>I am looking for information regarding hybridization of finches. In
>particular:
>Cassin's Finch (Carpodacus cassinnii) and Purple Finch (Carpodacus purpureus).
>We have banded hundreds of these species at our home in Leavenworth, WA and
>have
>found several individuals that exhibit characteristics half-way between the
>two.
>These two species are morphologically similar, but some individuals are
>virtually impossible to tell apart in the hand, let alone while in the field.
>Has anyone noticed this potential for hybridization before? I would be
>interested in looking at banding data from others who have banded large
>numbers
>of these finches, escpecially in Eastern Washington where we have a overlap of
>these two species. Any information would be greatly appreciated. Thanks.
>
>Roger Peffer- rpeffer at ctc.edu

Roger, what kind of evidence do you have for this? Photos? Measurements?
Hopefully both? I'd be very interested in learning more about this. The
only hybrids mentioned for this family in the primary reference on North
American bird hybrids (Cockrum, E. L. 1952. A check-list and bibliography
of hybrid birds in North America north of Mexico. Wilson Bull. 64:
140-159) are between Common and Hoary redpolls, Common Redpoll and Pine
Siskin, and Pine Grosbeak and Purple Finch (!!!!). A Red Crossbill x Pine
Siskin hybrid was collected in North Dakota and reported by Dan Tallman
some years ago. There may well be others in Eurasia. No Purple X
Cassin's, which presumably would be somewhat difficult to detect, and it
will be exciting if you can document such birds. Do you capture them
regularly enough so that someone might be able to take a blood sample?

Tom Hahn, a friend of mine, is writing the Birds of North America account
on the Cassin's Finch, and I imagine he'd be interested too.

Dennis Paulson 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