Publications

Most of the PCB body burden in lake trout (Salvelinus namaycush) of the Great Lakes is from their food. PCB concentrations were determined in lake trout from three different locations in Lake Michigan during 1994–1995, and lake trout diets were analyzed at all three locations. The PCB concentrations were also determined in alewife (Alosa pseudoharengus), rainbow smelt (Osmerus mordax)...

Lake trout Salvelinus namaycush, aged 3 and 6 years and with average weights of 700 and 2,000 g, were grown in laboratory tanks for up to 407 d under a thermal regime similar to that experienced by lake trout in nearshore Lake Michigan. Lake trout were fed alewifeAlosa pseudoharengus and rainbow smelt Osmerus mordax, prey typical of lake trout in Lake Michigan. Of the 120 lake trout used...

In Lake Baikal, three morphotypes of omul Coregonus autumnalis migratorius are recognized; the littoral, pelagic, and deep-water forms. Morphotype assignment is difficult, and similar to that encountered in pelagic and deep-water coregonines in the Laurentian Great Lakes. Principal component analysis revealed separation of all three morphotypes based on caudal peduncle length and depth...

The Northern Refuge in Lake Michigan was established in 1985 as part of a rehabilitation program to stock yearling lake trout Salvelinus namaycush in areas with the best potential for success. Stocking of hatchery-reared lake trout within the refuge began in 1986 at three reefs: Boulder Reef, Gull Island Reef, and Richards Reef. On each reef from 1991 to 1997 we conducted gill-net...

A long history of human-induced degradation of Great Lakes wetlands has made restoration a necessity, but the practice of wetland restoration is relatively new, especially in large lake systems. Therefore, we compiled tested methods and developed additional potential methods based on scientific understanding of Great Lakes wetland ecosytems to providc an overview of approaches for...

Restoration plans for Metzger Marsh, a coastal wetland on the south shore of western Lake Erie, incorporated a fish-control system designed to restrict access to the wetland by large common carp (Cyprinus carpio). Ingress fish passageways in the structure contain slots into which experimental grates of varying size and shape can be placed to selectively allow entry and transfer of other...

Sediment cores collected from the littoral and pelagic zones of Beaver Lake, Michigan record fluctuations in the water level of Lake Superior. Beaver Lake is a small 300 ha lake in Pictured Rocks National Lakeshore (PRNL) now separated from Lake Superior by a dune-capped barrier bar. Cores were collected using a vibracorer from a lake-ice platform in February 1997. A 2.85 m long core in...

Excessive fecal coliform bacteria in public swimming waters can potentially threaten visitor health. Fecal coliform bacteria (1984-1989) and Escherichia coli (1990-1995) density were monitored weekly at the Indiana Dunes National Lakeshore beaches for 12 summers, and park officials closed swimming areas when fecal coliform density exceeded the state water quality criteria (400 CFU fecal...

From 1993 to 1997, 60 species of Anisoptera (dragonflies) and Zygoptera (damselflies) were found in Lake and Porter Counties, Indiana, including Indiana Dunes National Lakeshore, in contrast to 34 species that were recorded historically from this region. We added 17 new species to Lake County's odonate records and 39 new species to the 5 previously recorded in Porter County. Several...

The bottom fauna of western Lake Erie has changed dramatically over the past 50 years in response to environmental degradation and biological invasions. In 1953, low dissolved oxygen reduced the biodiversity of that fauna, especially burrowing mayflies and freshwater mussels (Unionidae). Canada and the United States signed the Great Lakes Water Quality Agreement in 1972. By 1982, over 7...

This paper describes the life history, distribution, and abundance of Hexagenia in Lake Erie, as shown by sediment core samples containing preserved Hexagenia remains dating back to about 1740, periodic sampling of living nymphal populations since about 1930, observations of emergences and mating swarms of adults, and the incidence of Hexagenia in fish stomachs. The roles of...

This paper presents brief fragments of the results of joint Russia-US research conducted through the cooperative project entitled, 'Comparative ecology of exotic invaders and ecologically equivalent species of hydrobionths in the Great Lakes of the world: Lake Baikal and the Laurentian Great Lakes.' The project was executed under the Agreement on Scientific Cooperation between the...