Publications

We found Compsopogon cf. coeruleus for the first time in the Laurentian Great Lakes, growing on limestone rocks at a depth of 21 m on Six Fathom Bank in central Lake Huron. It is the first freshwater red alga to be found in the Great Lakes and the only red alga ever found on an offshore reef in the Great Lakes. However, because this alga usually inhabits water 10–28 °C and has not...

The importance of zooplankton in the diet of yellow perch (Perca flavescens), white perch (Morone americana), walleyes (Stizostedion vitreum vitreum), and white bass (M. chry-sops)was assessed in the central basin of Lake Erie in 1985–1988. Zooplankton were collected by vertical hauls in 1987–1988 and fish with a rock-hopper trawl. Although copepods (calanoid and cyciopoid) were the...

We sampled phytoplankton, zooplankton, and alewives Alosa pseudoharengus and measured water temperature in Lake Ontario during 1981–1986. Through the use of general linear regression models we then sought evidence of control of the eplimnetic zooplankton community (mid-July to mid-October) by producers, consumers, and temperature. Our measures of the zooplankton community were total...

As part of the study of the Upper Great Lakes Connecting Channels sponsored by the U.S. Environmental Protection Agency, the U.S. Fish and Wildlife Service examined the occurrence ofHexagenia nymphs and visible oil in sediments at 250 stations throughout the St. Marys River and the St. Clair-Detroit River system from May 14 to June 11, 1985. The mean density of Hexagenianymphs per square...

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...

We examined the diet of juvenile lake trout Salvelinus namaycush (

These data, collected during 1942-1944 by Dr. David C. Chandler, describe the density, biomass, and growth of a now extinct population of burrowing mayfly nymphs (primarily Hexagenia limbata) that lived in the sediments of western Lake Erie near South Bass Island. The growth dynamics of this population have not previously been documented. Female nymphs grew faster than males and were...

Dreissena polymorpha (Pallas), a small mussel common throughout most of Europe, was discovered in June of 1988 in the southern part of Lake St. Clair. Length–frequency analyses of populations from the Great Lakes and review of historical benthic studies suggest that the mussel was introduced into Lake St. Clair in late 1986, probably as a result of the discharge of ballast water from an...

Epidemiological criteria were used to examine the influence of environmental contamination on reproductive success of lake trout (Salvelinus namaycush,) in the Laurentian Great Lakes. Most of the information was obtained from lake trout eggs collected in southeastern Lake Michigan and reared in the laboratory. Two separate end points that measure reproductive success—egg hatchability and...

Despite the extensive urbanization of its watershed, the Detroit River still supports diverse fish and wildlife populations. Conflicting uses of the river for waste disposal, water withdrawals, shipping, recreation, and fishing require innovative management. Chemicals added by man to the Detroit River have adversely affected the health and habitats of the river's plants and animals. In...

Within the Federal government, the U. S. Fish and Wildlife Service (Service) has primary responsibility for legal and policy responsibility for introduced exotic species. The Lacey Act of 1900 authorizes the Service to prohibit the importation of species that are potentially injurious to native fish and wildlife. However, regulations under authority of the Lacey Act cover only a few...

Larval fish samples were collected in plankton tow nets in spring and summer, 1977–1978 and 1983–1984, in the St. Clair and Detroit rivers which are part of the connecting waterway between Lakes Huron and Erie. Larvae abundance of the major forage fish in the rivers are compared with their year-class abundance, as measured by bottom trawl catches of later life stages in Lakes Huron and...