>At 09:50 AM 8/14/99 -0700, Rob Saecker wrote:
>>Tweets,
>>
>>a couple of weeks ago, I heard the leader to a piece on NPR, the gist of
>>which was that birds are good indicators of global warming; i.e., as the
>>climate warms, birds will find suitable habitat in more northerly areas
>>that would previously have been inhospitable. This may help explain the
>>northward range expansion of scrub jays and grackles, for instance, and
>>maybe such oddities as little blue herons in the Bay Area, or summer
>>tanagers in Sacramento. I didn't, unfortunately, hear the whole piece,
>>which typically would have included someone with an opposing or alternate
>>viewpoint. Anyone have any critiques of this theory? Know of any published
>>references on this topic? Thanks...
>
>I know there's been some published work on the average departure
>and arrival time of raptors in eastern Canada over the past
>two ?I think? decades.
>
>The gist of it is that they've been arriving and nesting earlier,
>and it's statistically significant (obviously, there's annual
>variation which must be taken into consideration).

>Such correlations might be related to global warming, might be
>due to other causes, but as more and more of them are discovered
>and as work is done which ties down causes when possible, I'd
>be very, very surprised if the case for global warming were in
>any way weakened...- Don Baccus, Portland OR

I've also read an article (Birder's World, maybe, but don't quote me)
that American Robins are arriving earlier and earlier in spring
(in the Eastern parts of their range, not the PNW of course). Since their
arrival seems to be dependent on when the ground thaws, it is also
possibly related to global warming.

John Chapman
Seattle