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Lewiston, ID, United States

Ausband D.E.,University of Montana | Mitchell M.S.,University of Montana | Doherty K.,University of Montana | Zager P.,316 16th Street | And 2 more authors.
Journal of Wildlife Management | Year: 2010

We used rendezvous site locations of wolf (Canis lupus) packs recorded during 19962006 to build a predictive model of gray wolf rendezvous site habitat in Idaho, USA. Variables in our best model included green leaf biomass (Normalized Difference Vegetation Index), surface roughness, and profile curvature, indicating that wolves consistently used wet meadow complexes for rendezvous sites. We then used this predictive model to stratify habitat and guide survey efforts designed to document wolf pack distribution and fecundity in 4 study areas in Idaho. We detected all 15 wolf packs (32 wolf pack-yr) and 20 out of 27 (74) litters of pups by surveying <11 of the total study area. In addition, we were able to obtain detailed observations on wolf packs (e.g., hair and scat samples) once we located their rendezvous sites. Given an expected decrease in the ability of managers to maintain radiocollar contact with all of the wolf packs in the northern Rocky Mountains, rendezvous sites predicted by our model can be the starting point and foundation for targeted sampling and future wolf population monitoring surveys. © 2010 The Wildlife Society. Source

Cossel Jr. J.O.,Northwest Nazarene University | Gaige M.G.,316 16th Street | Sauder J.D.,Northwest Nazarene University
Wildlife Society Bulletin | Year: 2012

Electroshocking has long been employed as a survey technique for fish, but has not been directly tested against rock rolling as a survey methodology for stream-dwelling amphibians. Electroshocking has the potential to reduce habitat disturbances that result from surveys, improve abundance estimates, and reduce injuries and effort in collecting data. Furthermore, accurately quantifying species and survey techniquespecific estimates of detection probabilities is critical for appropriately interpreting survey results and employing occupancy analyses. We tested the efficiency and sensitivity of rock rolling and electroshocking in detecting Idaho giant salamanders (Dicamptodon aterrimus) in a small stream in northern Idaho, USA, by sampling short (25 m) segments of a stream using both survey techniques. We also conducted multi-pass surveys of 400-m stream segments to estimate detection probabilities for D. aterrimus and Rocky Mountain tailed frog (Ascaphus montanus). Using electroshocking, we detected D. aterrimus 40% more often than by rock rolling and detected 3.5 times as many individuals, with substantially reduced effort. Using electroshocking, detection probabilities were 1.0 for D. aterrimus and 0.79 (95% CI = 0.63-0.88) for A. montanus. Our results show electroshocking to be a much more sensitive and efficient method of detecting streamdwelling amphibians than the traditional technique of rock rolling. Electroshocking can serve as an important survey technique for secretive stream-dwelling amphibians, allowing managers to quickly and safely acquire valuable data of better quality. © 2012 The Wildlife Society. Source

Weiser G.C.,University of Idaho | Drew M.L.,6569 South 10th Avenue | Frances Cassirer E.,316 16th Street | Ward A.C.S.,University of Idaho
Journal of Wildlife Diseases | Year: 2012

Mycoplasma species are of interest as possible primary pathogens in the pneumonia complex of bighorn sheep (Ovis canadensis). Previous investigations have not commonly detected low frequencies of Mycoplasma spp. from free-ranging bighorn sheep, possibly due to the fastidious and slow growth of these organisms. We developed a culture protocol that employed an average initial 3-day enrichment culture in liquid Hayflick broth in a CO 2- enhanced atmosphere. The broth was plated to solid Hayflick medium and the cultures observed for growth for up to 30 days. Polymerase chain reaction (PCR) was performed on DNA isolated from the enrichment broth and on isolates obtained from culture using Mycoplasma genus-specific PCR assays and speciesspecific PCR assays for M. arginini and M. ovipneumoniae. Some cultures that grew on Hayflick plates were picked as single colonies but were mixed because two organisms may grow together and appear as a single colony. Culture and PCR tests produced similar results for M. arginini, but for M. ovipneumoniae, culture alone was less accurate than PCR. Use of genus-specific primers also may allow detection of other species in samples negative for M. arginini and M. ovipneumoniae. Two methods of transport from field to laboratory (Port-a-Cul™ tubes, cryoprotectant in liquid N 2 and Fisher Transport System) gave similar results under our study conditions. © Wildlife Disease Association 2012. Source

Olson L.E.,Rocky Research | Sauder J.D.,316 16th Street | Albrecht N.M.,Wildlife Program | Vinkey R.S.,Montana Fish | And 2 more authors.
Biological Conservation | Year: 2014

Climate change impacts many species through shifts in habitat. The intensity of this impact will depend on the dispersal rates of the species, the patchiness of the environment, and the velocity of habitat change. Here we examine how dispersal affects projected future habitat availability for a threatened carnivore, the fisher (Pekania [. Martes] pennanti). We used non-invasive genetic sampling to detect fisher across their historical distribution in Montana and Idaho. This survey included 4846 non-invasive hair snares, of which 288 identified fishers through mitochondrial DNA analysis. We modeled the distribution of fisher across western Montana and northern Idaho using a suite of vegetative, topographic, and climatic variables. We modeled future distribution using a global climate model and two climate change scenarios (high emissions [A2] or reduced emissions [B2]) and three time steps (2030, 2060, and 2090). We incorporated the effects of dispersal ability and habitat patch size into our model by varying the distance and enforcing a minimum patch size at which newly created habitat could be colonized. We found that the probability of current fisher occurrence was highest given the presence of mesic forest types with tall trees, high annual precipitation, and mid-range winter temperatures. Future predictions show an increase in area of high-probability habitat under most dispersal assumptions. Interestingly, we found a large contrast in results when minimum patch size and species dispersal capabilities were considered. Our distribution model with full dispersal and no limits on patch size predicted a 24.5% increase in fisher habitat by 2090, whereas a dispersal limit of 1. km through non-habitat (agricultural fields and urban zones) and a minimum patch size yielded a loss of 25.8% of fisher habitat under this same scenario. Varying dispersal appears to limit habitat availability more than minimum patch size under most scenarios. © 2013. Source

Hurley M.A.,9 Highway 93 N | Zager P.,316 16th Street | Hebblewhite M.,University of Montana | Garton E.O.,University of Idaho | And 3 more authors.
Wildlife Monographs | Year: 2011

Manipulating predator populations is often posed as a solution to depressed ungulate populations. However, predator-prey dynamics are complex and the effect on prey populations is often an interaction of predator life history, climate, prey density, and habitat quality. The effect of predator removal on ungulate and, more specifically, mule deer (Odocoileus hemionus) populations has not been adequately investigated at a management scale. We tested the efficacy of removing coyotes (Canis latrans) and mountain lions (Puma concolor) for increasing survival and population growth rate of mule deer in southeastern Idaho, USA, during 1997-2003. We assigned 8 game management units (GMUs) to treatments under a 2 × 2 factorial design (treatments of coyote removal and lion removal) with 2 replicates of each treatment or reference area combination. We used methods typically available to wildlife managers to achieve predator removals and a combination of extensive and intensive monitoring in these 8 GMUs to test the hypothesis that predator removal increased vital rates and population growth rate of mule deer. We determined effects of predator removal on survival and causes of mortality in 2 intensive study sites, one with coyote and mountain lion removal and one without. We also considered the effects of other variables on survival including lagomorph abundance and climatic conditions. In these 2 intensive study areas, we monitored with radiotelemetry 250 neonates, 284 6-month-old fawns, and 521 adult females. At the extensive scale, we monitored mule deer population trend and December fawn ratios with helicopter surveys. Coyote removal decreased neonate mortality only when deer were apparently needed as alternate prey, thus removal was more effective when lagomorph populations were reduced. The best mortality model of mule deer captured at 6 months of age included summer precipitation, winter precipitation, fawn mass, and mountain lion removal. Over-winter mortality of adult female mule deer decreased with removal of mountain lions. Precipitation variables were included in most competing mortality models for all age classes of mule deer. Mountain lion removal increased fawn ratios and our models predicted fawn ratios would increase 6% at average removal rates (3.53/1,000 km 2) and 27% at maximum removal rates (14.18/1,000 km 2). Across our extensive set of 8 GMUs, coyote removal had no effect on December fawn ratios. We also detected no strong effect of coyote or mountain lion removal alone on mule deer population trend; the best population-growth-rate model included previous year's mountain lion removal and winter severity, yet explained only 27% of the variance in population growth rate. Winter severity in the current and previous winter was the most important influence on mule deer population growth. The lack of response in fawn ratio or mule deer abundance to coyote reduction at this extensive (landscape) scale suggests that decreased neonate mortality due to coyote removal is partially compensatory. Annual removal of coyotes was not an effectivemethod to increase mule deer populations in Idaho because coyote removal increased radiocollared neonate fawn survival only under particular combinations of prey densities and weather conditions, and the increase did not result in population growth. Coyote-removal programs targeted in areas where mortality of mule deer fawns is known to be additive and coyote-removal conditions are successful may influence mule deer population vital rates but likely will not change direction of population trend. Although mountain lion removal increased mule-deer survival and fawn ratios, we were unable to demonstrate significant changes in population trend with mountain lion removal. In conclusion, benefits of predator removal appear to be marginal and short term in southeastern Idaho and likely will not appreciably change long-term dynamics of mule deer populations in the intermountain west. © 2011 The Wildlife Society. Source

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