Charles R. Liston

Density and Distribution of Larval Fishes in Pentwater Marsh, a Coastal Wetland on Lake Michigan

In order to better understand the importance of a Great Lakes coastal marsh on fish production, the fish larvae of Pentwater Marsh, a drowned river-mouth wetland on Lake Michigan, were studied over a 3-yr period. Fish larvae were sampled at night by push nets in the channels and bayou-mouths and drop nets in the shallow, vegetated bayous of the marsh. Larval fish diversity and abundance were highest in 1984, perhaps due to more stable temperatures, higher water levels, and/ or increased submerged vegetational cover. In all years, carp (Cyprinus carpio) dominated the catch with marsh-wide densities of up to 30 larvae/m3. Subdominant species included sunfish (Lepomis spp.) and various minnows (Cyprinidae). Eighteen taxa were identified. Larval fish densities were 2 to 100 times higher in the shallow-water bayous than in the bayou-mouths and river channels. Larval fish densities were generally higher than documented for other wetland areas. However, previous studies may have underestimated densities since shallow-water sampling was not included and they were conducted during years of low water level. Coastal wetlands likely harbor greater numbers of young fishes than previously reported, emphasizing the importance of such areas to the ecology of the Great Lakes.

Age, Growth, and Fecundity of Yellow Perch, Perca flavescens, in Lake Michigan near Ludington, Michigan

Abstract 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 length-weight 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 ...

Life History of the Longnose Dace, Rhinichthys cataractae, in the Surge Zone of Eastern Lake Michigan Near Ludington, Michigan

Abstract 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.

Survival Following Exposure to Subzero Temperatures and Respiration in Cold Acclimatized Larvae of Enallagma boreale (Odonata:Zygoptera)

Larvae of Enallagma boreale survived exposure to -1.0° C (53%) and -4.0° C (10%). Ability to survive was not related to rate of cooling or duration of exposure. Respiration rates ranged from 0.10 ml O2/g/h at -1.0° C to 0.92 ml O2/g/h at 30.0° C. At -1.0° C the respiratory quotient of larvae was 0.72, indicating lipids were being metabolized. Calculated metabolic costs for the overwintering period were 40.5% of total body calories. It is suggested that overwintering frozen into ice at moderately cold temperatures may be energetically advantageous.

Age, Growth, Maturity, and Seasonal Food Habits of Round Whitefish, Prosopium cylindraceum, in Lake Michigan near Ludington, Michigan

Abstract Round whitefish were studied in 1972 and 1974 as a portion of a broad ecological study of a near-shore area of eastern Lake Michigan near Ludington, Michigan. Of 690 fish taken by gill nets, Age III fish were predominant in 1972 and Age IV in 1974. Male and female fish were taken in approximately equal numbers. About 50% of Age II and 90% of Age III fish were mature. Comparative growth and length-weight data indicated that the round whitefish were larger at any given age than those from previously reported populations. On a seasonal basis, benthic insect larvae and small mollusks were the organisms most frequently ingested.

Seasonal Abundance of Planktonic Rotifers in a Nearshore Area of Central Lake Michigan

Thirty-four species of planktonic rotifers were recorded from east central Lake Michigan. Polyarthra vulgaris and Keratella cochlearis were the most abundant species recorded. Kellicottia longispina, Notholca squamula, Keratella earlinae, K. quadrata, and Synchaeta stylata were also important species. Maximum abundance occurred in June (360 Ind./L). July and August abundances exceeded 100 ind./L while spring and fall samples contained 10-20 ind./L. The species assemblage in east central Lake Michigan, western Lake Michigan, and Lake Ontario is similar. The eutrophic indicator Brachionus, abundant in western Lake Erie, was rare in this investigation.

The Bioeconomic Impact of Impingement and Entrainment on Yellow Perch in Lake Erie

Abstract This study assesses the bioeconomic effects of the J. R. Whiting power plant on the yellow perch (Perca fiavescens) sport fishery in the Michigan waters of western Lake Erie in Monroe County. The surplus production model was applied to yellow perch commercial and sport catch-and-effort data. The model estimated the yellow perch population in the Lake Erie waters of Monroe County to be approximately 1.074 x 10 10 fish. The Leslie matrix, a density-independent mathematical model, then simulated the effects of impingement and entrainment by the J. R. Whiting plant on this population over the plants 50-year life expectancy (1952-2002). The combined effect of impingement and entrainment represents an estimated annual reduction of 1.7% in the size of the yellow perch population. Assuming that a 1.7%-reduction in population size will cause a 1.7%-reduction in the sport catch rate of yellow perch, a computerized simulation model of Great Lakes angling demand and supply was used to estimate the net econo...