FreeLists / birdky / [birdky] Re: FYI: Discussion of origin of orioles (long)

["Mark Monroe" <markmonroe1@xxxxxxxxx>]

(Apologies for the long response, but this topic really had me thinking.)


The discussion of origin is always important when it comes to out of range
or out of season birds (more so with non-passerines).  Those that know me
know that I tend to be conservative on most of these things.

Having said that, I find the arguments that I read far from convincing...or
even motivating.  Choosing these three, and only these three orioles in the
east (when others are present as we speak) is of course going to make
someone think something is odd.  But if you look at the big picture east of
the Mississippi, there are quite a few orioles present (mostly Baltimores
and Bullock's).  If you expand the time frame to the past few winters, there
are even more and it is a notable trend.  As someone in the Indiana thread
pointed out, there are quite a few precedent sightings of Scott's and
Bullock's Oriole in the eastern US in the last 10-15 years in January,
February, and March, so that in and of itself is nothing astounding,
particularly considering recent climate trends.  There are other groups of
birds showing similar new and unusual northern winter trends also.  Perhaps
not the best example, but the one I'm most familiar with and that helps
illustrate a point, is Rufous Hummingbirds.  For the record, Brainard and I
have banded 6 and only 6 of these in the region this year, and they were all
within 60 miles or so of each other (even though we handle Southern Indiana
and all of Kentucky).  This does NOT put their origin in question though, as
it is nothing more than coincidental.  Such is the nature of birding.

Now, one of the arguments was that the Audubon's in southern Indiana has a
possible foot ailment common with captive birds.  Fair enough.  This is also
the most aberrant of the 3 orioles in question and perhaps that bird should
be scrutinized closer.  However, it is interesting to note that none of the
three has a band, something that virtually any and all legal captive birds
would have.  The only piece of evidence other than proximity to the
Audubon's given for the illegitimacy of the Scott's Oriole that I saw was
wear on the tail feathers caused by being caged, particularly the outer
right tail feather.  Again, I find this far from convincing.  As a bander
having handled hundreds and hundreds of birds, I can tell you there's
nothing about the wear pattern on the Scott's that jumps out as odd to me.
I have little doubt this bird hunkers down somewhere tight on these cold
nights, a factor that could easily cause wear on the tail.  For the record,
in Peter Pyle's comments posted by David, the tail feathers on that bird may
or may not have been replaced, meaning as a young bird they could
potentially be up to ~9-10 months old.  Furthermore, being a young bird, its
status as a captive is far less likely.  The chain of events that would
cause this bird to 1) be captured as a young bird yet 2) be able to survive
fine in the wild in winter in Kentucky, 3) kept with multiple species of the
same genus, 4) brought out of range to our area (most likely illegally), 5)
escaped (along with the others), 6) all show up relatively healthy at
feeders where they are reported, and 7) without any real piece of credible
evidence to show this was the case (such as bands)....well it simply strains
credibility.  I still am trying to fathom WHO, other than possibly a zoo,
would ever have a young female Scott's Oriole in captivity. It's not exactly
the most brilliantly plumaged bird in the world or a species commonly kept.

A far more logical answer is that these individuals are part of the larger
and more obvious trend of birds (including orioles) showing up in winter in
the Eastern US, most likely due to global warming.

Mark Monroe
Louisville


On 2/13/07, Palmer-Ball, Brainard (EPPC OOS KNPC) <
Brainard.Palmer-Ball@xxxxxx> wrote:
>  Some of you may be interested in reading some discussion now occurring on
> the Indiana listserve dealing with the origin of not only our Scott's Oriole
> and the Indiana Bullock's Oriole, but a recently discovered female Audubon's
> Oriole in the same general vicinity as the other two in southern Indiana!
> One has to wonder ... !
>
> http://birdingonthe.net/mailinglists/INDB.html#1171379957
>
> bpb, Frankfort