The growth, diet and distribution of yellow perch fry, Perca flavescens, in Lake Itasca, Minnesota

The growth, diet, and distribution of yellow perch fry, Perca flavescens (Mitchill), were determined from fry collected during the summers of 1978, 1979, and 1980 from Lake Itasca, Minnesota. Yellow perch hatched in the littoral zone at 5.5-6.0 mm total length. Within two weeks all fry had moved into the limnetic zone, where they remained until reaching a length of approximately 25 mm; at this time they moved back into the littoral zone. During the first 40 days after hatching, perch fry grew in length approximately 0.50 mm per day. Growth rates for the remainder of the summer were lower, averaging approximately 0.43 mm per day. Fry first fed at 9-10 mm in length on a diet composed of copepod nauplii, immature copepodids, and rotifers. Various stages of copepods remained the dominant food item \antil the fry reached 20-24 mm in length, at which time cladocerans became the domincuit prey. Larger food items, such as insects ;and amphipods were important in the diet of fry greate