Deepwater Spawning by Lake Trout (Salvelinus namaycush) in Keuka Lake, New York

Egg deposition in deep water by a self-sustaining lake trout population is reported for Keuka Lake, one of the Finger Lakes of New York. Deep water spawning may be a critically important component to the restoration of lake trout in the Great Lakes. In 2002, spawning occurred on or about December 6 at a water temperature of 6.7°C at depths ranging from 24.6 to 27.7 m, with an average egg abundance of 1,318 eggs·m−2. The population, presumably the native strain, spawned on a steep slope (30-40°) on small shale substrate with little interstitial space. Abundance of egg predators was low and limited to slimy sculpins (6.9 sculpins·m−2). Early mortality syndrome (EMS), associated with an alewife diet-mediated thiamine deficiency in parents, was detected in larvae reared from the wild-caught eggs, but was of insufficient magnitude to eliminate natural reproduction in Keuka Lake.