Feds Find Fewer Fish Eggs Affected by Fungus in Mussel-Infes

ted Water

From October 11, 1991 (update #11)

ANN ARBOR, Mich. - An unexpected and apparently beneficial effect of zebra mussels on walleye egg survival was noted in a recent progress report from the U.S. Fish & Wildlife Service's Great Lakes National Fisheries Research Center at Ann Arbor. Preliminary results from controlled laboratory studies - 75% complete at the time of the report - on the effects of zebra mussels on walleye egg development and survival indicate that "surprisingly...walleye egg survival may be better in treatment tanks, where substrates are heavily colonized by zebra mussels, than in control tanks, where substrates are clean." The authors note that "fungus infestation on walleye eggs incubating in control tanks (clean substrates) are higher than in treatment tanks (substrates infested with zebra mussels), suggesting that zebra mussels may in some way be controlling the rate of fungal infestation of walleye eggs. Microhabitat water quality is different in control and treatment tanks. Oxygen levels are lower and ammonium levels are higher in substrates infested by zebra mussels than in clean substrates.".

ID: 19911011-9.

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.