Michigan Department of Natural Resources
Fisheries Research Report No. 2043, 1997
Factors Influencing the Year-Class Strength of Reef Spawned Walleye
in Western Lake Erie
Edward F. Roseman
Department of Fisheries and Wildlife
Michigan State University
East Lansing, Michigan
Abstract.-Variation
in egg and larval survival have been suspected to be principal sources
of walleye Stizostedion vitreum recruitment variability in Lake Erie.
I examined walleye egg deposition and survival and larval vital rates
in western Lake Erie in 1994 and 1995. Densities of eggs and larvae were
higher in 1994 than 1995. Growth of larval walleye was greater in 1994.
Larval densities were greater at western sites in 1994 and greater at
eastern and south-eastern sites in 1995. Slow water warming rates and
frequent intense winds contributed to the low density and survival of
eggs on reefs in 1995 by prolonging incubation periods and increasing
the vulnerability of eggs to mortality factors. Optimal year-class strength
could result with precisely timed events providing high egg densities,
fast water warming rates and few wind storms in spring providing good
egg survival and high larval densities.