Subject: [Tweeters] Heron and frog
Date: Mar 28 20:32:33 2010
From: Guttman,Burt - GuttmanB at evergreen.edu


In response to my tale of the heron and the frog, Dennis Paulson wrote, "I wonder if the frog was alive. Herons and other birds that eat relatively large prey very often spend quite a bit of time manipulating (and mandibulating) their prey, and I have always thought this was to kill it or at least greatly reduce its squirmability." I did wonder about that. The heron was squeezing the frog quite a lot with its powerful bill, and it may very well have been crushing the frog's guts, maybe even stopping its heart. Early in the battle, as the heron sometimes dipped the frog in the water, the frog seemed to kick a little as if trying to get away, but by the time the battle was over it was moving very little, if at all. This is an interesting question, and if anyone knows anything more about the details of feeding by herons or other birds that eat large animals, I'd love to hear about it. I've checked the books on my shelf that might be relevant and find nothing, though John Terres (Audubon Encyclopedia of N. A. Birds) notes that birds sometimes choke to death by trying to swallow something too large and that herons have done it by trying to swallow too-large fish.

Burt Guttman
The Evergreen State College
Olympia, WA 98505 guttmanb at evergreen.edu <mailto:guttmanb at evergreen.edu>
Home: 7334 Holmes Island Road S. E., Olympia, 98503