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09/08/2001 "Bird migration slow at the moment"
No birding today because of the southerly winds which has allowed for a summer-like day, with temperatures in the mid-80's along with higher humidity.
The winds need to be out of the north for the passerines - songbirds - to make their Lake Erie crossing which is normally done at night and thus, providing good birding the following morning.
The raptors funneling down from Canada around the Great Lakes and crossing into the U.S. just south of Detroit also need northerly winds. Raptors don't cross water because they rely on thermals - rising pockets of warm air - caused by the heating of the ground which means they obviously migrate during the day.
Thunderstorms have been occurring in the area since this afternoon so maybe a cold front will be moving through and causing the winds to switch to the north-northwest. I will check the maps later. Sunday afternoon could be good for raptors.
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