Publications

Uptake of sediment-associated contaminants by the oligochaete Lumbriculus variegatus was evaluated after 1, 3, 7, 14, 28, and 56 d of exposure to a field-collected sediment contaminated with DDT and its metabolites, dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE), or to a field-collected sediment contaminated with polycyclic aromatic hydrocarbons (PAHs). Depuration

The Topeka shiner (Notropis topeka) is a small native cyprinid species that has declined throughout its range in the Central Great Plains Region of the United States. Declines of the species have been associated with numerous factors including water quality, physical habitat alteration and predation. The N. topeka occurs in the Moniteau Creek Watershed of Cooper and Moniteau Counties of Central Mi

Amphibians developing in wetlands embedded within or near agricultural lands may frequently encounter chemical mixtures. The objectives of our study were to determine the effects that post-application concentrations of an insecticide (carbaryl) and an herbicide (atrazine) have on body mass, development, and survival of two anuran species (southern leopard frog, Rana sphenocephala; American toad, B

The effects of bighead carp Hypophthalmichthys nobilis on native planktivores in the USA is unknown. The objectives of this study were to experimentally test for competitive interactions between age-0 bighead carp and age-0 paddlefish Polyodon spathula. Differences among water chemistry variables, invertebrate densities, and relative growth of fish were assessed in mesocosms. Water chemistry varia

Environmental contamination has been suspected of being partially responsible for recent declines in amphibian populations. It is often not feasible to identify all of the compounds in an environment, nor the concentrations in which they are present. SPMDs are passive sampling devices that uptake lipophilic compounds from the environment in a manner similar to aquatic organisms. The extracts from

The National Contaminant Biomonitoring Program (NCBP) was initiated in 1967 as a component of the National Pesticide Monitoring program. It consists of periodic collection of freshwater fish and other samples and the analysis of the concentrations of persistent environmental contaminants in these samples. For the analysis, the common approach has been to apply the mixed two-way ANOVA model to comb

Despite being banned in many countries, dichlorodiphenyltrichloroethane (DDT) and its metabolites dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) continue to be found in fish tissues at concentrations of concern. Like o,p -DDT, o,p -DDE is estrogenic and is believed to exert its effects through binding to the estrogen receptor. The limited toxicologic data for o,p -

We evaluated the roles of geomorphic and hydrologic dynamics in determining physical stream habitat in Bear Creek, a stream with a 239 km2 drainage basin in the Ozark Plateaus (Ozarks) in northern Arkansas. During a relatively wet 12-month monitoring period, the geomorphology of Bear Creek was altered by a series of floods, including at least four floods with peak discharges exceeding a 1-year re

Voyageurs National Park (VOYA), which was established in 1975, contains significant aquatic resources with about 50% of its total area of 883 km2 (341 mi2) consisting of aquatic habitats.  In addition to the Park's 30 named lakes, there are numerous wetlands including hundreds of beaver ponds.  Due to the Park's size and location in the drainage basin, aquatic resources within the Park are particu

No abstract available.

A major challenge to contaminant monitoring programs is the selection of an appropriate suite of measurements for assessing exposure and effects. Early monitoring programs relied solely on residue analysis to detect the organochlorine compounds that were in use at that time. A shift to the use of more transient, less persistent chemicals required that a new set of tools be developed to determine i

Original research discusses the protocols and approaches to studying the effects of multiple environmental stressors on amphibian populations and gives new perspectives on this complicated subject. This new publication integrates a variety of stressors that can act in concert and may ultimately cause a decline in amphibian populations.Sixteen peer-reviewed papers cover:Toxicity Assessment examines