Publications

In the environment, lipophilic contaminants such as halogenated aromatic hydrocarbons (HAHs, e.g., polychlorinated biphenyls, PCBs) and polycyclic aromatic hydrocarbons (PAHs, e.g., benzo[a]pyrene) readily bioaccumulate in fish, and the bioaccumulation of these lipophilic chemicals by adult fish may have significant consequences on the development and survival of their offspring...

Non-mutagenic components interfered with the ability of the standard Ames/salmonella assay to detect mutagenicity in extracts of contaminated Great Lakes sediments. The use of gel permeation chromatography (GPC) to remove these macromolecules from methylene chloride extracts prior to Ames testing enhanced the likelihood of transfer of mutagenic components into dimethyl sulf oxide (the...

Lipid depletion is currently believed to be the primary factor limiting flight duration of migrating birds in North America, while the influence of water loss is thought to be small. Three migrating species of passerines, wood thrush (Hylocichla mustelina), Swainson's thrush (Catharus ustulatus), and summer tanager (Piranga rubra) were captured during the 1993 spring migration just after...

Expansion of the breeding distribution of the Fulvous whistling-duck (Dendrocygna bicolor) into the southeastern United States after the mid-1800s coincided with the establishment of rice (Oryza sativa) cultures in Texas, Louisiana, and Florida. In southern Louisiana, where approximately 80% of rice is aerially seeded in water, Fulvous whistling-ducks are suspected of feeding extensively...

No abstract available.

The Laguna Madre of Texas supports the most extensive seagrass meadows in the western Gulf of Mexico, In 1988 seagrasses covered 730 km2 or about three-quarters of the embayment. Halodule wrightii dominated the entire upper laguna, and total biomass was quite uniform near 160 g˙m-2 throughout. Four species shared dominance in the lower laguna. Where present mean biomass of Thalassia...

Toxicity tests conducted under field conditions present an interesting challenge for statistical modelling. In contrast to laboratory tests, the concentrations of potential toxicants are not held constant over the test. In addition, the number and identity of toxicants that belong in a model as explanatory factors are not known and must be determined through a model selection process. We...

The effect of alternate rainfall scenarios on acidification of a forested watershed subjected to chronic acidic deposition was assessed using the model of acidification of groundwater in catchments (MAGIC). The model was calibrated at the Panola Mountain Research Watershed, near Atlanta, Georgia, U.S.A. using measured soil properties, wet and dry deposition, and modeled hydrologic...

Abstract not supplied at this time

The herbicide acetochlor [2-chloro-N-(ethoxymethyl)-N-(2-ethyl-6-methylphenyl)acetamide] was given conditional registration in the United States by the U.S. Environmental Protection Agency in March 1994. This registration provided a rare opportunity to investigate the occurrence of a pesticide during its first season of extensive use in the midwestern United States. Water samples...

Although denitrification has the potential to reduce nitrate (NO3a??) pollution of surface waters, the quantification of denitrification rates is complex because it requires differentiation from other mechanisms and is highly variable in both space and time. This study first measured potential denitrification rates at a wetland forest site in south Louisiana before receipt of secondary...

Deformities have been reported in many species of colonial waterbirds from several localities on the Laurentian Great Lakes. The hypothesis that deformities were caused by either polychlorinated biphenyls (PCBs) or contaminants measured as 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TCDD-EQs) is tested in this review of available data on concentrations of contaminants in eggs and...