[texbirds] Blue Jay migration - old data
- From: Chuck Sexton <GCWarbler@xxxxxxxxxxxxx>
- To: TexBirds Posting <texbirds@xxxxxxxxxxxxx>
- Date: Fri, 7 Sep 2012 08:23:09 -0500
TexBirders--
Joe Kennedy's remark that it is hard to discern Blue Jay migration in
an area like urban Houston reminded me of some research I had done
back in the mid-1980s: I compiled selected CBC data in the area
along the I-35 corridor (Waco, Austin, San Antonio) which was--at
that time--in the general vicinity of the western edge of the Blue
Jay's "natural range" in upland and riparian woodlands. This was in
conjunction with my graduate studies of the impacts of urbanization
on bird populations. If I recall correctly, I went back about 20 or
25 years (the period of record for useful CBC data) to see if I could
see trends of several urban-adapted or urban-adapting species. One
of the interesting tidbits that I noted was a fairly regular cycle of
Blue Jay influxes about every 4 to 6 years in that particular
region. I took those spikes to be the periodic immigration of
migrant Northern Blue Jays.
That tangent to my other graduate research never got published but
perhaps it's time to dust off that data, update it, and see (a) if
those trends have continued, and (b) if they might be of any utility
for gaging WNV impacts. I'll let you know when/if I can find that
old cardboard box with era graduate era data in it.
Chuck Sexton
Austin, TX
Edit your Freelists account settings for TEXBIRDS at
//www.freelists.org/list/texbirds
Reposting of traffic from TEXBIRDS is prohibited without seeking permission
from the List Owner
Other related posts:
