BY JEROME S. JOURDAN
The Great Lakes form a natural barrier to raptor migration. Thermals, or pockets of rising heat, provide buoyancy to raptors and vultures that allow them to soar for hours without flapping their wings. These thermals disappear over open water, thus requiring raptors to avoid open-water crossings as much as possible.
Migrating raptors from Canada are forced to pass to the west or east of the Great Lakes before heading south across the U.S. to their wintering grounds in Mexico, Central and South America. For those birds traveling the east around the Great Lakes the region of Gibraltar, Mich. and Essex, Ont. host some of the largest flights of raptors north of the Mexican border. [Read more…]