Buffalo, NY (WBEN) A number of fish have been washing up dead on the Lake Erie shoreline in the last week or so. It turns out to be a species of fish that can't tolerate cold weather.
Jim Markham of the DEC says reports started coming in last week of a lot of fish washing up on Lake Erie's shores. Those fish are alewife. "Alewife populations in Lake Erie in recent years have been expanding quickly due to the warm winters that we've been having. However, alewife are a cold, intolerant species, and in the prolonged ice cover that we had on Lake Erie actually caused them, caused a mass mortality in them this year due to the cold," explains Markham. He says these have been happening before, but notes the magnitude of the fish kill event this year is much higher than in the past, because of the high biomass and numbers of alewife that out on the lake this year
Markham says alewife go to the bottom of the lake during winter months. "Then there's a phenomenon most people think that the densest water is 32 degrees, but it's not. It's actually 39 degrees, frozen water 32 degrees is at the top, and your 39 degree water is at the bottom. And in years with little ice cover, or no ice cover on the lake, which we've had and for at least six years now, on Lake Erie, those fish are able to go to the bottom and survive." But he says this year was a different story. "Prolonged ice cover caused the water temperatures to drop all the way down on the water column, and it finally reached the point where they could not survive those cold temperatures any longer causing our mass mortality event that was underneath the ice pack."
Markham says he does not foresee this being a problem at all in terms of available forage fish, or having any effect at all on sport fish species. "Lake Erie is blessed to have a wide variety of forage fish available, including rainbow smelt, Rainbow Goby, emerald shiners and small gizzard Chad that are available for our sport fish species and an alewife are are not typically a fish that we see come up in the fish diets a lot," adds Markham. "They have been increasing in recent years, just because their numbers have increased so much. But it's not typically something that we see in our in our fish diets at all. So I am not expecting to see any consequences of this."
Markham says it appears to be just alewife this year, but if shoreline residents or any beach walkers are starting to see other species start to turn up, that is certainly something the DEC will be interested in checking out.
