Publications

Timber harvest has many effects on aquatic ecosystems, including changes in hydrological, biogeochemical, and ecological processes that can influence mercury (Hg) cycling. Although timber harvest’s influence on aqueous Hg transformation and transport are well studied, the effects on Hg bioaccumulation are not. We evaluated Hg bioaccumulation, biomagnification, and food web structure in...

Methods to quantify solar insolation in riparian landscapes are needed due to the importance of stream temperature to aquatic biota. We have tested three lidar predictors using two approaches developed for other applications of estimating solar insolation from airborne lidar using field data collected in a heavily forested narrow stream in western Oregon, USA. We show that a raster...

1. Greenhouse gas-induced warming in the Arctic has caused declines in sea ice extent and changed its composition, raising concerns by all circumpolar nations for polar bear conservation. 2. Negative impacts have been observed in three well-studied polar bear subpopulations. Most subpopulations, however, receive little or no direct monitoring, hence, resource selection functions (RSF)...

No abstract available.

Inaccurate systematics confound our ability to determine evolutionary processes that have led to the diversification of many taxa. The North American freshwater mussel tribe Lampsilini is one of the better-studied groups in Unionidae, however, many supraspecific relationships between lampsiline genera remain unresolved. Two genera previously hypothesized to be non-monophyletic that have...

Habitat loss can trigger migration network collapse by isolating migratory birds’ breeding grounds from non-breeding grounds. Theoretically, habitat loss can have vastly different impacts depending on the site’s importance within the migratory corridor. However, migration network connectivity and the impacts of site loss are not completely understood. Here we used GPS tracking data from...

Throughout the Intermountain West, there has been significant investment in understanding how social factors influence manager and citizen experiences of drought in particular locations. Yet there is still a gap in knowledge of how human dimensions of drought impacts, planning, and resilience are similar and different across cases and regions. Building on the natural science...

Major geological processes have shaped biogeographical patterns of riverine biota. The Edwards Plateau of central Texas, USA, exhibits unique aquatic communities and endemism, including several species of freshwater mussels. Lampsilis bracteata (Gould, 1855) is endemic to the Edwards Plateau region; however, its phylogenetic relationship with other species in the Gulf coastal rivers and

Maintenance of the natural flow regime is essential for continued wetland integrity; however, the flow regime is greatly influenced by both natural and anthropogenic forces. Wetlands may be particularly susceptible to altered flow regimes as they are directly impacted by water flows at a variety of time scales. In Puerto Rico, contemporary water management is decreasing freshwater...

Ecotones can increase free-living species richness, but little is known about how parasites respond to ecotones. Here we use parasite communities in raccoons (Procyon lotor) to test the hypothesis that parasite communities can be divided into core and satellite species, each with fundamentally different responses to ecotones. We used published parasite surveys to classify parasites as...

Atmospheric nitrogen and sulfur pollution increased over much of the United States during the twentieth century from fossil fuel combustion and industrial agriculture. Despite recent declines, nitrogen and sulfur deposition continue to affect many plant communities in the United States, although which species are at risk remains uncertain. We used species composition data from >14,000...

Historically, closed eastern forests transitioned into open savannas and prairies in the US Midwest, but this transition is poorly understood. To investigate the eastern boundary of the prairie-forest ecotone, we conducted a case study of historic and modern vegetation patterns of the Yellow River watershed in northwest Indiana. Historic vegetation came from the Public Land Survey notes...