Publications

We collected, examined, and analyzed 368 fish of seven species from 10 sites in the Rio Grande Basin (RGB) during late 1997 and early 1998. Four sites were National Contaminant Biomonitoring Program (NCBP) stations where organochlorine ad elemental contaminants in fish had been monitored from 1969 and through 1986. The other six were USGS-National Stream Quantity Accounting Network (NASQAN) statio

This project collected, examined, and analyzed 217 fish representing three species at 10 stations in the U.S. portion of the Yukon River Basin (YRB) from May to October 2002. Four sampling sites were located on the Yukon River; two were located on the Porcupine River, and one site was on each of the Ray, Tanana, Tolavana, and Innoko Rivers. Norther pike (Esox lucius), longnose sucker (Catostomus c

An understanding of mechanisms of contaminant effects across levels of biological organization is essential in ecotoxicology if we are to generate predictive models for population-level effects. We applied a suite of biochemical, histological, and behavioral end points related to visual structure and function and foraging behavior to evaluate effects of 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) o

The effects of multiple routes of cadmium exposure on juvenile American toads (Bufo americanus) were evaluated using environmentally relevant concentrations. During or after exposure, toads were individually hibernated for 172 days at approximately 4°C. The following experiments were conducted: (1) dermal exposure (hibernation in soil contaminated with up to 120 μg Cd/g  (dry weight)); (2) injecti

No abstract available.

Retinal structure and concentration of retinoids involved in phototransduction changed during early development of rainbow trout Oncorhynchus mykiss, correlating with improvements in visual function. A test chamber was used to evaluate the presence of optokinetic or optomotor responses and to assess the functionality of the integrated cellular, physiological and biochemical components of the visua

Bio- and photo-transformation of two munitions and explosives of concern, 2,6-dinitrotoluene (2,6-DNT) and 2,4,6-trinitrophenol (picric acid) were assessed in spiked marine sediments and water. A sandy and a fine-grained sediment, with 0.25% and 1.1% total organic carbon, respectively, were used for biotransformation assessments at 10 and 20 °C. Sterilized sediments were used as controls for bioti

We sampled fishes monthly from November 2000 to October 2001 at four gravel bar sites along a 34-km stretch of the upper Neosho River in Lyon County, Kansas. We assessed the potential for interspecific competition among stream fishes, with focus on the federally threatened Neosho madtom, Noturus placidus, by using Pearson's correlation analysis with sequential Bonferroni correction of alpha to exa

You've probably heard the adage, "When life gives you lemons, make lemonade!"  Missouri has been given some lemons in the form of bighead and silver carp.  These large, plankton eating fish, native to Asia, were imported into Arkansas in the 1970s to control water quality in fish farms and sewage treatment facilities.  It didn't take long for the fish to escape to the wild, and their populations h

Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 12 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB), and in late 1996 from a reference site in West Virginia. The NCBP sites represented key points (dams, tributaries, etc.) in the largest rivers of the MRB. The NAWQA sites were typically on smaller

Fire-retardant chemicals often are applied in relatively pristine and environmentally sensitive areas that are potentially inhabited by endangered or threatened aquatic species. Avoidance of contaminants is an adaptive behavior that may reduce exposure to harmful conditions. We evaluated the avoidance responses of rainbow trout (Oncorhynchus mykiss) to concentrations of fire-retardant chemicals an

As an integral part of our continuing research in environmental quality assessment approaches, we have developed a variety of passive integrative sampling devices widely applicable for use in defining the presence and potential impacts of a broad array of contaminants. The semipermeable membrane device has gained widespread use for sampling hydrophobic chemicals from water and air, the polar organ