Subject: Birds and global warming
Date: Aug 14 10:54:42 1999
From: Don Baccus - dhogaza at pacifier.com


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. I've not read the paper(s) myself, have just
seen references...

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 <dhogaza at pacifier.com>
Nature photos, on-line guides, Pacific Northwest
Rare Bird Alert Service and other goodies at
http://donb.photo.net.