Samples from seven locations at depths to 21 m, collected over periods of up to 8 years, were used to describe the nearshore distribution and abundance of burbot Lota Iota and deepwater sculpin Myoxocephalus thompsoni larvae in Lake Michigan. Based upon power-plant-entrainment samples and field collections, burbot larvae (3.0-7.5 mm) occurred from late March to mid-June, most abundantly in April and May, and most often at water temperatures of 6-12 C. Larvae were collected from the 0.5-to 13.5-m depth strata as far lakeward as the 2 l-m bottom contour, the limit of offshore sampling. In eastern Lake Michigan, highest densities (up to 843 larvae/ 1,000 m a) were at the 1-m contour; in Green Bay, up to 24,000 larvae/l,000 m a were detected near the Bark River. High densities of burbot larvae at bottom depths 3 m and less indicated inshore spawning and river spawning at some sites. Deepwater sculpin larvae first occurred in early February and were common in March and April entrainment samples. Larvae (8.0-22.0 mm) were in nearshore waters usually through May at depth strata of 0.5 to 17 m as far lakeward as the 18-m bottom contour. Most larvae occurred at water temperatures below 6 C. Field densities were low, 5 to 78 larvae/l,000 m a. Deepwater sculpin larvae were pelagic and were dispersed over great distances by currents.

Increases in plasma lactate and glucose concentrations, along with decreases in plasma chloride and liver glycogen concentrations, were observed in muskellunge in response to capture and handling. Holding muskellunge in 0.3% NaCl alleviated some of the physiological symptoms of stress, but holding the fish in the lake for 48 hr before release had no effect. Physiological responses to fin‐clipping and transport by truck were slight in comparison to that of original capture. Salt treatment and reduction in duration and frequency of handling is recommended.

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