Publications

Chemosensory cues, particularly those emanating from substrate areas occupied by previously hatched young, may play an important role in the reproductive behavior of lake trout Salvelinus namaycush. Support for this hypothesis was obtained in laboratory experiments. Adults were placed in a large circular pool with four experimental reefs. Egg membranes and feces obtained from young that...

We used a mass balance equation relating total mortality of age II and older alewives (Alosa pseudoharengus) to their removals by predatory fish and other sources of mortality as the basis for estimating that the forage base in Lake Michigan could support an additional 13 000 to 21 000 t of lake trout (Salvelinus namaycush) or a total lake trout biomass between 15 000 and 23 000 t. This...

The surface area of submersed macrophytes is often viewed from different perspectives such as substrate for colonization by periphyton, or protective cover for fishes. Consequently, several different methods have been used to measure it. We describe a method for measuring that area with an electronic surface area meter, a device that yields, for large samples of macrophytes, measurements...

The tubificid worm Variechaetadrilus fulleri (Annelida: Oligochaeta) was described by Brinkhurst and Kathman (1983) from the Green River, Kentucky, the only locality from which the species has previously been reported. In 1982-84, a number of specimens of V. fulleri were found in the lower Mississippi River and in an adjacent oxbow lake (Eagle Lake), about 19 river kilometers northwest...

Attempts to establish a 'put-grow-and-take' fishery for rainbow trout (Salmo gairdneri) in Jocassee Reservoir, South Carolina failed despite plantings of 200,000 fish in 1972-1979 because few of the stocked fish survived to legal size. At the same time, a fishery for brown trout (Salmo trutta) was established successfully by planting far fewer fish. Experiments were conducted to...

The threespine stickleback (Gasterosteus aculeatus) was not known to occur in the Great Lakes above Niagara Falls until 1980, when it was collected in South Bay, Manitoulin Island, in the Lake Huron basin. By 1984 this species had been found in tributaries of Lakes Huron and Michigan, and in the open waters of both lakes. All specimens identified were the completely plated morph that is...

As part of continuing studies of the reproductive failure of lake trout (Salvelinus namaycush) in Lake Michigan, we measured the survival of lake trout eggs and fry of different origins and reared in different environments. Eggs and milt were stripped from spawning lake trout collected in the fall of 1980 from southeastern Lake Michigan, northwestern Lake Huron, south central Lake...

I tested the effects of different ration sizes on preferred temperatures of yearling lake charr,Salvelinus namaycush, by feeding them for about 2 weeks on one of four rations and then allowing them to thermoregulate in a temporal thermal gradient for 2 to 3 days. Selected temperatures and ration were directly and linearly correlated: the larger the ration, the higher the temperature...

Contaminant body burdens in lake trout from the Upper Great Lakes have been monitored since 1970 on Lake Michigan and since 1977 and 1978 on Lakes Superior and Huron by USEPA, Great Lakes National Program Office and USFWS, Great Lakes Fishery Laboratory. Analysis of the Lake Michigan data shows that mean PCB concentrations declined from a maximum of 22.91 mg/kg in 1974 to 5.63 in 1982...

Over 10 million cubic meters of sediment are dredged annually from Great Lakes waterways. Because much of this material is taken from harbors, connecting channels, and other nearshore areas that often are contaminated with toxic substances, the sediments proposed for dredging need to be evaluated for the presence of bioavailable contaminants and the potential for toxicity to the biota...

No abstract available.

No abstract available.