A5030701020- Wildlife Ecology and Conservation
- Rangeland and Wildlife Management
- Animal Behavior and Welfare Studies
- Veterinary Equine Medical Research
- Ecology and Vegetation Dynamics Studies
- Species Distribution and Climate Change
- Ecology and biodiversity studies
- Genetic and phenotypic traits in livestock
- Fire effects on ecosystems
- Rangeland Management and Livestock Ecology
- Reproductive Physiology in Livestock
- Genetic diversity and population structure
- Avian ecology and behavior
- Botany, Ecology, and Taxonomy Studies
- Archaeology and Natural History
- Ruminant Nutrition and Digestive Physiology
- Diet and metabolism studies
- Genetically Modified Organisms Research
- Human-Animal Interaction Studies
- Effects of Environmental Stressors on Livestock
- Agriculture and Farm Safety
- Economic and Environmental Valuation
- Geographies of human-animal interactions
- Soil and Water Nutrient Dynamics
- Mediterranean and Iberian flora and fauna
United States Geological Survey
2014-2024
Fort Collins Science Center
2014-2024
Colorado State University
2003-2024
Entertainment Industries Council
2015
Rocky Mountain Research Station
2011
University of Arizona
1997
ABSTRACT Demographic data show many populations of Rocky Mountain ( Cervus elaphus nelsoni ) and Roosevelt roosevelti elk have been declining over the last few decades. Recent work suggests that forage quality associated animal nutritional condition, particularly in late summer early autumn, influence reproduction survival elk. Therefore, we estimated seasonal condition 861 female 2,114 capture events from 21 herds Washington, Oregon, Wyoming, Colorado, South Dakota 1998 to 2007. We...
Abstract: Because they do not require sacrificing animals, body condition scores (BCS), thickness of rump fat (MAXFAT), and other similar predictors have advanced estimating nutritional ungulates their use has proliferated in North America the last decade. However, initial testing these was too limited to assess reliability among diverse habitats, ecotypes, subspecies, populations across continent. With data collected from mule deer ( Odocoileus hemionus ), elk Cervus elaphus moose Alces...
Abstract The forage maturation hypothesis (FMH) states that energy intake for ungulates is maximised when biomass at intermediate levels. Nevertheless, metabolic allometry and different digestive systems suggest resource selection should vary across ungulate species. By combining GPS relocations with remotely sensed data on characteristics surface water, we quantified the effect of body size system in determining movements 30 populations hindgut fermenters (equids) ruminants biomes....
Feral horses (Equus ferus caballus) have become abundant on public lands in the American West, particularly over past 10 yr. In areas where they are overabundant, there is risk of habitat degradation. Most previous studies diet and use feral were conducted more than 20 yr ago; rangelands changed considerably that time, so it useful to revisit horse diets. We a study examine using noninvasive methods subjectively compare analysis techniques. collected fecal samples from...
We used 35-year and 4-year ungulate exclosures to determine the effects of elk (Cervus elaphus) herbivory on above-ground below-ground production soil fertility winter range in Rocky Mountain National Park (RMNP), Colorado, USA. paired grazed ungrazed plots evaluate short tall willow (Salix spp.), aspen (Populus upland grass/shrub vegetation associations. measured nitrogen (N) fluxes (litter deposition, fecal urinary deposition from elk, movements N by mineralization, availability,...
Abstract Understanding factors driving resource selection and habitat use of different species is an important component management conservation. Feral horses ( Equus caballus ) are free ranging across various vegetation types in the western United States, yet few studies have quantified their seasonal use. We conducted a study to determine effects community, distance water, topographic variables on 2 feral horse populations Great Basin sagebrush Artemisia spp.) ecosystems west‐central Utah,...
There are two species of free-roaming feral equids in North America: horses ( Equus caballus ) and donkeys or “burros” E . asinus ). Both were introduced as domestic animals to America the early 1500s currently inhabit rangelands across western United States, Canada, all continents except Antarctica. Despite their global distribution, little is known about fine scale spatial ecology. Contemporary research tools assess space use include positioning system (GPS) tracking collars, but older...
The invasive grass cheatgrass (Bromus tectorum L.) presents major challenges for land management and habitat conservation in the western United States. Feral horses (Equus ferus caballus) have become overabundant some areas of West can impact fragile semiarid ecosystems. Amid ongoing efforts to control Great Basin, we conducted a study determine if feral contribute spread through distribution via their feces. We collected horse fecal samples from Little Book Cliffs Herd Management Area...
The special section in this issue of the Journal Wildlife Management presents new science for application to sustainable management free-roaming equids: feral horses (Equus caballus) and burros (E. asinus). engagement all stakeholders, particularly wildlife biology community, is emerging as a critical need based on sound science. Equidae originated North America approximately 10–20 million years ago (Hurlbert 1993, Kelekna 2009) radiated across steppes Eurasia Africa with multiple extinction...
Wild horses (Equus caballus) at Pryor Mountain were studied by direct observation from 1993 through 2007. All present individually identifiable on the basis of coat coloration, head and leg markings, gender, band associations. Of 609 either prior to foaling in or born since, ages precisely known for 491 (observed as a foal). Ages 52 estimated tooth eruption wear patterns, remaining 66 body size, morphology, anecdotal evidence concerning when they range. At varying intensities, never less...
Abstract Fecal DNA collected noninvasively can provide valuable information about genetic and ecological characteristics. This approach has rarely been used for equids, despite the need conservation of endangered species management abundant feral populations. We examined factors affecting efficacy using equid fecal samples genetics. First, we evaluated two collection methods (paper bag vs. ethanol). Then, investigated how time since deposition month impacted microsatellite amplification...
The negative effects of equid grazers in semiarid ecosystems the American West have been considered disproportionate to influence native ungulates these systems because equids' large body size, hoof shape, and short history on landscape relative ungulates. Tools that can analyze degree various ungulate herbivores an ecosystem separate from other variables (climate, anthropomorphic disturbances) be useful managers determining location nonnative herbivore impacts assessing effect management...
Abstract Plant communities in rangeland ecosystems vary widely the degree to which they can compensate for losses herbivores. Ecosystem‐level factors have been proposed affect this compensatory capacity, including timing and intensity of grazing, availability soil moisture nutrients. Arid are particularly challenging predict because their high temporal variability inputs. We used a replicated herbivore exclusion experiment evaluate herbaceous plant responses grazing by large ungulates test...
We compared three fecal steroid metabolite assays for their usefulness in detecting pregnancy among free-ranging Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from Bighorn Canyon National Recreation Area, Wyoming and Montana (USA) captive ewes at ZooMontana Billings, Montana. Fecal samples were collected 11 free-ranging, radio-collared late January–May 2001 20 March to mid-May 2002. Free-ranging monitored the following spring determine whether or not they lambed. In addition, two...
Feral horses are widespread in the western United States, with majority of feral horse herds found Great Basin. There is a federal mandate to manage these order maintain "ecological balance"; however, understanding specific effects grazing on rangeland plant communities this region incomplete. To address research gap, we utilized long-term exclosures and fenceline contrasts evaluate impacts several community variables (diversity, richness, dominance, biomass) species composition. Because can...
Abstract Animals adjust their habitat use patterns in response to changes physiological needs and environmental conditions. Understanding the mechanisms underlying resource selection space across time reveals effects of environment on animals' decisions. We explored availability heterogeneity seasonal annual two free‐roaming feral burro ( Equus asinus ) populations United States within distinct climate conditions: Sonoran Desert Colorado Plateau. As an introduced yet protected species...
ABSTRACT Accurate population estimates provide the foundation for managing feral horses ( Equus caballus ferus ) across western United States. Certain horse populations are protected by Wild and Free‐Roaming Horses Burros Act of 1971 managed Bureau Land Management (BLM) or States Forest Service on designated herd management areas (HMAs) wild territories, respectively. to achieve an appropriate level (AML), which represents number determined BLM contribute a thriving natural ecological...
Conservation of species requires accurate population estimates. We used genetic markers from feces to determine bighorn sheep abundance for a herd that was hypothesized be declining and in need status monitoring. sampled small but accessible portion the population's range where animals naturally congregate at natural mineral lick test whether we could accurately estimate size by sampling an area concentrate. mark-recapture analysis derive estimates, compared estimates this smaller spatial...
ABSTRACT Feral horses ( Equus ferus caballus ) in the western United States are managed by Bureau of Land Management (BLM) and Forest Service designated areas on public lands with a goal maintaining populations balance multiple uses landscape. Small, isolated can be at risk extirpation from stochastic events deleterious genetic effects resulting inbreeding reduced heterozygosity. The diversity feral horse herds is periodically monitored using blood or hair samples collected during management...
Abstract Data from animals equipped with global positioning system collars have advanced our understanding of vertebrates, but this technology has rarely been employed to study feral equids. Hesitation equip equids telemetry in the USA can often be attributed safety concerns stemming one 1980s, where injuries were sustained by horses (Equus ferus caballus) radio-collars. Improvements collar design over ensuing quarter-century may decreased risk collar-related complications; however,...