Raptor Wednesday

A crop of Cooper’s!

These were all seen on the same day recently in Green-Wood. Four sightings, I think of three individual birds, but possibly four. I inadvertently flushed the first (seen in first two photos). It was hiding in an evergreen thicket; I didn’t see the bird until it flew out and landed nearby. Note that bulbous throat: that’s the bird’s crop, and it’s stuffed with food. The Coop was digesting when I stumbled upon it. The bulging crop is quite pronounced on this specimen. The crop is an enlargement of the esophagus, used to store food before digestion. There’s only so much room in the gut, after all, so raptors, who depend on high-energy protein meals, can stuff themselves silly when there is available prey. Of course, all that meat slows you down. The birds therefore take cover or otherwise lay low while they’re digesting.This bird, seen a few hours later perched out in the open, doesn’t have nearly as full of a crop. In fact, I didn’t even notice it until the bird took wing; then it was obvious, although not nearly the I-swallowed-an-apple of the first bird. A smaller morsel or just more digestion time? While I was observing this bird, another Cooper’s flew right overhead; I expected this one to respond, but neither seemed to notice each other (nor, curiously, did two Blue Jays briefly in this same tree). Note the flecks of blood on the feathers just above the talons. Also, compare the eye color of these birds. As Cooper’s age, their eyes turn from yellow to orange to red (most pronouncedly in the males). I was scanning for owls when I stumbled upon yet another Coop, not so far from the first sighting, but four hours later. Also with a full crop. Maybe this is why songbirds have been so scarce in Green-Wood this winter?

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