Publications

We developed a method to estimate mortality rates of adult fish caused by entrainment through the propellers of commercial towboats operating in river channels. The method combines trawling while following towboats (to recover a fraction of the kills) and application of a hydrodynamic model of diffusion (to estimate the fraction of the total kills collected in the trawls). The sampling problem is

High rates of Common Loon (Gavia immer) chick mortality have been documented in Wisconsin, especially on acidic lakes, but causes and timing of chick mortality are poorly understood. We modified and evaluated a subcutaneous transmitter implant technique for Common Loon chicks using wild and captive reared chicks. Results indicated that behavior, growth, energy expenditure, and survival did not dif

We used radio telemetry to evaluate the movement and habitat use of paddlefish Polyodon spathula in the upper Mississippi River and two tributary rivers. Radio transmitters were surgically implanted into 71 paddlefish in Navigation Pools 5A and 8 of the upper Mississippi River, the Chippewa River, and the Wisconsin River during fall 1994 through fall 1996. Radiotagged paddlefish were located throu

The aim of this study was to evaluate the recovery and survival of four species of unionid mussles [pimpleback, Quadrula pustulosa pustulosa (I. Lea, 1831); spike, Elliptio dilatata (Rafinesque, 1820); Higgins eye, Lampsilis higginsii (I. Lea, 1857); and pocketbook, Lampsilis cardium (Rafinesque, 1820)] that were experimentally relocated to in situ refugia in the St Croix River of Minnesota and Wi

We conducted a dose–response laboratory study to quantify the level of mercury exposure associated with negative effects on the development of common loon chicks reared in captivity from hatch to 105 days. A dose regimen was implemented that provided exposure levels that bracketed relevant exposure levels of methyl mercury found in loon chicks across North America. We observed no overt signs of me

Previous research reported that concentrations of selenium in the livers of 88a??95% of lesser scaup from locations in Lake Erie, Lake St. Clair, and Lake Michigan, USA were either elevated (10a??33 A?g/g dry weight [dw]) or in the potentially harmful range (>33 A?g/g dw). In order to determine the geographic extent of these high selenium concentrations, we collected lesser scaup in Louisiana, Ark

Use of 3-trifluoromethyl-4-nitrophenol (TFM) is limited geographically to the Great Lakes basin where it is the principal agent used in control of the sea lamprey (Petromyzon marinus). It is clear from available data that TFM has effects on the environment, but the effects reported are transient. Individual organisms and aquatic communities return to pretreatment conditions after lampricide treatm

No abstract available.

Blackbirds frequently use ripening sunflower (Heltantbus annuus) as a food source in the northern Great Plains. In 1999 and 2000, the avicide DRC-1339 (3-chloro-4-methylaniline hydrochloride) was used experimentally on fall-ripening sunflower fields in North Dakota so researchers could evaluate its effectiveness for reducing crop depredations by blackbirds. DRC-1339 was applied to rice and broadca

Two methods were compared for delineating land use near shallow monitoring wells. These wells were used to assess the effects of agricultural cropland on the quality of recently recharged ground water in two sand and gravel aquifers located near land surface. The two methods for delineating land use near wells were (1) the sector method, which used potentiometric-surface maps to estimate average f

Concentrations of chloramine-T must be monitored during experimental treatments of fish when studying the effectiveness of the drug for controlling bacterial gill disease. A surrogate analytical method for analysis of chloramine-T to replace the existing high-performance liquid chromatography (HPLC) method is described. A surrogate method was needed because the existing HPLC method is expensive, r

Water-quality data collected from 1993-99 at five sites on Bluff, Deer, and Chisholm Creeks and from 1988-99 at five sites in the North Canadian River indicated that there were significant differences in constituent values among sites for water properties, major ions, trace elements, nutrients, turbidity, pesticides, and bacteria. Concentrations of dissolved solids and sulfate generally decreased