Subject: migrants [re Neil Fergusson]
Date: Mar 31 11:03:30 1995
From: sherman jarred suter - sut9 at midway.uchicago.edu


NJF: "It would seem that birds in the northern part of the breeding range
winter in the northern part of the wintering range, and a similar
case for southern birds."

>From its foggy depths my memory insists this is probably NOT the case -
rather for several N temperate migrants the more common pattern is that
birds from the more Nly part of the wintering range migrate to the
more Sly part of the breeding range. And the N part of the breeding
range is later filled by birds that have come farther. Can not recall
any citations to back this up (or even where or when I acquired the idea).
But is would make evolutionary sense: weather patterns would make the
more Sly breeding sites "safer" for occupation at earlier dates, and why
migrate any farther than one "has" to?
Sherman Suter
echino at uchicago.edu
but really at Paleobiology NHB-121 Smithsonian Institution W DC 20560