[rec.birds] measuring migrant popultation

geek@mit-amt.MEDIA.MIT.EDU (Chris Schmandt) (01/17/90)

An interesting article in Monday's Boston Globe.  Seems an ornithologist
named Sidney Gauthreaux had been studying recent decreases in the
number of Gulf Coast migrants.  He wanted to quantify this, and hit
upon the idea of using archived NOAA weather radar data.  It seems
that big flocks of migrants appear quite distinctly on weather radar.
And the weather radar stations archive photos of the screens every
20 minutes for something like the past 20 years.

Anyway, the preliminary findings indicate a loss of perhaps half the
popluation over 2 decades, which is apparently much more significant
that the decrease revealed so far by the North American Breeding
Bird Survey.

This data is only preliminary, and indeed he's looking for funding
for more thorough study of the weather radar information.  But it's
a pretty shocking loss (due to loss of rain forest habitat, of course,
is the common belief).  I thought these results were pretty dramatic,
and the methodology interesting enough to post about it.  Perhaps
someone has read the original paper?  (supposedly at a "symposium
on migratory birds last week at Woods Hole").

chris