Avian Pox--A Moral Dilemma


Richard Beban <beban@...>
 

I've recently (last three weeks) begun feeding the wild birds in my
neighborhood, via two methods. I have a tube feeder that I hang outside
the bedroom window and fill with black oil sunflower seed; and I
scattered mixed birdseed on the neighbor's flat roof just below my
window.

Crowds of finches and sparrows come to the feeder; finches, sparrows,
three kinds of doves, and the occasional jays come to the roof. Not to
mention a one-day stand by an escaped black-masked lovebird.

I have just noticed in the last few days that many of the finches (at
least six of the regulars, who probably number 80-100) have avian pox,
small tumors in non-feathered areas. Some are missing feet as a result,
some are blind in one eye. The illness seems to be mostly among the
females, and in a few newly fledged. None of the other species seem
affected.

A search on the 'Net revealed one source that suggested I immediately
remove the feeder, wash it with a 10% bleach solution in soapy water
(which I do every three days anyway) and then LEAVE IT DOWN FOR TWO
WEEKS, to discourage the spread of the disease and scatter the present
population of infected birds.

I have trouble with this advice, since my intention is to feed the
birds.

If it's the only way to diminish the disease, I will do it, but I wanted
to ask other opinions of people more expert than I.

Second question: Since the seed on the roof is more widely scattered,
and the finches congregate, but they aren't as crowded as at the feeder,
should I stop doing that, too? (I don't wash the neighbor's roof with a
bleach solution.)

Thanks in advance for your advice and opinions.

Richard Beban


Stephen J. Davies <sdavies@...>
 

Certainly sounds like avipoxvirus infection (the skin lesions are most
likely the result of infection with this virus). It is quite persistent -
hangs around in the environment for a while. Cleaning the feeders is
definitely a good idea. The virus can be transmitted directly from bird to
bird so, unfortunately, it is probably a good idea to stop feeding - both at
the feeders and on the roof - attracting numbers of birds to one area
increases the likelihood of transmission. Young birds, and those subject to
other stresses, such as moulting, are most susceptible to infection - hence
there are a lot of susceptible birds around at this time of year. The
majority of infected birds are probably young birds (of both sexes) in
female-like plumage (not just females per se). There is no good treatment
(this is a virus infection), and mortality rates can be high. Depending on
the subtype of virus, it may spread among different species, or be
restricted to one or more closely related species.
IMHO, definitely stop the feeding.
Stephen

Stephen J. Davies BVSc PhD
Tropical Disease Research Unit
Department of Pathology
University of California San Francisco
VAMC 113B
4150 Clement Street
San Francisco, CA 94121

Tel: (415) 476-1659
Fax: (415) 750-6947
Email: sdavies@socrates.ucsf.edu


Alan Hopkins <ash@...>
 

Dear Richard Beban,

Thank you for being a responsible bird feeder. Unfortunately, from my
experience I think most people are not concerned with the health of the
birds visiting their feeders. I have seen many feces encrusted feeders
in the homes of committed birders and environmentalists. I am on the
radical side of this issue and would prefer that people either feed
birds in a very limited way, or not feed bird at all. The birds who
benefit most from feeding are those who don't need our help. I have just
come back from Joshua Tree Monument where they have signs that read
something like: Keep Wildlife Wild � don't feed the animals.

Here is a letter I wrote to Audubon magazine in regards to two stories
they ran in the July/August issue:


�Dear Editor,


I read with great interest the stories �The Audubon Garden Makeover� and
�Bye-Bye Blackbirds� � the story about poisoning millions of blackbirds
in to protect Sunflower crops in South Dakota. It seems that a wildlife
garden is incomplete with out bird feeders, lots of bird feeders. But I
can�t help but wonder if Red-winged and Yellow-headed Blackbirds are
being killed in the Dakotas so we can feed House Finches sunflower seeds
at home? And what about all that millet? How many wetlands are filled,
and how much land is plowed under, and then sprayed with herbicides and
pesticides, so we can enjoy the clamor of birds at our feeders?

Stephen Kress implies in �The Winter Banquet� [Audubon January-
February 2000] that dispensing one billion pounds of bird seed annually
in the U.S. has no impact on the environment. How can this be? Would we
be so accepting of people who randomly dispersed a billion pounds of
fertilizer onto native plants? Dr. Kress outstanding work to restore
seabird colonies provides a perfect example of the imbalance that can
occur when one species is subsidized at the expense of others. If
feeding birds had no impact, the Puffins Murres, and Rosette Terns he is
trying save would not be effected by the Herring Gulls who benefit by
subsidized feeding at east-coast dumps � but this is clearly not the
case. Will the Cowbirds that visit your feeder during the winter, lay
their eggs in a Kirtland�s Warbler�s nest in the Spring?

What has happened to our notion of ecology? Where is the balance in a
garden full of birds that are only there for an unlimited source of the
bird food equivalent of a Big Mac? A true wildlife gardener should be
looking for quality and not cacophony in the garden.

I would like to make a suggestion to those people who want to have a
deeper experience in the garden. Take some of those sunflower seeds from
your feeder and propagate them. Take a walk in a local natural area,
note what plants the birds are using, and plant those plants. Eventually
you will be able to throw away the bird feeders. Donate the money you�ve
saved on bird seed to prairie, wetland, and riparian restoration. In
this way you will truly be helping the environment and fewer blackbirds
will have to die.�

Richard, I don't know what your situation is, sounds like you don't have
a garden. You could put up a hummingbird feeder (I have fewer problems
with these, as long as they are kept clean). One thing all birds need is
a source of fresh clean water.

Alan Hopkins