Date: 6/20/19 8:04 pm
From: Tim Rodenkirk <timrodenkirk...>
Subject: [obol] So You Think You have Seen Allen's Hummer in OR?
Hi All,

Thought it was high time to have a discussion about Allen's Hummer in OR.
Recent research (Research - Brian Myershttps://bmyers.info/research
<https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&cad=rja&uact=8&ved=2ahUKEwiQz8WkxPniAhVMJKwKHfx7AS0QFjADegQIAhAB&url=https%3A%2F%2Fbmyers.info%2Fresearch&usg=AOvVaw1pLS82FI_2ibtegzbqRslu>)
on the south coast and into CA finds that the hybrid zone for
Rufous/Allen's Hummers runs from Florence, OR to Arcata, CA- Wow! I don't
have any more in depth info on the study but I bet he would be interested
in getting e-mails on his study- I know he mist-netted and collected many
birds as well as collected DNA info on birds he did not actually collect.
Further the research talks about how the display dive given by the hybrids
is variable. The study "found" (certain south coast birders have known for
many years) that the center of the hybrid zone is from Bandon to Port
Orford. Arch McCallum also did some recording work and found hybrids in the
Bandon to Port Orford area before this research.

I did point counts at New River, Coos which is within the center of the
hybrid zone. This was from 1996 through 2010. During this time I literally
saw hundreds of male Selasphorus (Rufous/Allen's). In order to ID them
better, after surveys, I set up a spotting scope. Once you figure out a
breeding male's perches, it is relatively easy to get a scope on them so
you can see back color. This is something I think most birders would never
do since it takes some time before you can figure out perches and actually
see the birds, with their backs facing you, on the perch. In 90+% of the
time the birds doing Allen's type displays only had partially green-backs
which confused me since the field guides show a completely green-back for
male Allen's.

What the research shows and what I noted was although you may see a male
Selasphorus doing an Allen's type display, it could still be a hybrid.
That means that in addition to seeing the display you need to get really
good looks at its back to decide if it is a hybrid or not (totally
green-backed or only partially green-backed, see field guides).

In recent years I think Coos birders have become more wary of this and thus
the Rufous/Allen's filter on eBird. I now think this filter should be
extended to Curry and, well, all of Oregon. I speculate (!) that when
birders go down to Brookings and see an Allen's type display from a male
Selasphorus they say ka-ching, got my yearly Allen's. I think we need more
close scrutiny of these purported Allen's Hummers in southern Curry- are
they really "pure" Allen's- maybe some, but are there many hybrids- does
anybody really look closely at what percent of the back is green or even
know that partially green-backed birds are likely hybrids?

As for females, say you have a feeder in Brookings with an obvious male
Allen's with a female, how would you be able to tell if the female was an
Allen's, Rufous, or hybrid if separating male and female Rufous/Allen's is
mostly impossible without great tail photos or a bird in hand? In other
words, how can you safely say that any female or young birds are Rufous or
Allen's in Coos and Curry? I had a male Rufous/Allen's in my yard the last
three years (not this year). It did a mostly Allen's type display the first
year and I was convinced that was what it was; however, when likely the
same bird came back the second and third year it would alternate Allen's
and Rufous displays and well it was maybe 75% green-backed- ugh! I see that
Allen's Hummers are routinely reported in southern Curry on eBird, sometime
in number with no notes, this really bothers me. Obviously birders assuming
that Selasphorus are Allen's because, well, that's what we have in Curry
right? Maybe they saw a male display, but did they check the color on the
back- I bet rarely.

I forgot to mention that at New River I saw completely red-backed Rufous
looking birds doing Allen's displays. I have seen the same at the base of
Mt. Bolivar (3,000' elevation) in SE Coos.

So, what I am hoping to convince Russ Namitz of, our South Coast eBirder
reviewer (with way to much input from me, a non-eBirder but maybe someday),
is to put a year round filter on Allen's on the south coast. In addition,
I have read from researchers, that in the old field guides that said 5% of
Rufous could have some green on their back, that these are just likely
hybrids. Such confusion! Anyhow, I think any purported Allen's Hummer
would have to be a male and would need supporting observations to be
accepted on eBird. I know, this is a total paradigm shift for many long
time OR birders, but your lifer Allen's just may have been a hybrid!

In my opinion this may end up meaning that if Joe Jones in Brookings has a
"good" Allen's at his feeder, birders, who want to get an Allen's and not a
hybrid for their year or life list, will go to his feeder. Pure Allen's in
OR could be a pretty tough bird? I have seen them in Coos but I have
looked at hundreds if not thousands of males through spotting scopes on
their perches and watched their dives, something future birders probably
should be doing to find a "pure" Allen's (if not just camping out at a
feeder where a male is known to be).

I hope we can find out more about the hybrid zone in Curry- careful
observation of males by OR birders in the next decade could really
enlighten us to what is going on with these species in Curry County.

Expecting some feedback...
Tim Rodenkirk
Coos Bay

 
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