The effect of zebra mussel colonization on native snail species of Douglas Lake in northern Michigan.

Abstract

The introduction of invasive species has caused extensive ecological and economic damage in freshwater ecosystems. In the Great Lakes region, zebra mussels (Dreissena polymorpha) have outcompeted native mollusks and driven many species towards extinction. They cause over $200 million of damage to the Great Lakes region annually. This study was performed to analyze the effect of zebra mussel colonization on native snail species of Douglas Lake in Northern Michigan. Four snail species: Campeloma decisum, Elimia livescens, Planorbella campanulata, and Stagnicola emarginata were collected with and without zebra mussels from South Fishtail Bay of Douglas Lake. The zebra mussel likelihood of colonization and horizontal movement as a measure of fitness were analyzed per species for differences between snails with zebra mussels and without. Our research showed that C. decisum and E. livescens were colonized most frequently. In addition, zebra mussel load was found to have a negative effect on horizontal movement of all snail species. Based on these results, our study concluded that zebra mussels have a significant negative effect on native snail species of Douglas Lake in Northern Michigan.