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A note from Bob Sargent (fwd)
- To: carolinabirds@duke.edu
- Subject: A note from Bob Sargent (fwd)
- From: Joshua Stuart Rose <jsr6@duke.edu>
- Date: Thu, 18 Nov 1999 11:57:35 -0500 (EST)
- Sender: carolinabirds-owner@acpub.duke.edu
Hi C-birders,
Bob sent this to the Virginia birding listserv (which is now being
archived on Jack Siler's website, if anyone is interested). However,
given the level of interest in wintering hummingbirds around here, I
think many Carolinabirders will enjoy reading it as well.
Just to provide context, the discussion leading up to Bob's note was on
the value, or lack thereof, of banding hummingbirds in winter in this
region: whether any of them survive, and whether banding might decrease
their chances of survival. Read on...
Joshua S. Rose
Duke University
Department of Zoology
jsr6@acpub.duke.edu
http://www.duke.edu/~jsr6/
-------------------Forwarded Message-------------------------------
Virginia Birders and anyone interested:
I'm Bob Sargent, President of The Hummer/Bird Study Group, Inc. I am a
Master Bird Bander who specializes in the study and banding of
hummingbirds. I've been asked to comment on the recent and future banding
of hummingbirds in your beautiful state. I recently assisted in the
writing of an article for Virginia Wildlife suggesting that hummingbird
lovers in Virginia leave a feeder up in winter to assist in the study of
wintering hummingbird species. I should note up front that these feeders
in winter did not attract wintering hummingbird species to Virginia. It
is not possible that a hummingbird in the Northwestern US would know in
advance that someone in Vienna, Virginia would have a feeder waiting for
them when they arrived for their winter visit.
Hummingbirds have likely wintered in the Eastern US for untold
generations; that includes Virginia! It is the discovery process that has
made them visible at last. As a hummingbird bander I have have banded
many thousands of hummingbirds in my home state of Alabama. In addition
to the huge numbers of Ruby-throated, I have also banded and documented
nearly one thousand wintering hummingbirds representing eleven (11)
species in surrounding states. The largest number by far have been Rufous
Hummingbirds. Most of the hummers that will soon be detected in Virginia
will be Rufous.
Rufous hummingbirds are a vigorous and cold hearty species. They nest
from Northern California northward to as far away as Southeastern Alaska.
Male Rufous are defending territories and females are incubating eggs
when temperatures can easily be below freezing at night. They are skilled
in the use of torpor as a defense against the rigors of cold. I have
banded dozens when temperatures were in the zero to ten degree F range (0
to 10 F). When temperatures are freezing and above, their daytime
activities are simply a matter of routine. Most of these wintering Rufous
not only survive these temperature extremes, but regularly return to the
same wintering sites year after year. Rufous hummingbirds can easily
survive without floral nectar. They are however opportunist, and will
exploit hummingbird feeders if they are available. Normally they would
get most of their "wild nectar" in winter from the weeping wells opened
by Yellow-bellied Sapsuckers. It is my opinion that the main food
consumed by hummingbirds in winter is arthropods, tiny insects. It is
quite possible that we should consider hummingbirds as tiny flycatchers;
masters at gleaning insects and eggs from evergreens and conifers and
flycatching them on the wing.
Migration for these wintering Rufous appears to be along a series of
wintering sites. Those that occur in the northern parts of the eastern US
are likely to leave those areas and drift southward as winter deepens.
All will not do so. A few will attempt to spend the winter and most will
succeed. As with bird species of all kinds, severe winters (several days
with constant below freezing temperatures) will kill some individuals, be
they sparrows, juncos, goldfinches or others. It is the way of survival
of wild creatures. The fact that cold weather will be lethal to some
birds is not a new occurrence. It is after all, the fittest in any
species that survive. It is the same with hummingbirds.
To those in the wildlife rehab community, I would urge caution if they
are involved in the routine capture and relocation of healthy birds of
any species; this includes hummingbirds. If wintering hummingbirds are
ill and cannot fly, then their assistance is indeed warranted. It should
not be, however, their routine practice to capture and attempt to
relocate or house healthy birds. As a long time adviser to the Alabama
Wildlife and Rescue Service, I have nothing but admiration for the time
and effort put forth by tireless volunteers.
The banding of birds, including hummingbirds, is part of a worldwide
effort to learn enough about birds to protect them for all time. In most
cases bird banding is done by individuals who receive no pay for their
long hours of hard work. Little is known about the lives of hummingbird
species. The recent discovery of wintering species in the Eastern US is a
prime example of how little is known. When birds are banded, we can then
study the natural history of individual species and even individual birds
within a species. Many of these banded winter hummingbirds will be
encountered and documented again and again. From these data collected, we
gain precious insights into their daily lives. Things such as their
migration routes, dates of their migration, their longevity and many bits
of data regarding their general physical condition in winter. Incidental
information concerning molt sequences and ageing and sexing techniques
can also be illuminated.
It is from many thousands of hours of experience that I ask for you
cooperation in this study. If as individuals, you have questions or
reservations about bird banding, please feel free to contact me. I will
attempt to answer any questions that you might have. If you need
references regarding the work of my organization, feel free to check
with any of the ornithological societies in the Eastern US. You may
contact the Bird Banding Laboratory in Laurel, Maryland for an official
assessment of our skills and experience. For additional information
regarding our organization and our work, you may write:
The Hummer/Bird Study Group, Inc. (non-profit)
PO Box 250
Clay, Alabama, 35048
Thank you for this opportunity to speak with you. Good luck and God
Bless.
Bob Sargent
7570 Mack Hicks Road
Trussville, Alabama, 35173
205-681-2888
205-681-1339 FAX
Rubythroat@AOL.COM