It seems the Militia Hill Hawk watchers that gather at Fort Washington State Park are having an exciting year.
This year’s migration is proving the best year ever. By September 23, more than 20,000 birds of prey flew over the park in the annual migration southward. Ninety-six Bald Eagles were among the travelers.
For the first few days of this past week, it was rainy and cloudy outside. Rain systems bring winds from the South blowing northward. This is not good south-going, migration weather. The birds will wait for clear skies and wind blowing from the north to the south to resume their journeys.
On a clear day thermals (columns of warm air) rise up from the ground (including roads and parking lots). Raptors which migrate during the day, can coast on the columns of warm air for miles without flapping their wings. Songbirds tend to migrate at night when there are no thermals.
As fascinating thing about thermals – they can often have a cumulus cloud sitting above them. Wikipedia has a good illustration of this phenomena. On the next clear day I will be looking for a line of cumulus clouds pointing the way south. I guess there will be raptors riding the thermals beneath the cumulus clouds. Earth is just too cool.
With rough weather, migrating raptors will head west toward the Appalachian mountains and continue southward.
This past week has been the first time I have been able to get out and migration-watch. The last several weeks with school starting have been tiring and busy.
Migration will last a few more weeks. The Militia Hill Hawk Watch lasts from September 1st through October 31st. We still have a little time left to enjoy the spectacle.