>In response to Skip Russell's comments about small size and beach-living in
>crows, perhaps the Fish Crow can be used to support the hypothesis,
>although I realize it has a wide range in the interior as well. One
>thought-do crows evolve smaller size where they coexist with ravens, which

Or ravens -- good point -- I'd forgotton about them. I wonder if there
are populations of similarly small Crows in the interior? There is an
isolated small pocket of Crows in the Catlow Valley in southeast Oregon,
deep in the heart of Raven Country. They seem to be small, but perhaps
that is because I have always had to look through so many Ravens to find
them.

Incidently, I used to live in St. Louis where Fish Crows were rather
common. Even though it is in the interior of the continent, Fish Crows
were almost always found near large rivers and lakes, and foraged along
the shoreline, just as they do along the coast.

>they do on the NW coast? I would think they would evolve |larger| size
>where they coexist with gulls, which seem to dominate them in most
>interactions.

I would expect just the opposite -- that small size would translate to
more agility in competing for scraps left by gulls, or in grabbing food
and getting out before being chased away by gulls. Also there would
presubably be less overlap in the range of food sources suitable to both.
Try to imagine a Crow swallowing a starfish!

Skip