Quagga mussels from Lake Michigan.
The Quagga Mussel Experience: The Great Lakes’ Lessons for the West
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Joshua Dill: How and when did the quagga mussel invade the Great Lakes, and what have the effects been? Russell Cuhel: Both the quagga and the zebra mussel came from the Dnieper River in Ukraine. They were
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transported in the ballast water of transatlantic shipping that came up into the Great Lakes via the St. Lawrence Seaway, through the canals and locks, and ultimately into Lake Superior. It is likely that they were first discharged into the Great Lakes in 1988 or 1989. They made an appearance in Lake Erie shortly thereafter. Here in Lake Michigan, they did not appear until the early 2000s—2002 or 2003. They undoubtedly were in all the Great Lakes by 1990, but because each of the lakes is different in its structure and the way that water and people move around, they did not become established in each lake at the same time. Some areas, like Green Bay, had a much more rapid initial establishment of zebra and quagga mussels than did the main basin of Lake Michigan, but neither reached the fantastic population densities found in less sedimentladen water. We got a phone call in 2007 from the Metropolitan Water District in Los Angeles saying that they had quagga mussels in Lake Mead and Lake Havasu and asking for our advice. As far as we know, zebra mussels have not established themselves in California; quagga mussels were the first ones to get there. When people remove the visible mussels from the bottom of their boats, that is superficial at best. The real problem is the almost-invisible mussel larvae, known as veligers, that get into the cooling systems of boat engines. MUNICIPAL WATER LEADER
PHOTO COURTESY OF RUSSELL CUHEL AND CARMEN AGUILAR.
he quagga mussel is an invasive species that, over the last 30 years, has heavily colonized the Great Lakes. Its hydrodynamic, geochemical, optical, and ecological effects are so great that the species is termed an “ecosystemrevising organism” or “ecosystem engineer.” Now, quaggas are spreading to the rivers of California, Lake Mead, and other water bodies in the West—largely thanks to human enablers. Not only does the quagga affect water bodies from an ecological point of view, it can also pose major problems for irrigators and water suppliers. Russell Cuhel and Carmen Aguilar are scientists at the University of Wisconsin–Milwaukee’s School of Freshwater Sciences who have researched the quagga mussel from a biological and ecological point of view. They have also provided advice to water users in the West about how best to deal with the coming quagga invasion. In this interview with Municipal Water Leader Managing Editor Joshua Dill, Dr. Cuhel and Dr. Aguilar discuss the experience of the Great Lakes, particularly Lake Michigan, their area of firsthand expertise, and the lessons it can provide to the western states.
