Out-of-Water Survival

From October, 1995 (Update #25)

Successful zebra mussel colonization via overland dispersal requires that the bivalves survive out of water for extended periods. While boaters' guides recommend keeping boats dry-docked for up to two weeks to kill any attached zebra mussels, most available information has been anecdotal or lacked specific information about air temperature or relative humidity. In the March 1995 issue of the Canadian Journal of Fisheries and Aquatic Sciences, McGill Univer-sity's Anthony Ricciardi, Robert Serrouya and Frederick Whoriskey address the subject in some depth. The authors exposed zebra mussels of two size classes (10-18 mm and 21-28 mm) to controlled temperature and humidity conditions. At 30 C, all mussels were dead within three days. At lower temperatures mussels were able to survive for a longer period, depending upon the relative humidity at which they were held. At 20 C, all the mussels died within three to five days at 10 to 50 percent relative humidity, though some mussels were able to survive five to six days at 95 percent relative humidity. At 10 C some mussels were able to survive for up to 10 days at high humidities. No mussels survived under any conditions after 15 days out of water. Quagga mussel survival rate at 20 C was lower than that of zebra mussels, suggesting that quagga mussels are less likely to survive overland transport. The authors concluded that given average summer temperature conditions, zebra mussels could survive an overland trip within a five-day period of removal from infested waters.

ID: 199510-2.

The Zebra Mussel Update was a 4- to 8-page quarterly national newsletter published by the University of Wisconsin Sea Grant Institute from May 1990 through May 1997. The ZMU documented the spread of the zebra mussel -- an exotic nuisance mussel -- through North America's freshwater environments, especially the Great Lakes, and on efforts to control it.