Contiguous Backwater Lakes as Possible Refugia for Unionid Mussels in Areas ofHeavy Zebra Mussel ('Dreissena polymorpha') Colonization. Long Term Resource Monitoring Program

摘要

Swan Lake, a backwater of the Illinois River, had a smaller population of zebramussels (Dreissena polymorpha) in 1994 compared with 1993. This reduction in mussel abundance may reflect the controlling influence of lake physical properties and interactions between waterflow, freshwater drum, and D. polymorpha. Because this lake is inhabited by a diverse unionid fauna (at least 16 species) but by relatively few D. polymorpha, it could function as a refugia for native mussels from the adverse effects of D. polymorpha.