Publications

The Midcontinent Rift System (MRS) is expressed geophysically by a semi-linear, regional gravity high that trends across the Midcontinent and Great Lakes region of North America. The gravity high is interrupted by two prominent, semi-circular gravity lows, which have been interpreted from modeling and seismic-reflection sections as basement highs of Archean granite (Allen et al., 1997)...

No abstract available.

The American bullfrog (Lithobates catesbeianus) is a non-native invader of aquatic habitats across the northwestern United States. It recently invaded the Yellowstone River, Montana, and has spread to over 140 km of floodplain habitat. We analyzed seven microsatellites in 528 tadpoles sampled across nearly the entire Yellowstone River invasion (about 140 river km) to characterize...

The unprecedented size of the 2017 wildfires that burned nearly 600,000 hectares of central Chile highlight a need to better understand the climatic conditions under which large fires develop. Here we evaluate synoptic atmospheric conditions at the surface and free troposphere associated with anomalously high (active) versus low (inactive) months of area burned in south-central Chile (ca...

Large magnitude snow avalanches pose a hazard to humans and infrastructure worldwide. Analyzing the spatiotemporal behavior of avalanches and the contributory climate factors is important for understanding historical variability in climate-avalanche relationships as well as improving avalanche forecasting. We used established dendrochronological methods to develop a long-term (1867–2019)...

Recent, widespread tree mortality in the western U.S. resulting from changes in climate, pathogens, insect activity, and forest management practices has led to concerns for many ecologically and culturally important species. Within conifers, resin-based defenses have long been recognized as a primary defense mechanism against a variety of insects and pathogens. Oleoresin produced by...

North America's protected lands harbor biodiversity and provide habitats where species threatened by a variety of stressors in other environments can thrive. Yet disease, climate change, and other threats are not limited by land management boundaries and can interact with conditions within protected landscapes to affect sensitive populations. We examined the population dynamics of a...

Wildlife populations in southeast Asia are increasingly experiencing a broad array of anthropogenic threats, and mammalian carnivores are particularly vulnerable. Populations of the Malayan sun bear Helarctos malayanus are estimated to have declined by 30% over the last 30 years from forest conversion to industrial plantations and mortality associated with human–bear conflicts and...

How aquatic insects cope with cold temperatures is poorly understood. This is particularly true for high-elevation species, which often experience a seasonal risk of freezing. In the Rocky Mountains, nemourid stoneflies (Plecoptera: Nemouridae) are a major component of mountain stream biodiversity and are typically found in streams fed by glaciers and snowfields, which are rapidly...

Fish managers must weigh trade-offs among cost, speed, efficiency, and ecological adaptation when deciding how to translocate native salmonids to either establish or genetically augment populations. Remote site incubators (RSIs) appear to be a reasonable strategy, but large-scale evaluations of this method have been limited. We used 129 RSIs to incubate >35,700 eyed embryos of Westslope...

Drought is a complex challenge experienced in specific locations through diverse impacts, including ecological impacts. Different professionals involved in drought preparedness and response approach the problem from different points of view, which means they may or may not recognize ecological impacts. This study examines the extent to which interviewees perceive ecological drought in...

Habitat fragmentation and loss contribute to isolation of wildlife populations and increased extinction risks for various species, including many large carnivores. We studied a small and isolated population of American black bears (Ursus americanus) that is of conservation concern in central Georgia, USA (i.e., central Georgia bear population [CGBP]). Our goal was to evaluate the...