Lake Waconia and its supposed problem with Double-crested Cormorants are back in the news. Perhaps you saw the article on the front of the Twin Cities/Region section of today’s (Friday) paper.
Briefly, city fathers and businesspeople in Waconia believe that fishing in their lake is down, and that the problem is caused by cormorants gobbling up so many game fish. There has been a lot of crying out there in Carver County, tears mixed with strong requests that cormorants be killed as a solution. Sharpshooters already have taken some cormorants, but the demand to kill kill kill continues.
Taking this to a ridiculous level was a request that two of Minnesota’s Congressmen, Kline and Peterson, seek federal assistance in this battle.
And so, always alert for ways to please voters, the two Congressmen did introduce a bill giving the state more control over this federally protected bird species. The bill actually got a committee hearing yesterday, all other concerns on which Congress might focus its attention apparently under control.
Science and reality have no place in consideration or comments from city fathers, and now from some of the testimony before a Congressional committee. No study has been done to determine if cormorants actually are reducing the Lake Waconia game-fish population. And if a study had been done it surely would have reached the same conclusions as dozens of other such studies: cormorants do not influence game-fish populations.
A fish-population survey done in 2010 by Minnesota DNR fisheries staff, showed perfectly normal game-fish levels in that lake. The report even absolves cormorants from any blame for any thing. All game species in Lake Waconia are in good shape, including the muskie population.
Introduced several years ago to add another dimension to fishing there, Lake Waconia muskies swim at the top of the lake’s food chain. Muskies, which grow to be three or four feet long or longer, eat whatever they choose. Studies by the Wisconsin DNR have shown that muskies choose very particular fish – smooth, soft-finned, fatty, high-protein fish such as sucker, tullibee, ciscoe, bullhead, carp, and various minnow species. Note: no game fish on that list.
Look at it this way: if a muskie, a huge predator with a mouth full of sharp teeth, chooses to eat smooth, soft-finned, fatty, high-protein (non-game) fish, why believe that cormorants make other choices? Animals do not behave inefficiently. Animals -- birds-- when making food choices consider energy spent and energy received. The cormorants are on the same diet page as the muskies.
Given a choice, wouldn’t you rather swallow a smooth fish with soft fins?
It's unlikely that the legislation pursued in Congress will move beyond yesterday’s House hearing. We can only hope that this silly business ends there.
Oh, yes: sharing the island nesting colony with the Lake Waconia cormorants are Great Blue Herons and Common Egrets. Both species eat fish. Both contribute to the guano that also seems to be a problem for Waconians. Strangely, no one is asking that herons or egrets be shot.
Not yet, anyway.