Migratory Bird Flyways And Off-Shore Wind Farms:- A Co-Evolutionary Overlap
Why is it that sites with otherwise ideal characteristics often overlap migratory bird flyways - waterfowl mainly? Coincidence, or predetermined evolutionary outcome?
On Jan. 10, Green Energy Ohio released the first two years of data from an ongoing study in which wind over Lake Erie is being measured from a 165-foot tower on top of Cleveland's water intake crib. It's one of 10 monitors around the state but the only one that lies offshore. Not surprisingly, the strongest, most consistent winds were documented there, resulting in some excitement. The real test, though, will be in the Toledo area, where the wind-wildlife issue collides.
Northwest Ohio is seen by developers as the Great Lakes region's most ideal spot for harnessing wind, given its shallow water and proximity to urban areas.
It also lies in the path of two important migratory bird flyways [as pictured], so the issue is far from being settled.
Waterfowl which nest in Canada and migrate Southward for the winter not only follow optimal wind, they follow winds to traditional stop-overs (marshes, estuaries, and lakes) for food and shelter. They'll leave the Canadian prairie pothole region in late fall, just ahead of arctic air masses; and, in spring, reverse course - over the same flyways.
That the co-evolutionary selection pressure is identical for both migratory waterfowl, such as the Canvasback (pictured) and wind farm siting in the Upper Mid-West and along the coasts stems from the fact that wind blowing across open water creates less turbulence than hilly, or tree- and city-covered, land, resulting in a more laminar flow with higher average velocity. Good for migrating birds and for wind turbines.
This issue will not be resolved by re-engineering the turbines or by politics. Wildlife biologists will need to observe and measure the interactions of migratory birds and lake-anchored wind turbines, just as they have in Europe and for the proposed Cape Wind project.