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Spokane Valley, WA, United States

Stonehouse K.F.,Washington State University | Shipley L.A.,Washington State University | Lowe J.,Bureau of Land Management | Atamian M.T.,315 North Discovery Place | Swanson M.E.,Washington State University
Journal of Wildlife Management | Year: 2015

Greater sage-grouse (Centrocercus urophasianus) and Columbian sharp-tailed grouse (Tympanuchus phasianellus columbianus) have declined substantially in Washington, USA, primarily because native shrub-steppe has been converted to agriculture. In response, state and federal agencies have acquired and restored habitat, and augmented and reintroduced grouse to suitable areas. We examined how sympatric, translocated sage-grouse and sharp-tailed grouse used space and selected habitats within their spring-summer home ranges and at nest sites within remnant shrub-steppe surrounded by a matrix of cropland in eastern Washington. Because their life-history requirements differ, we expected extensive habitat partitioning between species. Using radiolocations of ≥43 birds of each species, we found that sage-grouse had larger spring-summer home ranges than sharp-tailed grouse, and the composite of home ranges for sharp-tailed grouse fell almost completely within the composite of home ranges for sage-grouse. By creating resource utilization function models using radiolocations of ≥53 birds of each species, we found that areas of highest predicted intensity of use for both species overlapped by >50%, even at the top 5% quantile. Both species used restored fields and areas farther from trees and roads or distribution lines more intensely. Sage-grouse used less rugged areas more intensely, and both species used 3 levels of shrub cover equally. To compare selection of nest sites relative to available sites for nesting in both species, we created resource selection function models for ≥30 birds of each species and found that sage-grouse selected areas farther from distribution lines, whereas sharp-tailed grouse selected restored fields. When we examined vegetation characteristics used by female sage-grouse and sharp-tailed grouse at nest sites using a case-control, use versus non-use design for ≥26 birds of each species, we found sage-grouse used areas with greater shrub cover, lower annual forb cover, and taller perennial grasses, whereas sharp-tailed grouse used areas with greater perennial grass cover and taller perennial grasses and forbs. When we compared habitat features measured at nest sites between species, we found sage-grouse used areas with greater moderate and dense shrub cover, lower sparse shrub cover, less restored fields, higher patch diversity, and areas farther from distribution lines than sharp-tailed grouse. These differences resulted in only 38% overlap of areas within the top quartile of relative selection values for nest sites by the 2 species, and <10% at the top 5% quantile. Because many western states are highly fragmented by cropland, understanding how populations of species with different life-history characteristics, such as sage-grouse and sharp-tailed grouse, coexist within remaining tracts of shrub-steppe at different spatial scales is important for effectively conserving and managing shrub-steppe communities. © 2015 The Wildlife Society. Source

Mccorquodale S.M.,701 So. 24th Ave. | Wik P.A.,315 North Discovery Place | Fowler P.E.,315 North Discovery Place
Journal of Wildlife Management | Year: 2011

We studied survival of elk (Cervus elaphus) ≥1 yr old and quantified mortality sources in the Blue Mountains of Washington, 2003-2006, following a period of extensive poaching. The population was managed under a spike-only general hunting season, with limited permits for larger males and for females. We radiomarked 190 elk (82 males and 39 females >1 yr old and 65 males 11 months old), most with rumen transmitters and neck radiocollars; 60 elk only received rumen transmitters. We estimated annual survival using known fate models and explored survival differences among sex and age classes and in 2 potentially different vulnerability zones for males. We found little support for differences in survival between younger (2-3-yr old) and older (≥4-yr old) branch-antlered males or zone differences for yearling males. A model with zone differences for branch-antlered males was the second ranked model and accounted for 14% of the available model weight. From the best-supported models, we estimated annual survival for yearling males at 0.41 (95% CI: 0.29-0.53). We estimated pooled adult female survival at 0.80 (95% CI: 0.64-0.93); when an age-class effect was included, point estimates were higher for prime-aged females (2-11 yr: S = 0.81 [0.70-0.88]) than for older females (≥12 yr: S = 0.72 [0.56-0.83]), but confidence intervals broadly overlapped. Only 1 of 7 models with a female age effect on survival was among the competitive models. For branch-antlered males, survival ranged 0.80-0.85, depending on whether zone variation was modeled.We recorded 78 deaths of radiomarked elk. Human-caused deaths (n = 55) predominated among causes and most were of yearling males killed during state-sanctioned hunts (n = 28). Most subadult male deaths were from tribal hunting (n = 5), and most mature males died from natural causes (n = 6) and tribal hunting (n = 5). We detected few illegal kills (n = 4). Our results suggest that increased enforcement effectively reduced poaching, that unreported tribal harvest was not a trivial source of mortality, and that spike-only general seasons were effective in recruiting branch-antlered males. © 2011 The Wildlife Society. Source

Shanthalingam S.,Washington State University | Goldy A.,Washington State University | Bavananthasivam J.,Washington State University | Subramaniam R.,Washington State University | And 13 more authors.
Journal of Wildlife Diseases | Year: 2014

Mannheimia haemolytica consistently causes severe bronchopneumonia and rapid death of bighorn sheep (Ovis canadensis) under experimental conditions. However, Bibersteinia trehalosi and Pasteurella multocida have been isolated from pneumonic bighorn lung tissues more frequently than M. haemolytica by culture-based methods. We hypothesized that assays more sensitive than culture would detect M. haemolytica in pneumonic lung tissues more accurately. Therefore, our first objective was to develop a PCR assay specific for M. haemolytica and use it to determine if this organism was present in the pneumonic lungs of bighorns during the 2009-2010 outbreaks in Montana, Nevada, and Washington, USA. Mannheimia haemolytica was detected by the species-specific PCR assay in 77% of archived pneumonic lung tissues that were negative by culture. Leukotoxin-negative M. haemolytica does not cause fatal pneumonia in bighorns. Therefore, our second objective was to determine if the leukotoxin gene was also present in the lung tissues as a means of determining the leukotoxicity of M. haemolytica that were present in the lungs. The leukotoxin-specific PCR assay detected leukotoxin gene in 91%of lung tissues that were negative for M. haemolytica by culture. Mycoplasma ovipneumoniae, an organism associated with bighorn pneumonia, was detected in 65%of pneumonic bighorn lung tissues by PCR or culture. A PCR assessment of distribution of these pathogens in the nasopharynx of healthy bighorns from populations that did not experience an all-age die-off in the past 20 yr revealed that M. ovipneumoniae was present in 31%of the animals whereas leukotoxin-positive M. haemolytica was present in only 4%. Taken together, these results indicate that culture-based methods are not reliable for detection of M. haemolytica and that leukotoxin-positive M. haemolytica was a predominant etiologic agent of the pneumonia outbreaks of 2009-2010. © Wildlife Disease Association 2014. Source

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