For decades, exotic species have been invading the Great Lakes and mixing up the ecosystem. A few years ago the constant changes led to the collapse of the food web in Lake Huron. That event has gotten people interested in restoring native fish with the hope that they’ll be more stable, but as Peter Payette reports, not everyone wants the food web in the Great Lakes to look exactly like it did a century ago.
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Once upon a time, every Great lake was stuffed with lake herring. Trout would feast on them and so would people all over the Midwest, sometimes smoking or pickling the white flaky meat. Herring can grow more than two feet long. Every year commercial fishing nets would haul tens of millions of pounds of herring out of the lakes.
Fisheries biologist Mark Ebener says herring, or cisco, would lay so many eggs in the fall it was a food source for other fish. Ebener says it still is in Superior.
“You go into parts of Lake Superior in December and the whitefish are just gorged on cisco eggs.”
But herring largely disappeared from the lakes in the middle of the last century for a variety of reasons including overfishing. Biologists like Mark Ebener thinks restoring the fish should be a top priority. He’s with Chippewa Ottawa Resource Authority. It’s a tribal fishing agency based in Sault Ste. Marie. Some Michigan tribes have commercial fishing rights on the Great Lakes that date back to treaties signed in the 19th century. They’d like the states to be more aggressive about restoring native species. Ebener says if we want a stable ecosystem in the lakes, herring are crucial.
“It was the prey species. So if you want to restore the connectivity of the lakes and the historic predator-prey dynamics, why would you ignore herring”
While nobody would admit to ignoring the fish, figuring out exactly what happened to lake herring has not been a priority, but that’s changing.
Grand Traverse Bay is the only place herring are still known to breed in Lake Michigan. State fisheries biologists have been coming to this breeding ground near Elk Rapids for three years. The Department of Natural Resources and Environment wants to know why this remnant population doesn’t expand. Randy Claramont is the team leader. He says the primary suspect is an invasive fish that eats new born herring. They just picked one up in the net.
“There’s our predator. There’s a rainbow smelt. Right in where the cisco are, we also got an adult rainbow smelt.”
It’s not likely that a large scale effort to restore herring as the main prey fish in Lake Michigan would have universal support. That’s because the state is also responsible for managing the lake’s popular salmon fishery. Salmon are not native to the Great Lakes but are generally considered to be the most exciting sport fish to catch. Lots of anglers come up north to do this, so politically speaking, the salmon has clout.
Jim Dexter, the Lake Michigan basin coordinator for the Michigan DNRE, doesn’t think salmon like to eat herring.
“One thing that’s important to remember is that if you have a huge herring population, I don’t think you’ll be able to maintain the type of salmon sport fishery that we currently have.”
But it’s a different story in Lake Huron where the salmon disappeared in 2004. That was after the food web, dominated by exotic species, crashed. The upheaval has sparked interest in rebuilding a more stable ecosystem, and that’s why the Michigan Steelhead and Salmon Fishermen’s Association actively supports efforts to reestablish the herring in Huron. The state planted 40,000 herring there last year. Managers of the project think they’ll need to plant a million fish a year for a number of years to reestablish the species in the lake. That would cost millions of dollars.
For the Environment Report, I’m Peter Payette.