Comparing cisco egg size among three Great Lake populations

Session: Poster Session

Scott Koenigbauer, Purdue University, [email protected]
Tomas Hook, Purdue University, Dept. Forestry and Natural Resources, [email protected]

Abstract

The size of a fish egg is often correlated with both its energetic content and its probability of survival. Due to limited energy and ovary capacity, female fish face a trade-off between egg size and fecundity, as increasing egg quantity leads to a decrease in egg size. Environmental and ecological factors that affect offspring survival, such as habitat type, temperature, and fish densities, may affect a population’s average egg size. Intraspecific variation of average egg size has been observed among populations of Great Lakes fish.

Cisco (Coregonus artedi) are a native Great Lakes species of economic and ecological importance, but have declined over the past century. Thus, their populations’ reestablishment is a common management goal across the Great Lakes. Differences in ecosystems and abiotic factors may affect the mean egg sizes of cisco populations. To examine this, we compared the relationship between maternal length and average egg diameter among cisco stocks in Lake Huron, Lake Michigan and Lake Superior. Egg samples have been collected with associated maternal length data, stored in ethanol and measured to compare among populations. Findings from this study could inform population rehabilitation efforts by elucidating differences in reproductive strategies among stocks.

Twitter handle of presenter
@skoenigb