Cormorants might just be the wolf controversy of the angling world. Many anglers see them as Terminator-like fish-eating machines, and cormorant control is always a contentious topic. Now the state of Michigan has proposed to double the number of cormorants it kills.
From this story on Interlochen Public Radio:
Michigan wildlife officials are pushing for more control of a fish eating water bird. They want to double the number of cormorants killed in Michigan each year, to about 20,000. Cormorants nest in colonies on islands in the Upper Great Lakes and Canada, and they can gobble up a lot of fish. But, some other researchers are not so sure killing more cormorants will mean more perch, walleye and bass for anglers. _Thirty years ago, the double crested cormorant was a poster bird for toxic contaminants like DDT in the Great Lakes. Wildlife biologists used to take live birds with crossed bills and other deformities to public meetings to press for cleanup of the lakes. Since then toxins have been reduced, and cormorant numbers have rebounded dramatically.
But that put anglers in an uproar about the large black duck-like birds. They charge cormorants are a plague on popular fishing grounds. Eventually, federal wildlife officials allowed about 10,000 cormorants to be killed in Michigan each year. Pete Butchko is the federal agent in charge of cormorant control in Michigan. He says he still hears cries to kill them all. “Some people may want Michigan to be cormorant free,” he says. “It’s just not going to happen. Cormorants are native and have a place here.” But what that place is continues to come up for heated debate. In the last six years, wildlife officials cut the number of cormorant nests in Michigan by about a third. They did it largely by shooting the birds and spraying vegetable oil on their eggs, to smother them.
An area they hit hard was the Les Cheneaux Islands in northern Lake Huron. It’s been a popular destination for perch anglers for decades. Dave Fielder, the lead fisheries researcher for the Michigan DNRE in that area, says as they knocked down cormorant numbers by 90 percent, he could see the fishery improve. People began catching more perch. “The Les Cheneaux Islands experience says at least in certain places there are real tangible benefits from cormorant control,” he says. But not all researchers agree with Fielder’s findings, including Jim Diana, a professor of natural resources at the University of Michigan and director of the Sea Grant program in the state. Diana says many other factors such as invasive species and changing water levels have contributed to fluctuating perch populations throughout the Great Lakes. But unlike those factors, he says, cormorants are highly visible. “And as a result now cormorants are being targeted for removal, I think without any good evidence that it’s going to have any effect,” he says._