Publications

Density-dependent recruitment of the bloater (Coregonus hoyi) in Lake Michigan during and after recovery of the population in about 1977-1983 was best reflected in the fit of the Beverton-Holt recruitment function to age -1 and -2 recruits and estimated eggs of parents surveyed with trawls. A lower growth rate and lower lipid content of bloaters at higher population densities and no...

Water-level regulation has altered the plant species composition and thus the structure of nearshore aquatic macrophyte communities in two regulated lakes in northern Minnesota as compared with a nearby unregulated lake. Results of previous faunal studies in the regulated lakes were used as a basis for assessing the effects of vegetation changes on faunal communities. The unregulated...

Environmental and economic problems associated with the colonization of zebra mussels (Dreissena polymorpha) in western Lake Erie created a need to investigate control mechanisms. Predation by fishes is one potential means of control, but predation on zebra mussels by native fishes in Lake Erie is unknown. The freshwater drum (Aplodinotus grunniens) is the most likely fish predator since...

The 209 polychlorinated biphenyl (PCB) congeners exhibit a wide range in toxicity to fish, birds, and mammals. This paper discusses the use of gas chromatography/mass spectrometry negative chemical ionization (GC/MS-NCI) to quantify congeners of highly suspected toxicity such as IUPAC #77 (3,3',4,4'-tetrachlorobiphenyl) and #126 (3,3',4,4',5-pentachlorobiphenyl). GC/MS analysis time...

Bluegill (Lepomis macrochira) growth varies inconsistently with plant density. In laboratory and field experiments, we explored mechanisms underlying bluegill growth as a function of plant and invertebrate density. In the laboratory, bluegills captured more chironomids (Chironomus riparius) than damselflies (Enallagma spp. and Ischnura spp.), but energy intake per time spent searching...

Emerald shiner (Notropis atherinoides) and spottail shiner (N. hudsonius) were abundant historically in western Lake Erie. Recent changes in the fish community suggest that shiners may not compete favorably with the invading white perch (Morone americana) or the gizzard shad (Dorosoma cepedianum). We examined the diets of emerald and spottail shiner and compared them to other...

Interspecific competition for a food resource (fish eggs) was examined in a laboratory setting between two common benthic organisms of the Great Lakes, the slimy sculpin (Cottus cognatus) and crayfish (Orconectes virilis). In monospecific tests, the median egg predation in aquarium microcosms ranged from 2.5 eggs/d for the sculpin to 3.0 eggs/d for the crayfish. In mixed-species tests...

Harvest restrictions on striped bass Morone saxatilis fisheries in Atlantic coastal states were relaxed in 1990, but consistent, coastwide regulations of the harvest have been difficult to implement because of the mixed‐stock nature of the fisheries and the recognized contamination of Hudson River fish by polychlorinated biphenyls (PCBs). We examined PCB concentrations and stock of...

To better characterize neoplasm epizootics in the Great Lakes basin and their association with families of contaminants, we sampled five locations: the Fox and Menominee rivers, Lake Michigan; Munuscong Lake, St. Mary's River; and the Black and Cuyahoga rivers, Lake Erie. Frequencies of external and liver tumors were determined for brown bullhead (Ictalurus nebulosus) from all locations...

Predation and contaminants are two possible factors in the poor recruitment of young lake charr Salvelinus namaycush in the Great Lakes. We measured the feeding rate of slimy sculpins Cottus cognatus and burbot Lota lota on young lake charr (uncontaminated young from eggs of a hatchery brood stock and contaminated young from eggs of Lake Michigan lake charr) in laboratory test chambers...

In recent years the National Fisheries Research Center-Great Lakes has ranked the potential hazard to fish and invertebrates of various chemical compounds detected in two Great Lakes fishes-- lake trout, Salvelinus namaycush, and walleye, Stizostedion vitreum vitreum (Hesselberg and Seelye 1982). This hazard assessment has included the identification of the potential sources of the...

Abundance and distribution patterns of the caddisflies of the St. Clair-Detroit River system were investigated in 1983–84. Collections of both adults and larvae yielded 70 species representing 34 genera and 12 families. Leptoceridae and Hydroptilidae were the most common families and Ceraclea the most common genus in number of species. This study adds 21 species to the Michigan record...