Nutritional Quality of Foods Consumed by Gizzard Shad in Western Lake Erie

Gizzard shad (Dorosoma cepedianum) were collected from four locations in western Lake Erie during summer, 1982. The nutritional quality of foods ingested by these fish was examined. Small (<60 mm standard length), age 0 fish consumed mostly zooplankton with high organic (>80% of dry weight) and nitrogen (>6% of dry weight) contents. The phytoplankton and detritus diets of larger, age 0 and adult gizzard shad were of poorer nutritional quality (organic = 10-30%; nitrogen = 0.7-3.1% of dry weight). However, the nutritional quality of these foods was apparently adequate for gizzard shad, as most fish from all locations exhibited good condition and rapid growth rates. Observed differences in size and condition of age 0 gizzard shad among the collection sites may be due, in part, to variation in the quality of foods consumed during the growing season. OHIO J. SCI. 88 (3): 110-113, 1988