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.

Yellow perch were studied as a portion of a total environmental baseline study in 1972 before operation of a new pumped storage power plant on the eastern shore of Lake Michigan near Ludington. Of 1,546 perch taken by gill nets, age III (1969 year class) and IV fish contributed 40.1% and 27.4% of the total number, with male fish being taken much more frequently than females in all age classes during spring sampling. Comparative growth and lengthweight data indicated that the perch were generally growing to larger sizes than those reported previously from the Great Lakes. Most fish older than age I were sexually mature and spawned in shallow littoral waters from mid-May to late June. Mature fish spent the summer in the littoral zone and moved to deeper water by late fall. The ratio of ovary weight to body weight was 20-25% before spawning, declined sharply, and increased again in fall. Ninety-six female fish examined for fecundity had a range of 10,654 to 157,594 eggs, and in general, because of the larger sizes of the fish, had greater fecundity than previously reported for other yellow perch. Regression equations were developed for fecundity vs. length (logarithmic), weight (linear), ovarian weight (logarithmic), and age (semi-logarithmic). •Based on a portion of a thesis submitted to the facuky of the Department of Fisheries and Wildlife, at Michigan State University in partial fulfillment for the degree of Master of Science. 2 Michigan Agricultural Experiment Station Journal Article Number 7370. s Present address: Michigan State University, Department of Fisheries and Wildlife, Great Lakes Research Laboratory, South Lakeshore Drive, Ludington, Michigan 49431. relationships, spawning activity, reproduction, and fecundity, and uses of morphometric measurements as predictors. METHODS The year was arbitrarily divided into the following three periods, which tend to coincide with physical changes in climate at the sampling site: Spring, , with experimental gill nets consisting of seven 15.24-m panels of 25, 51, 64, 76, 102, 114, and 177 mm stretched mesh. Nets were set at five stations near the breakwater and jetties of the Ludington Pumped Storage Power Plant located about 7.5 km SSE of Ludington, Michigan, and at a control station about 7.5 km farther south of the plant. The control station was sufficiently far from the power plant that the effects by plant operation would be negligible. However, after an examination of the data no significant differences were found between stations and data from individual stations were pooled.Weather permitting, the six stations were sampled weekly with the nets set for 24-h periods. Generally, the bottom in the sampling area was composed of sand interspersed 726

Longnose dace taken mainly during night hours over gravel‐rock substrates in a surge zone of east‐central Lake Michigan provided seasonal data on distribution, age, growth, maturity, fecundity, and food habits. Dominated by age‐classes II and III, longnose dace entered surge‐zone waters in mid‐May for spawning and remained in small numbers through November. Peak spawning occurred during late June and early July. Egg production ranged from 870 to 9,953 eggs per female. Age 0 fish were taken in early August and reached a mean length of 42 mm by late October. Only a few yearlings (age I) spawned the following year; all fish were mature by age II. Major foods of adult fish were from terrestrial sources.

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