PORT CLINTON — Researchers who study Lake Erie think toxic algae blooms that have fouled the water in recent years will continue to cause a drop in the number of walleye and perch in the lake.
That could deal a big economic blow to northern Ohio towns along Lake Erie that depend on tourists who come to catch the prized sport fish.
Invasive species like white perch and other fish that thrive in warmer water already are growing in numbers, said Roger Knight, administrator of the Lake Erie Fisheries Program within the Ohio Department of Natural Resources.
Walleye and perch will suffer as a result, he told The News-Herald of Port Clinton.
“We’re probably not going to lose them, but they’ll drop in abundance,” he said. “The fish have been through this before.”
A report released by the National Wildlife Federation in October blamed both excessive nutrients and invasive mussels that rob fish of food for the sharp drop-off in Great Lakes fish.
The algae bloom this summer in Lake Erie, the shallowest and warmest of the lakes, was worse this summer than any time in recorded history, the report said.
The lake suffered from similar algal outbreaks in the late 1960s and early ’70s until new environmental regulations led to a cleaner lake.
“Honestly, I didn’t think that was going to be possible,” said Jeff Reutter, Ohio Sea Grant program director. “But we did it, and the lake responded by becoming the walleye capital of the world.”
He said the lake can recover again if efforts are made to reduce how much phosphorus flows from agricultural runoff and sewer-treatment plants.
“If you figure if nothing changes, next year will be worse than last year,” he said. “A lot of us are hoping that this year was an anomaly.”
Steve Davis, a Natural Resources Conservation Service watershed specialist, said it won’t be easy.
“It’s going to take a lot of work to reduce it. Most of the agricultural community is trying to do a good job,” he said.
Farmers are using new methods — such as using a spreader that and skips areas that already have enough fertilizer — to cut down how much phosphorus runs into the lake and its tributaries, Davis said.