David

There's a fairly large winter roost near the Mid-Hudson Bridge in Poughkeepsie, NY, about 10 miles south of me.  When the Hudson is frozen over, the pre-roost gathering spot seems to be on the river ice.  The crows must disperse over a fairly wide area during the day, because for about 2 hours in the mid to late afternoon we'll see a constant stream of crows over our house, flying south along the river to the roost.  There will almost always be at least one crow visible in the air at this time, and often a dozen or more, seemingly in loose groups.  We don't notice the same concentration of birds or arrow-straight flight in the morning, so they must be taking their time, wandering a bit, on the morning flight north. I have to say I love driving down past the roost just before dawn on winter mornings, seeing the crows covering the deciduous trees as thickly as leaves.  And I also love just standing outside watching them all fly south in the afternoon.  They're really quite beautiful birds.