Jul 21, 2002 4 min read

BUFFALO, N.Y. (AP) – Lake Erie once again is showing signs of an environmental crisis, after nearly two decades of mostly good news about the health of the lake. Environmentalists say a number of factors are again straining the most

vulnerable of the Great Lakes: a fourth straight year of large-scale fish and bird die-offs, a large “dead zone” off the Ohio shoreline and the threat of invasion by another non-native species with a voracious appetite.

“Lake Erie is like the canary in the coal mine,” said Margaret Wooster, executive director of Great Lakes United.

“It’s the most shallow and the most vulnerable,” she said. “It’s the one where we’re already beginning to see the signs we saw in the 1960s, only now we’re looking at a more diverse and complex set of causes.”

While pollution was at the root of the lake’s woes 40 years ago, lake watchers theorize that the current problems may be the proliferation of invader species like the zebra mussel, quagga mussel and the round goby.

“It’s possible – and this is still a theory – that the exotic species mixture is the real root of the problem,” said Bill Culligan, who heads the state Department of Environmental Conservation’s Lake Erie Fisheries unit in Dunkirk. “The gobies and the zebra mussels and the things that eat those two things are the ones being affected.”

The round goby and the zebra mussel have changed the lake, but lake watchers are bracing for another intruder they fear could be an even larger invader: the Asian carp.

Imported from China in 1973 to improve the water quality in aquaculture operations in Arkansas, the carp managed to escape those confines and multiply rapidly in the surrounding states’ rivers and lakes.

They have advanced into the Illinois River as far as Joliet, Ill., only 25 miles from Chicago. If they get that far, they will be at the Great Lakes’ door and, as Jerry Rasmussen of the U.S. Fish and Wildlife Service said, “I don’t think you want them.”

The larger types of Asian carp, the bighead and the silver, have an appetite that would put Homer Simpson to shame. They can weigh up to 100 pounds and grow to more than four feet long. Rasmussen has studied the carp as they moved up north along the Mississippi River.

Much of Lake Erie was anoxic, or oxygen-deprived, in the late 1960s, but after millions of dollars was spent on upgraded sewage treatment plants, that condition had been turned around.

Signs of a disrupted ecosystem became apparent on the lake in 1999, when scientists dissecting dead wildlife found along the lake shores discovered the animals were killed by type E botulism. Last found in some of the other Great Lakes in the 1960s, it had never been found before in Lake Erie.

The number of dead birds and fish mushroomed in 2000. Early in the summer, it was a large die-off of mud puppies, an aquatic salamander, on the Canadian shore, but as the year went on, larger creatures began floating up on the shoreline between Buffalo and Erie, Pa.

Some of the fish deaths can be attributed to natural causes or natural conditions, like thermal shock, which occurs when temperatures change too quickly for the fish to adjust. But DEC senior wildlife pathologist Dr. Ward Stone said many died from botulism.

This year, there has been another large mud puppy die-off, this time on the New York shore, as well as a large number of dead ring-billed gulls.

The bird die-off has come earlier than the previous two years, Stone said.

Stone believes the appearance of botulism is related to the invaders, the round goby and the quagga and zebra mussels.

“What I think is that the botulism started out in fish or mud puppies, and now it is going through by birds eating fly larvae” coming out of the decomposing fish and birds along the shoreline, Stone said.