Species Regional Summary
Dreissena polymorpha
_CDA_L071 (Saginaw River) ( L071 )

Vectors

Level	Vector
Alternate	Ballast Water
Alternate	Hull Fouling
Alternate	Natural Dispersal

Regional Impacts

Ecological Impact		Herbivory
By 1992-1993, the biomass of Zebra Mussels in inner Saginaw Bay, Lake Huron, had a filtering capacity of 0.2-1.2 X the volume of the inner Bay per day. Chlorophyll and suspended solids were greatly reduced, and the decreased reflectivity (increased transparency) of the water was detectable by satellite imagery (Budd et al. 2001). Filtration by Zebra Mussels was selective - mussels ingested small, desirable flagellates, while rejecting large colonies of toxic Microcystis cyanobacteria in Lake Saginaw water (Vanderploeg et al. 2001).
Ecological Impact		Habitat Change
Filtration of the water by Zebra Mussels in inner Saginaw Bay, Lake Huron, resulted in greatly increased transparency and light penetration of the water, within 2-3 years after the initial invasion (Budd et al. 2001).

References

Budd, Judith W. (2001) Remote sensing of biotic effects: zebra mussel (Dreissena polymorpha) influence on water clarity in Saginaw Bay, Lake Huron., Limnology and Oceanography 46(2): 213-223

Vanderploeg, Henry A. and 6 authors (2001) Zebra mussel (Dreissena polymorpha) selective filtration promoted toxic Microcystis blooms in Saginaw Bay (Lake Huron) and Lake Erie, Canadian Journal of Fisheries and Aquatic Science 58: 1208-1221

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