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Anti-Brown-headed Cowbird essay --long



Invasive Species, Wildlife management, Cause and Affect
What do cowbirds, House Finches, starlings, House Sparrows, feral Goats in
the Galapagos, camels in the Australian Outback, Cane Toads outside of the
Americas have in common? Of course you know, because you are birders..

All are the result of actions by individuals and organizations (often
deliberate) that have resulted in unforeseen and sometimes dire
consequences to ecosystems.
Does the state of Michigan maintain gamelands?  Do they manage areas for
the hunting of quail, dove, deer?  Do they mow and cultivate as we do in
many eastern states, --plant corn, rows of Russian and Autumn Olive as we
see near Brickhouse Rd.?  There are corn and grass patches planted
throughout the Long-leaf Pines in the NC Sandhills?and almost everywhere
that there are Wildlife Management dollars spent for game species?

If so, then Michigan, like NC, and most every eastern US state Wildlife
agency, is managing the habitat in a way that promotes the success of the
Brown-headed Cowbird. The Brown-headed Cowbirds (or more accurately land
use practices that favor their success), is one of the greatest threats to
our breeding passerines.

The once vast eastern forest of North America is now fragmented suburban
forest. The piedmont is a showcase fragmented (Cowbird) habitat. Some of us
write on this list of removing exotic or invasive plants. Performing such
services, doing something to help the environment is a rewarding and
altruistic act to be applauded.  Should such be restricted just to plants?
Many would say no, although it is perhaps not for the squeamish. When
marveling at a Scarlet Tanager?s brilliance, when one is mystified and
soothed by the soliloquy of the Hermit and the Wood Thrushes, one should
understand that these jewels to eye and ear are in jeopardy.

Cowbirds in bluebird boxes is not the true issue to those aware of another
picture.  We make judgement calls and decisions in all we do, and
government agencies sometimes make these on our behalf --sometimes with the
aid of biologists.  Brown-headed Cowbirds and their parasitic biology have
found impressive success. They now parasitize nests in remote vestiges of
eastern forests like the Monongahela in West Virginia, and the Great Smoky
Mountains. Species such as the wood warblers have been steadily declining,
and things like, deforestation, fragmentation, increased nest predators,
and the Brown-headed Cowbird are at the core of the discussion.

The gurgling song is beautiful, though when recording them, there is the
pervasive feeling that it is not a parabolic reflecting microphone that
should be pointed at them. Many exotics (and the Brown-headed Cowbird is
not), often start out innocently enough. Some are set loose (introduced)
with a purpose backed by sound biological reasoning. As with the Cane Toad
(Bufo marinus), in Australia, hindsight is 20-20.  The goal in wildlife
management, is to intelligently manage the habitat to produce the intended
balance or effect. If we want quail and dove, we should know that it will
also favor cowbirds. Maybe we could introduce a parasite that "only"
impacts the nest parasite, some cowbird specific pathogen, or a predator
that eats "only" Brown-headed (cowbirds?beyond the nestbox). Maybe what we
need is a bigger say in what we are managing for. 2 cents and then some.

Dave Ross,
Durham.