Can somebody please explain this bird to me? At our place in the Methow Valley I saw two magpies together; one was normal, the other, not. This latter bird had a completely white throat, breast, and belly, with no trace of black (on its underparts) anywhere below its bill, where there should have been the black bib. Also, this bird was noticeably smaller (by at least several inches) than the other. What's with this bird?

Thanks.

Birch Berman
birchb at methownet.com