Diet of Chinook Salmon in Eastern Lake Michigan, 1991-93

Abstract.–In recent years, a decline in chinook salmon Oncorhyncus tshawytscha abundance in Lake Michigan has been attributed to declining forage availability, increased incidence of bacterial kidney disease (BKD), as well as an interaction between these factors. Concern has also been expressed about the alewife Alosa pseudoharengus population's ability to support higher stocking levels of salmonines in the lake. Given these concerns, and the potential biases involved in evaluating chinook salmon diet using sport-caught fish, we conducted a study to evaluate the diet of chinook salmon in eastern Lake Michigan. Graded-mesh nylon gill nets were used to sample chinook salmon. Sampling was designed to determine the influence of chinook salmo