Publications

Aim Based on a priori hypotheses, we developed predictions about how avian communities might differ at the edges vs. interiors of ecoregions. Specifically, we predicted lower species richness and greater local turnover and extinction probabilities for regional edges. We tested these predictions using North American Breeding Bird Survey (BBS) data across nine ecoregions over a 20-year...

Mid Atlantic coastal salt marshes contain a matrix of vegetation diversified by tidal pools, pannes, and creeks, providing habitats of varying importance to many species of breeding, migrating, and wintering waterbirds. We hypothesized that changes in marsh elevation were not sufficient to keep pace with those of sea level in both vegetated and unvegetated Spartina alterniflora sites at...

The first commercial pesticide derived from a class of compounds known as halogenated pyrroles was registered for use in the United States in 2001. Chlorfenapyr degrades slowly in soil, sediment, and water and is highly toxic to birds. Information on biochemical or histological endpoints in birds is lacking; therefore, a two‐year study was conducted to provide information needed to...

Disseminated visceral coccidiosis (DVC) was unexpectedly recognized in a wild white-naped crane (Grits vipio) killed by phosphamidon insecticide. On gross pathologic examination, widely disseminated white nodules were found on the serosa of the proventriculus, gizzard, and intestine, as well as on the surface and in the parenchyma of liver, spleen, and cardiac muscle. Microscopically...

The Pike Hill Copper Mine Superfund Site in the Vermont copper belt consists of the abandoned Smith, Eureka, and Union mines, all of which exploited Besshi-type massive sulfide deposits. The site was listed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004 due to aquatic ecosystem impacts. This study was intended to be a precursor to a formal remedial

Knowledge of animal abundance is fundamental to many ecological studies. Frequently, researchers cannot determine true abundance, and so must estimate it using a method such as mark-recapture or distance sampling. Recent advances in abundance estimation allow one to model heterogeneity with individual covariates or mixture distributions and to derive multimodel abundance estimators that

Lead poisoning of waterfowl has been reported for decades in the Coeur d'Alene River Basin (CDARB) in Idaho as a result of the ingestion of lead-contaminated sediments. This study was conducted to determine whether the addition of phosphoric acid to CDARB sediments would reduce the bioavailability and toxicity of lead to the liver and kidney of mallards (Anas platyrhynchos). Mallards...

Coastal waterbirds are vulnerable to water-level changes especially under predictions of accelerating sea-level rise and increased storm frequency in the next century. Tidal and wind-driven fluctuations in water levels affecting marshes, their invertebrate communities, and their dependent waterbirds are manifested in daily, monthly, seasonal, annual, and supra-annual (e.g., decadal or 18...

Methyl mercury (MeHg) readily passes through biological membranes, accumulates in individuals, and biomagnifies in higher order predators. It is acutely toxic to some birds at 5-15 parts per million (ppm) wet weight in the diet, and it can damage the central nervous system, impair reproduction, and retard growth and development. The effects of MeHg on reproduction in wild raptors are...

Part of the mission of the National Park Service is to preserve the natural resources, processes, systems, and associated values of its units in an unimpaired condition. Environmental contamination and pollution processes are well recognized stressors addressed by its management policies and plans. A recent study indicates that contemporary terrestrial vertebrate ecotoxicological data...

The Culpeper basin is part of a much larger system of ancient depressions or troughs, that lie inboard of the Atlantic Coastal Plain, and largely within the Applachian Piedmont Geologic Province of eastern North America, and the transition region with the neighboring Blue Ridge Geologic Province. This basin system formed during an abortive attempt to make a great ocean basin during the...

The Louisiana coastal zone, comprising the Mississippi River delta plain stretching nearly 400 km from Sabine Pass at the Texas border east to the Chandeleur Islands at the Mississippi border, represents one of North America’s most important coastal ecosystems in terms of natural resources, human infrastructure, and cultural heritage. At the same time, this region has the highest rates...