James H. Johnson
B.S. (Fisheries Management), University of Wisconsin-Stevens Point, 1973
M.S. (Fisheries Science), State University of New York (SUNY) College of Environmental Science and Forestry-Syracuse, 1978
Ph.D. (Fisheries Science), SUNY College of Environmental Science and Forestry-Syracuse, 1993
Anthropogenic activities have greatly impacted fish populations in the Great Lakes. Of all the Great Lakes, fish populations in Lake Ontario have been impacted the most severely, including the extirpation of Atlantic Salmon (Salmo salar) and deepwater coregonids such as bloater (Coregonus hoyi) and major declines in lake sturgeon (Acipenser fulvescens), deepwater sculpin (Myoxocephalus quadricornis), lake herring (C. artedi) and American eel (Anguilla rostrata). Loss of spawning habitat and perhaps overfishing are thought to be the major causes for the loss of Atlantic salmon and lake sturgeon, whereas invasive species such as alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordox) are considered to have led to the decline of coregonids, and deepwater sculpin. Because of the complexities associated with the extirpation or decline of native fish species in the Great Lakes there is no single remedy suitable for the restoration of all species. The restoration of deepwater coregonids, as well as extirpated Atlantic salmon, must at least initially rely on hatchery reared fish.
The objectives of this study are to (1) determine the annual diet composition of double-crested cormorants in eastern Lake Ontario and the St. Lawrence River, (2) estimate the number of fish consumed annually by cormorants in eastern Lake Ontario and the St. Lawrence River, and (3) evaluate the effectiveness of different management actions in reducing fish consumption.