Movements and Temperatures of Radiotagged Salmonines in Lake Ontario and Comparisons with Other Large Aquatic Systems

Abstract

We used six years of radiotelemetry data (1980–86) to compare movements and temperatures occupied by four introduced salmonine species (174 fish) in the nearshore region of Lake Ontario. Movement patterns (64% moved east initially with prevailing currents; 68% reversed direction one or more times), net movement rates (ave. −4.7 km/d), water temperatures occupied (ave. = 10.7 C) and harvest rates by anglers (ave. = 23% of radiotagged salmonines) were generally similar among species and seasons. However, Pacific salmon (coho, Oncorhynchus kisutch and chinook, O. tshawvtscha) moved against prevailing currents and were caught by anglers more often than brown trout (Salmo trutta) and rainbow trout (O. mykiss, formerly S. gairdneri). The movement patterns and thermal habitats of salmonines in Lake Ontario generally were in the mid-range of those reported for conspecifics in other large lakes and the North Pacific Ocean.