Ospreys are relatively rare in this part of the state.  The nest on Big Muskego Lake is one of only three documented Osprey nests in the southeast Wisconsin region.  Ospreys are sometimes confused with bald eagles but can be distinguished by their smaller size, dark cheek patch, and narrower, angled-back wings.  These raptors hover over water and plunge feet first to catch fish with their sharp talons.  Ospreys that breed in the Upper Midwest spend winters near the equator and migrate back north to breed during the summer after reaching sexual maturity at three years of age.  Ospreys were changed from endangered status in Wisconsin in 1972 to threatened in 1989, and delisted in 2009.  Discontinued use of organochlorine pesticides, like DDT, is thought to be responsible for the Osprey's comeback. 

Following the restoration of Big Muskego Lake in 1997, a project was started to reintroduce Ospreys to the lake.  In 2003 adult Ospreys were observed around Big Muskego Lake.  Ospreys first successfully nested in 2005, hatching and fledging one young.  They had two young in both 2006 and 2008.  The future looks good for the local Osprey population - as young hatched here should "imprint" on the area and return to nest as adults.


Tracking Study of a Muskego Osprey (Ethel) / Ethel's Migration Route Map