[CT Birds] "countability" of Trumpeter Swans
mantlik at sbcglobal.net
Mon Mar 29 20:32:02 EDT 2010
In fact, the Swans are adults, as aged but the all-black bills. Immatures would still be exhibiting some pinkish color on the middle part of the bill. I suspect the dirty gray necks are a result of feeding in that pond or at other locations.
I intend to do some research on where these birds might have come from, but it's a good chance we'll never know for sure.
As Nick's ABA link stated, it's a rule of thumb that a breeding population has to be viable and sustained for at least 15 years. (By the way that's how the CT ARCC also determined when to add Monk Parakeets to the official state list).
From: "Mntncougar at aol.com" <Mntncougar at aol.com>
To: ctbirds at lists.ctbirding.org
Sent: Mon, March 29, 2010 8:21:14 PM
Subject: Re: [CT Birds] "countability" of Trumpeter Swans
I don't know much about TRSW, having seen only 1 (in Ohio - and I counted
it!), but those birds look to me like they are juveniles or very young, as
they clearly appear to have gray necks and heads. I'm sure someone will
quickly correct that if I'm wrong. However, if that's right, the fact that
they have no bands or markers makes me think they were hatched and fledged
in the wild. That leads to the question of how long the birds have to be
in the wild (generations) before they can be considered wild (and
countable). Any answers or opinions?
This list is provided by the Connecticut Ornithological Association (COA) for the discussion of birds and birding in Connecticut.
For subscription information visit http://lists.ctbirding.org/mailman/listinfo/ctbirds_lists.ctbirding.org
More information about the CTBirds