Don, in all ornithological journals in English (not so in some other
languages), species common names must be capitalized. It seems to me that
this holds in most birding magazines, too. In newspapers and some other
magazines (Time, for example), bird common names aren't capitalized.
Capitalization is not the rule for other taxonomic groups, and the bizarre
consequence of this is that you'll see a report or paper in which "the
tigers chased the Ostrich through the western hemlock forest" (or something
like that).

There was a note in Birding several years ago that bird common names had
become proper names from usage (and "official" status) and that it was
therefore correct to capitalize them.

I don't have a strong opinion on this, but in a way it does make sense to
capitalize these names so they can be recognized as a "proper name" for a
species. Thus a sentence such as "the little gulls were determined to be
Little Gulls" would make perfect sense. I wouldn't object to "official"
English names of all groups being capitalized.

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