Rural development in Western Wyoming provides an example of habitat fragmentation that alters mule deer use of migration route habitat.

We are evaluating the influence of development type and intensity on migratory behavior of several western Wyoming mule deer (Odocoileus hemionus) populations using GPS collar data. These migration routes span a gradient of development, from intact habitat to housing infrastructure to landscapes developed for petroleum extraction.

We are evaluating how the bark beetle epidemic occurring in Wyoming’s forests may influence elk and hunter movements and interactions. Landscape-level changes to the forest as a result of the bark beetle may result in changes in where elk forage, in turn, potentially changing the ability of hunter to access and harvest elk. Understanding how the bark beetle epidemic is affecting elk and hunters will help wildlife and land managers manage Wyoming’s changing forests.

The objectives of the Sublette Moose Project are 3-fold: First, we are providing a baseline synthesis of Sublette moose seasonal-habitat use, nutrition and demography for that herd, which is the largest in Wyoming. Second, we are assessing the relative influence of predator density (wolves and grizzly bears), habitat condition and weather on the demography of the Jackson and Sublette moose herds. Third, we are testing the influence of wolf presence on movement rates and habitat use of moose in the Jackson region.

Wildlife managers have struggled for decades to maintain populations at or near local carrying capacities because they often lack the tools necessary for identifying when and where resources, such as food, are limiting. Accordingly, the goal of this study is to identify the habitat, climatic, behavioral and nutritional characteristics that reflect a population experiencing resource limitation. By using a variety of field and lab methods to identify resource limitations, we will develop a tool-set that managers can use to measure resource limitation and make science-based management decisions.

Traditional herd composition surveys are completed using helicopters or fixed wing aircraft, proving to be both costly and dangerous. Remote photography could provide an alternative method for collecting composition data that is more cost efficient and safer. Trail cameras are providing data pertaining to both herd composition and herd migration timing; information useful to regional biologists who manage these populations through sustainable harvest practices. We are investigating the efficacy of this new methodology and it’s potential for long term monitoring of migratory elk herds in the Greater Yellowstone Ecosystem.

Completed Projects

Our study population, the Clarks Fork elk herd, is a partially-migratory population of about 4,500 individuals near Cody, Wyoming. Collars were distributed evenly throughout its migratory and nonmigratory subpopulations.

We are working to understand the changing demography and distribution of the Clarks Fork elk herd, which ranges widely in the Absaroka Mountains between Cody, WY and the headwaters of the Lamar River inside Yellowstone National Park (YNP).

This project has been conducted in collaboration with the U.S. Fish and Wildlife Service, the Wyoming Game and Fish Department, and many private ranches. An important part of our field work was to capture wolves so that we could monitor their movements in relation to native and domestic ungulates.

The Absaroka Wolf-Cattle project was created to evaluate wolf habitat selection and predation in a multiple-use landscape in the Absaroka Mountains of Wyoming, an area characterized by high levels of wolf-cattle conflict and a changing distribution of migratory and nonmigratory elk.

Energy development is economically important for Wyoming and the nation. Unfortunately, much development occurs in previously intact habitats that are important for wildlife, including many species listed as Species of Greatest Conservation Need by the Wyoming Game and Fish Department. (Photo: Stewart Point Rig, 2003, L. Baker. Courtesy of Wyoming Outdoor Council.)

With over 200 Species of Greatest Conservation Need (SGCN) identified by Wyoming’s State Wildlife Action Plan, and energy infrastructure likely to double in the next twenty years, there are insufficient time and resources to conduct species-specific, detailed studies.

Devils Canyon

Over the past 120 years, many bighorn sheep (Ovis canadensis) herds throughout Wyoming and the Rocky Mountain west have declined or been extirpated due to disease, habitat loss and fragmentation, and competition with domestic sheep. Since 1934, Wyoming has conducted a number of bighorn sheep reintroduction efforts into historically occupied ranges, which are commonly xeric, canyon habitats. Most Wyoming transplants utilize bighorn sheep from a source herd on Whiskey Mountain, near Dubois, Wyoming. Bighorn sheep from this herd are migratory and adapted to summering in high-elevation alpine habitat.

Elk Nutritional Condition

For many animal taxa, nutritional condition (i.e., fat levels) is a balance of food intake that increases condition versus energy outputs (i.e., cost of reproduction) that diminish condition. While nutritional condition gradients are common in nature, relatively little is known about how nutritional condition influences behavior. Current management practices in Wyoming offer a rare opportunity to evaluate the influence of nutritional condition on the behavioral strategies of a large, free-ranging population of elk (Cervus elaphus). The Wyoming Game and Fish Department (WGFD) operates 22 winter feedgrounds for population and disease management.

During winter, available browse includes the stems of willows, aspen, bog birch, and subalpine fir, among others. Moose spend a lot of their time along the edges of willow and conifer patches for food and cover.

We are working to understand the influnece of seasonal limitations and limiting factors on ungulate populations. Landscapes are being altered at increasing rates from both anthropogenic and natural causes.

female elk and female cow at watering hole in Arizona

Brucellosis is a bacterial disease resulting in abortions for some ungulates. It remains endemic to elk and bison in the Greater Yellowstone Ecosystem and can be transmitted to cattle via comingling between March and May when most abortions occur. We are using GPS collar data from adult female elk captured on winter feedgrounds in Wyoming to a) develop a movement model for elk, b) simulate elk distribution under varying annual weather patterns, and c) map areas of high risk for interspecific brucellosis transmission.

Mule deer in western Wyoming migrate 18-140 km to high-elevation summer ranges where they access high quality forage and accumulate fat reserves that help them survive the harsh winters. The ability to identify and prioritize these migration routes may improve management and land-use planning.

Increased levels of energy development across the Intermountain West have created a variety of wildlife management and conservation concerns. Because many of the energy resources in the region occur in shrub-dominated basins, management concerns have focused on native shrub communities and associated species, including mule deer. Two of the more pressing concerns are how mule deer respond when critical habitats (e.g., winter range) are impacted by development and how their migration routes can be identified and prioritized for conservation.

Burbot are a species of conservation concern in Wyoming. We are using otolith microchemistry to differentiate populations, reconstruct movement patterns, and determine natal origins

Reconstructing the life histories of fish has been a challenging problem for fisheries biologists. Unlike terrestrial organisms, the aquatic environments fish inhabit make direct observations difficult. Traditionally, fisheries biologists have tracked fish using unique fin clips, tagging, telemetry, and use of food dyes that mark bony parts of fish that can be viewed using UV lighting.

Populations of Shiras moose (Alces alces shirasi) in Wyoming and most western states have experienced declines in population size, and recruitment of young in recent decades. Wildlife managers have expressed increasing concern for moose populations and harvest quotas have been reduced accordingly throughout much of their range.

Field crews tracked GPS-collared bighorn sheep using radio-telemetry during summers 2008, 2009, and 2010.

Loss of migration and access to traditional seasonal ranges are threats facing many ungulate populations in Wyoming and worldwide. This study evaluates the seasonal habitat selection strategies of a formerly migratory bighorn sheep population and the impact of winter backcountry recreation on habitat use.

(photo credit: Arthur Middleton)

The Wyoming Game and Fish Department’s survey, data collection, and modeling protocols have evolved over the years but may not be optimized to allow efficient management of mule deer and other ungulates under current fiscal, logistical, or environmental constraints. There is a need to ensure monitoring and modeling practices generate the most accurate and cost-effective population estimates possible.

Bar-tailed Trogon.

Island biogeography theory resulted in now-classic predictions about how habitat fragmentation influences species richness. In particular, small and isolated remnants should have fewer species than larger and less isolated remnants as a result of higher extinction rates and lower colonization rates.