On Mon, 28 Oct 1996, Irene Wanner <iwanner at u.washington.edu> wrote:
>Where do these guys go for the winter, please? - Irene

Longish response to a short question:
When I lived in the Canal Zone, an ornithologist at the Smithsonian
Tropical Research Station discussed the migration of Turkey Vultures,
saying that the many thousands passing south each Fall/north each
Spring were U.S. birds, that they'd overflown all of Central America
in the fasting state, and that the majority wintered on playa lakes in
Venezuela. These lakes were said to dry up almost completely during
the winter, thus providing large quantities of dead flesh for the
visiting TV's. In discussing this species, Wetmore stated: "There is
no pause for feeding in these migrations,....", and also described
some differences in the color of the head skin between migratory birds
and those native to Panama. I do not know whether birds from the PNW
are included among those migrating throught Panama.
End of longish answer to a short question.

Addendum:
Which brings this to mind: a recent thread on BIRDCHAT discussed
mechanisms of speciation, during which the question was raised whether
the sedentary population of Sandhill Cranes in the Southeast
(principally in Florida) should be considered to be a separate species
from the migratory population wintering in California (and other
western States). In the same light, although the geographic separation
is certainly less-well defined, might the migratory TV's be a species
different from the sedentary Central American birds? I have no idea of
the answer, nor by what criteria this question might be satisfactorily
resolved. Nevertheless, perhaps some interesting food for thought.

Thanks!
a Buaidh! FX
F. X. Schloeder
Bellaire, TX
fx at sprynet.com