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Re: Cowbirds and such



Cowbird fanciers,

Dr. Mueller and Alex's comments are intriguing. My 2 cents: there is
evidence in Southeastern Native American
traditions and in other evidence that Bison and Elk were once native to the
Carolinas. The "unbroken forest" notion is probably largely a myth, as
natural fire and agricultural practices had broken and opened the forest in
the Stone Age. Therefore, Cowbirds in the Carolinas may be returning to an
older niche, merely a long-term range fluctuation.

Steve Compton
<scompton@sc.rr.com>
----- Original Message -----
From: "Helmut Mueller" <hmuelle@earthlink.net>
To: "Alex Netherton" <alexnetherton@charter.net>; "Carolina Birds"
<carolinabirds@duke.edu>
Sent: Friday, May 09, 2003 10:40 AM
Subject: Re: Cowbirds and such


> There is one problem with the following bison herds explanation. There are
> other species of parasitic cowbirds living outside of the range of bison.
> In Argentina there is a species of cowbird which lays its eggs only in the
> nest of another, non-parasitic species of cowbird. This is thought to be a
> "primitive" species from which the habit of laying eggs in a variety of
> species evolved. Many species lay eggs in the nests of other individuals
of
> their species. There are many other species of brood parasites, of which
the
> European Cuckoo is the best known example..hence the word "cuckolded"
> There is little question that Brown-headed Cowbirds have become much more
> abundant in the east, that they like short grass & the company of large
> grazing animals. Harold Mayfield has speculated that the recent in
expansion
> in range & abundance of cowbirds is because of the increase in lawns, golf
> courses & c, allowing for good habitat for cowbirds in close proximity to
> the nests of woodland species that formerly had very limited, or no
exposure
> to cowbird depredation.
>
> -- Helmut C. Mueller  Ph.D
>
>  Professor Emeritus
>  Dept. of Biology & Curriculum in Ecology
>  University of North Carolina
>  Coker Hall CB# 3280
>  Chapel Hill, NC 27599-3280
>  Phone: 919-942-4937
>
>  Permanent email address: hmueller@email.unc.edu
>
>
>
>
> > From: Alex Netherton <alexnetherton@charter.net>
> > Date: Thu, 08 May 2003 23:41:57 -0400
> > To: Carolina Birds <carolinabirds@duke.edu>
> > Subject: Cowbirds and such
> >
> > Hi folks. I have been amused by the "smoke" war (no flames yet) about
> > Cowbirds; I daresay I might remove a cowbird egg from a Bluebird nest,
> > maybe even a nestling. Some might remember the story of "The Last
> > Bluebird", which died in our clothesline post over 40 years ago and I
> > did not see it, and thought I would never in this life see one. A pair
> > is again nesting in a box in our front yard. There has also been a
> > female Cowbird hanging around. Maybe ought to go check on something,
> > just to make sure... Hmmmmm.
> > Cowbirds are thought to have evolved in the Great Plains, following the
> > great Buffalo herds, their main source of food, or rather, source of
> > scaring up their food. With this mobile food source, it makes sense that
> > any female that might have had a tendency to "dump" her eggs in a
> > nother's nest would have left far more of her genes, and the tendency to
> > "dump" along with them.
> > There are other nest parasites in the Eastern US, but I don't think any
> > are "obligate", that is, having to do it. (Cowbirds have no ability to
> > make a nest or care for young.)
> > With the breaking up of the Eastern forest, the turning of much of the
> > land int pasture, they spread into this "new" habitat, and into bird
> > populations which had no resistance to them.
> > Shame; they are right interesting, but I don't think I want one in my
> > front yard...
> > Trees are full of warblers here, but darn if I can ID any of them.
> >
> > --
> > Alex Netherton
> > The Appalachian Naturalist
> > Asheville, NC
> > alex@alexnetherton.com
> > http://alexnetherton.com
> >
> >
> >
>