Publications

Stock-recruit models typically use only spawning stock size as a predictor of recruitment to a fishery. In this paper, however, we used spawning stock size as well as larval density and key environmental variables to predict recruitment of white crappies Pomoxis annularis and black crappies P. nigromaculatus, a genus notorious for variable recruitment. We sampled adults and recruits from...

We evaluated the Wisconsin bioenergetics model for lake whitefish Coregonus clupeaformis in the laboratory and in the field. For the laboratory evaluation, lake whitefish were fed rainbow smelt Osmerus mordax in four laboratory tanks during a 133-d experiment. Based on a comparison of bioenergetics model predictions of lake whitefish food consumption and growth with observed consumption...

We examined diets of fishes from gillnet and egg pump collections conducted on reefs in western Lake Erie during walleye (Sander vitreus) egg incubation periods from 1994–1999 and 2004 to assess incidence of walleye eggs in fish diets. We collected no potential egg predators in samples taken in 1994 but from 1995–1999 and in 2004 we caught 22 different species of fish on reefs in...

This study evaluates the accuracy of optically stimulated luminescence to date well-preserved strandline sequences at Manistique/Thompson bay (Lake Michigan), and Tahquamenon and Grand Traverse Bays (Lake Superior) that span the past ∼4500 yr. The single aliquot regeneration (SAR) method is applied to produce absolute ages for littoral and eolian sediments. SAR ages are compared against...

Because of growing concern in the Great Lakes over declines in abundance and growth of lake whitefish (Coregonus clupeaformis) and declines in abundance of the benthic amphipod Diporeia spp., a workshop was held to examine past and current trends, to explore trophic links, and to discuss the latest research results and needs. The workshop was divided into sessions on the status of...

The lake whitefish (Coregonus clupeaformis) was an important member of the native fish community and a valued commercial species in Lake Ontario. Lake whitefish were common in U.S. waters of the lake until 1965 and very abundant in Canadian waters through the early 1970s, although their numbers declined shortly thereafter. During 1975-1985, lake whitefish stocks remained depressed...

Burrowing-mayfly nymphs such as Hexagenia spp. have been used extensively in North America and Europe as a biomonitoring tool to indicate mesotrophic water quality, yet infestation by associated parasites has not been well documented. We performed laboratory analysis of archived samples of Hexagenia spp. nymphs collected in 1985 and 1986 to provide base-line data on the distribution...

Two hypotheses have been proposed to explain the dynamics of sympatric populations of deepwater sculpin (Myoxocephalus thompsonii) and slimy sculpin (Cottus cognatus). The first hypothesis is that slimy sculpins negatively affect survival of deepwater sculpins, and therefore deepwater sculpins coexist with slimy sculpins only when a keystone predator, lake trout (Salvelinus namaycush)...

The U.S. Environmental Protection Agency and Environment Canada are supporting the development of indicators of ecosystem health that can be used to report on progress in restoring and maintaining the Great Lakes ecosystem, as called for in the Great Lakes Water Quality Agreement between the United States and Canada. One indicator under development is based on burrowing mayflies...

The suppression of sea lamprey populations, Petromyzon marinus (Linnaeus), was modeled using four different applications of the male sex pheromone: (1) pheromone-baited traps that remove females from the spawning population, (2) pheromone-baited decoys that exhaust females before they are able to spawn, (3) pheromone-enhanced sterile males that increase the proportion of non-fertile...

The parasitic sea lamprey (Petromyzon marinus) has been a serious pest since its introduction into the Great Lakes, where it contributed to severe imbalances in the fish communities by selectively removing large predators (Smith 1968; Christie 1974; Schneider et al.1996). Since the 1950s, restoration and maintenance of predator-prey balance has depended on the Great Lakes Fishery...

Developmental progression of lake trout (Salvelinus namaycush) embryos was examined with light and scanning electron microscopy. From this examination, key developmental stages were described in detail. The key developmental stages were then applied to individual lake trout egg lots incubated in constant temperatures of 2, 4, 6, 8, and 10°C. We used Belehradek's, Thermodynamic, and Power...