occurrence using site-specific vegetation and landscape variables. The pattern of shrubsteppe conversion has resulted in a disproportionate loss of deep soil communities. Eight species showed strong relationships with soil type and three with range condition. These associations likely resulted from the influence of soil type and range history on the vegetation of these communities. Brewer's Sparrows (Spizella breweri) and Sage Sparrows (Amphispiza belli) reached their highest abundances in deep, loamy soils, whereas Loggerhead Shrikes (Lanius ludovicianus) were most abundant in deep, sandy soils. Sage Sparrows occurred more frequently in landscapes dominated by shrubsteppe, indicating a negative relationship with fragmentation. Our results suggest that fragmentation of shrubsteppe and the pattern of agricultural conversion among soil types have had detrimental effects on numerous shrubsteppe species. The landscape for species with an affinity for deep, loamy soil communities has changed considerably more than the overall loss of shrubsteppe would indicate. Conservation practices that emphasize retention of shrubsteppe communities on deep soils and that reduce further fragmentation will be critical to the maintenance of avian biological diversity in this system.

Shrubsteppe Mapping of Eastern Washington Using Landsat Satellite Thematic Mapper Data Shrubsteppe provides important habitat for many wildlife species in Washington State, such as the sage grouse (Centrocerus urophasianus), sharp-tailed grouse (Tympanuchus phasiannellus), and pygmy rabbit (Brachylagus idahoensis) which are currently listed as threatened or endangered with extinction. Shrubsteppe once extended over nearly all of the non-forested land in Washington east of the Cascade Mountain Range, but now only occupies about 50% of its historical range. The continuous loss of this important habitat makes it imperative the spatial distribution and characteristics of shrubsteppe be mapped for the effective conservation and management of obligate wildlife species. The wide distribution of shrubsteppe landcover throughout eastern Washington made the data obtained from the Thematic Mapper (TM) sensor onboard the Landsat 5 satellite platform a logical and cost-effective choice for this mapping project.

Status of Washington's Shrubsteppe Ecosystem: Extent, ownership, and wildlife/vegetation relationships (PDF Format - 2.4MB) Washington's shrubsteppe communities support a wide diversity of wildlife. Ninety-four species of birds were recorded on 55 transects surveyed over 3 years. The diversity of species encountered resulted both from the placement of transects across of range of shrubsteppe range sites, and the interspersion of other land-use types (e.g., agricultural fields, Conservation Reserve Program lands) among the remaining areas of shrubsteppe. The two most common species on the survey, western meadowlark and horned lark, are grassland birds that have adapted well to agriculture and also use shrubsteppe. Studies in more extensive areas of shrubsteppe have found sage sparrows or Brewer's sparrows (both shrubsteppe obligates) to be the most numerous species, perhaps reflecting a lower influence of agriculture in these other regions. Brewer's sparrows and sage sparrows ranked third and eighth in abundance in the Washington surveys.

Teetering on the Edge or Too Late? Conservation and Research Issues for Avifauna of Sagebrush Habitats Degradation, fragmentation, and loss of native sagebrush (Artemisia spp.) landscapes have imperiled these habitats and their associated avifauna. Historically, this vast piece of the Western landscape has been undervalued: even though more than 70% of all remaining sagebrush habitat in the United States is publicly owned, <3% of it is protected as federal reserves or national parks. We review the threats facing birds in sagebrush habitats to emphasize the urgency for conservation and research actions, and synthesize existing information that forms the foundation for recommended research directions. Management and conservation of birds in sagebrush habitats will require more research into four major topics: (1) identification of primary land-use practices and their influence on sagebrush habitats and birds, (2) better understanding of bird responses to habitat components and disturbance processes of sagebrush ecosystems, (3) improved hierarchical designs for surveying and monitoring programs, and (4) linking bird movements and population changes during migration and wintering periods to dynamics on the sagebrush breeding grounds. This research is essential because we already have seen that sagebrush habitats can be altered by land use, spread of invasive plants, and disrupted disturbance regimes beyond a threshold at which natural recovery is unlikely. Research on these issues should be instituted on lands managed by state or federal agencies because most lands still dominated by sagebrush are owned publicly. In addition to the challenge of understanding shrubsteppe bird-habitat dynamics, conservation of sagebrush landscapes depends on our ability to recognize and communicate their intrinsic value and on our resolve to conserve them.

Use of Conservation Reserve Program Fields by Greater Sage-Grouse and Other Shrubsteppe-associated Wildlife in Washington State The Conservation Reserve Program (CRP) is currently the largest-scale effort to restore grassland and shrubsteppe habitat in the Columbia River Basin. Administered by the Farm Service Agency (FSA) of the US Department of Agriculture, this voluntary program pays farmers to take agricultural lands out of production to achieve conservation objectives including reduced soil erosion and provision of wildlife habitat. In Washington, about 1.5 million acres (600,000 ha) of converted farmland has been planted to perennial grasses, forbs and shrubs under the CRP. Unlike CRP in the mid-west that largely occurs on land that was formerly prairie, much of the CRP in Washington occurs on land that was historically shrubsteppe. The current acreage of CRP land in eastern Washington is equal to about 10% of the state’s total agricultural lands.

Wildlife of Eastside Shrubland and Grassland Habitats The rain shadow of the Cascade Mountains gives rise to a suite of and and semi-arid habitats that differ substantially from those of the surrounding forest. O'Neil and Johnson have classified these habitats into 6 different types: shrub-steppe, dwarf shrubsteppe, desert playa and salt scrub, western juniper and mountain mahogany woodlands, eastside canyon shrublands, and eastside grasslands. Most of these communities are dominated by shrubs and herbaceous vegetation (grasses and forbs) and typically have a microbiotic crust of lichens and mosses binding the upper surface of the soil. With the exception of the western juniper and mountain mahogany woodlands habitat type, trees in these communities are limited mainly to riparian zones and ecotones with forested habitats and are entirely absent from extensive areas. Much of the historical vegetation in these habitat types, particularly in Washington and north central Oregon, has been converted to agricultural crops. In some areas, the only remaining native communities are on rocky soils or steep slopes unfit for agriculture. The dominant land use in these shrubland and grassland habitats is, livestock grazing, and few examples of undisturbed stands exist, limited primarily to sites where topography or remoteness from water has made access for livestock grazing impractical."

Wildlife on Conservation Reserve Program lands and native shrubsteppe in Washington Progress Report: 2004 The Conservation Reserve Program (CRP) is currently the only large-scale effort to restore habitat that may be used by grassland and shrubsteppe wildlife in the Columbia River Basin. Administered by the US Department of Agriculture, this voluntary program pays farmers to take agricultural lands out of production to achieve conservation objectives including reducing soil erosion and providing wildlife habitat. In Washington, over 1 million acres (405,000 ha) of converted farmland has been planted to non-native grasses and to native grasses, forbs and shrubs under the CRP. In 2003 we began a study to evaluate the potential role of CRP in the long-term conservation of obligate grassland and shrubsteppe wildlife in the Columbia River Basin. We established 48 study sites in CRP fields of varying age and landscape contexts and in extant shrubsteppe communities. In 2004, we repeated surveys of birds, herptiles, and small mammals and we examined reproductive parameters of selected bird species. In addition, we characterized the vegetation on all sites and we added two new components to the study: a survey of the mosses and lichens that make up the biological soil crusts and pellet surveys to document use by lagomorphs, deer, and prairie grouse. Plans for 2005 include continued bird and small mammal surveys, pellet sampling, and sampling of the remaining sites for biological soil crusts.

Contact wildthing@dfw.wa.gov for more information about research.