Food of Pelagic Young of the Walleye,Stizostedion vitreum vitreum, in Oneida Lake, New York

Publisher Website
Google Scholar
Abstract
Food of walleye larvae in Oneida Lake during the first 6 weeks of life in 1961–63 consisted mainly of copepods supplemented by cladocera and fish. As walleye larvae grew from 7.0 to 24.0 mm in length they ate larger food organisms. More fish were eaten during 1962 than 1961 or 1963. Of the crustacean food the copepod, Epischura, was more common in 1961 stomachs than in 1962 or 1963. Feeding commenced before complete absorption of the yolk reserves. For the three years, 31% of the sac fry contained food while 91% of the post‐yolk sac fry had fed. Although zooplankton was more abundant in the plankton samples of 1962 than in those of 1961 or 1963, the number of food items in stomachs of fry was nearly the same each year. Abundance of zooplankton food organisms and walleye larvae were positively correlated at five of six stations sampled in 1962 while the sixth station had the fewest fry yet most abundant zooplankton. Walleyes generally ate copepods in proportion to their abundance in the plankton. Cladocera were negatively selected on dates when fry and plankton samples were available. Among the copepod genera, Epischura was positively selected while Diaptomus was negatively selected. Cyclops was positively selected when Epischura was rare in the lake plankton but was negatively selected when Epischura became common.

This publication has 1 reference indexed in Scilit: