Publications

Translocations have been widely used to restore and conserve bighorn sheep (Ovis canadensis) populations in North America. Some translocations have been successful, but many populations remain small and genetically isolated. Population structure can influence the viability and long-term success of reintroductions. Social ungulates often function as interconnected subpopulations...

No abstract available.

Mule deer (Odocoileus hemionus) are declining in abundance across their broad distribution in western North America. Identifying drivers of mule deer demography could inform habitat restoration. However, linking habitat quality to vital rates is challenging and often done indirectly using proxy metrics. We combine habitat selection with climate-related effects to identify synergistic...

Understanding social aggregation patterns in ungulate herds is essential for gaining behavioral insights, optimizing resource use, reducing human-wildlife conflict, and managing disease risk. As chronic wasting disease is the preeminent disease-related threat to cervid populations in North America, knowledge of contact between individuals and spatiotemporal patterns of aggregation...

The Arizona Toad (Anaxyrus microscaphus) has been petitioned for protection under the U.S. Endangered Species Act (ESA) and is under evaluation for inclusion as a Covered Species under the Clark County Multi Species Habitat Conservation Plan Amendment (Clark County Department of Comprehensive Planning and USFWS, 2001; USFWS, 2015b). Although the species is locally abundant in some parts...

Freshwater species are increasingly threatened by climate change, yet our ability to assess their vulnerability remains incomplete. Typically, climate change vulnerability assessments (CCVAs) evaluate three components: exposure, sensitivity, and adaptive capacity. Adaptive capacity, defined as the ability of a species to adjust to changing conditions, provides critical insight into how...

Large magnitude snow avalanches (destructive size ≥ D3) impact settlements, transportation corridors, and public safety worldwide. In Colorado, United States, avalanches have killed more people than any other natural hazard since 1950. In March 2019, a large magnitude avalanche cycle occurred throughout the entire mountainous portion of Colorado resulting in more than 1000 reported...

This chapter summarizes the location, status, and projections of glaciers in Alaska and western North America. Recent events, including the 2021 surge of Muldrow Glacier in Denali National Park and Preserve, Alaska, are summarized. The implications of glacier loss for ecosystems, water resources, and mountain hazards are discussed.

Warming freshwaters can have profound effects on species composition and community structure and can increase the consumptive demand of predators. Here we explore synergistic impacts of warming and invasion within a freshwater community in Southcentral Alaska (USA). We quantified changes in population structure and predator diet composition using observed data for an introduced...

In the past 25 years new information has been obtained on the migrations and movements of mountain sheep (bighorn [Ovis canadensis], thinhorn [Ovis dalli]). This chapter provides a comprehensive overview of mountain sheep migration and other movements across their broad distribution in western North America. Across the range of mountain sheep, migrations and other seasonal movements...

Wildlife and their habitats face profound challenges from climate and landscape-scale changes that extend beyond the influence and time horizon of most biologists and land managers. In this changing environment, long-term datasets can enhance assessments of how demographic trends respond to interactions among local (e.g., habitat restoration decisions) and broad extent drivers, including...

The U.S. Geological Survey (USGS) and Southern California Coastal Water Research Project supported Channel Islands National Park, The Nature Conservancy’s (TNC) Santa Cruz Island Preserve, and University of California San Diego (UCSD) researchers in using environmental DNA sampling to monitor for invasive Argentine ant (Linepithema humile) and to describe spatial biodiversity patterns in...