I don't have specific sources, but it seems to me the (English and
American) ornithological community has worked to standardize all common
names for the birds of the world. Hence the recent _official_ changes of
Black-shouldered Kite back to White-tailed Kite and the Marsh Hawk to
Northern Harrier (so as not to be confused with old world species) etc.
This being true, perhaps the capitalization is used to connote that the
name is an "official" one. This way we know were all talking about the
same thing. Basically its just a way to get around the more Aukward
Latin names, so maybe it is redundant. Since most of us use these
English names regularly (as opposed to the Latin names), having a
standard is important to facilitate common understanding. Writing bird
names in capitals acknowledges that we are employing this standard in our
discussion so that there will be less confusion. Otherwise, you might
say buzzard, and I might say Turkey Vulture even though we are talking
about the same big black bird.
The standardization of these English names
seems to have worked. We (the people I bird with) make efforts to adopt
the new (AOU) name changes as they occur as do all the bird books. There
doesn't seem to be any inconsistencies between different books written at
similar times any more with regards to these name changes. On the other
hand, other groups of organisms do not seem to have standardized English
names. Is it a Chicory or a Douglas' squirrel? Is it Indian plum or
ouzo berry (I may have spelled these wrong)?

Personally, I like the capitals. If anything it makes skimming
the bird-e-mail easier! But really, it anthropomorphizes the birds to
the extent that it seems to bestow upon them validity in their own
right. By capitalizing the name of the animal it serves to elevate the
organism beyond something we possess to something that we must
respect. I am usually against anthropomorphism when dealing with
science, but in this case I'll make an exception. Heck, the birds
deserve our respect. In a way it fictionally gives voice to the subject
(the bird) as if it is saying "hey, I am a life form like you, at least
acknowledge
that before you proceed." (Have I made you all sick yet?) I think we
could all use that little reminder now and then and I am glad that we
have built it into our written word (knowingly or not). Acknowledging that
may help us to be more efficient and ethical (according to our own
personal ethical systems--I am NOT pointing any fingers here) in our
experimentation, observation
and data collecting. (Do I really need to get closer to that bird for a
better photo? As long as we're going to capture all these birds to
band is there any extra data we can collect along with wing and tail
measurements that may reduce the number of birds we have to harass
for a future study?)
So mark me down in favor of capitalizing bird names. (I should
mention that I did get points off for writing in this way on a school
paper once (ignorant non-bird people!).)

--
David Bailey, psu03321 at odin.cc.pdx.edu