Publications

The U.S. Endangered Species Act (ESA) allows listing of subspecies and other groupings below the rank of species. This provides the U.S. Fish and Wildlife Service and the National Marine Fisheries Service with a means to target the most critical unit in need of conservation. Although roughly one-quarter of listed taxa are subspecies, these management agencies are hindered by uncertainties about ta

Bovine tuberculosis (BTB) is an exotic disease invading the buffalo population (Syncerus caffer) of the Kruger National Park (KNP), South Africa. We used a sex and age-structured epidemiological model to assess the effectiveness of a vaccination program and define important research directions. The model allows for dispersal between a focal herd and background population and was parameterized with

Effective design of avalanche hazard mitigation measures requires long-term records of natural avalanche frequency and extent. Such records are also vital for determining whether natural avalanche frequency and extent vary over time due to climatic or biophysical changes. Where historic records are lacking, an accepted substitute is a chronology developed from tree-ring responses to avalanche-indu

Tailed frogs (Ascaphus spp.) oviposit in cryptic locations in streams of the Pacific Northwest and Rocky Mountains. This aspect of their life history has restricted our understanding of their reproductive ecology. The recent split of A. montanus in the Rocky Mountains from A. truei was based on molecular differentiation, and comparisons of their ecology are limited. Our objectives were to provide

No abstract available.

What have we learned so far about how climate change is affecting our global environment? Studies show that it adversely affects human and natural systems by   • reducing biodiversity • altering hydrological systems • impairing biological and chemical cycles • making it more difficult to restore degraded ecosystems Climate is not the only factor in the deterioration of natural systems.We are makin

In a museum of avalanche phenomena, glide cracks and glide avalanches might be housed in the “strange but true” section. These oddities are uncommon in most snow climates and tend to be isolated to specific terrain features such as bedrock slabs. Many glide cracks never result in avalanches, and when they do, the wide range of time between crack formation and slab failure makes them highly unpredi

No abstract available.

Instrumental climate records suggest that summer precipitation and winter snowpack in Glacier National Park (Glacier NP), Montana, vary significantly over decadal to multidecadal time scales. Because instrumental records for the region are limited to the twentieth century, knowledge of the range of variability associated with these moisture anomalies and their impacts on ecosystems and physical pr

No abstract available.

Dams disrupt the flow of both of water and sediment through a watershed. Channel morphology is a function of discharge and sediment load, and perturbations caused by dams often alter channel form, causing significant geomorphic and, potentially, ecological changes (e.g. Petts and Gurnell, 2005). At the first order, dams often produce a flow regime that is profoundly altered in the timing, magnitud

Despite the widespread use of redd counts to monitor trends in salmonid populations, few studies have evaluated the uncertainties in observed counts. We assessed the variability in redd counts for migratory bull trout Salvelinus confluentus among experienced observers in Lion and Goat creeks, which are tributaries to the Swan River, Montana. We documented substantially lower observer variability i