Ileen Weber wrote:

>One stop on the Kirkland's Warbler Tour in Mio, Michigan was a visit to a
>cowbird trap that has been successfully used to control brood parasitism
>on the Kirkland's Warbler.

(snip)

>This has apparently been a very effective cowbird control and is copied
>in other places now.

One more thing that could be said about this is that it's only being done
where brood parasitism is thought to be having an effect on some
endangered/threatened species (the system doesn't have financial/staff
resources to do it anywhere else). The only places I know about are in
Michigan for Kirtland's Warblers and in Texas and Oklahoma for Black-capped
Vireos. Several of the museums in this area have received bags of frozen
cowbirds from the Black-capped Vireo area and prepared them as specimens.

If we could just convince cowbirds to parasitize starlings and house
sparrows (they would first need to evolve a protrusible cloaca, which
allows female cuckoos to parasitize hole-nesters)!

Dennis Paulson, Director phone 253-756-3798
Slater Museum of Natural History fax 253-756-3352
University of Puget Sound e-mail dpaulson at ups.edu
Tacoma, WA 98416
http://www.ups.edu/biology/museum/museum.html