Peggi Rodgers wrote:

>I was terribly disappointed this past summer when our resident flock of
>crows drove off a potential nesting pair of Red-tails. I've even seen them
>dash off in the direction of a hawk call. Think they do it for fun as well
>as profit?

They *have* to do it for fun, a hard admission from a person who believes
in adaptations =FCber Alles. A migrating Sharp-shinned Hawk, high overhead,
poses absolutely no threat to a crow, yet they will spiral up to meet it
and accompany it out of sight (or quickly drop back down, depending on crow
and/or mood).

Birds should chase other bird species for 3 reasons: (1) predators after
prey; (2) prey mobbing predators; and (3) aggression between two species
using a common resource. Although some crow chasing may fit in one or the
other of these categories, some of it doesn't seem to fit in any of them.
I'm left with *fun*. It seems much like something a bored gaggle of
primates would do.

Dennis Paulson, Director phone 206-756-3798
Slater Museum of Natural History fax 206-756-3352
University of Puget Sound e-mail dpaulson at ups.edu
Tacoma, WA 98416