It was suggested to me that I should not rule out Black-chinned on nest
structure alone. Thus, I considered characteristics for Black-chinned
versus Anna's Hummingbird.
I believe the folded wing when the bird is perched feeding young (with its
back to the camera) appears to be a Calypte Hummingbird and not an
Archilochus hummingbird. Please see examples from
http://home.earthlink.net/~zoiseaux/ This site has some good photos and
references the Anna's Hummingbird as having a "saber" shaped wing (which is
consistent with the mystery photo when the bird is perched). The
Black-chinned has much thinner inner primaries than outer (although the
young birds appear to have such thinner inner primaries).
The bill appears long and curved. This is much more characteristic of
Black-chinned.
The birds wings appear to stop at the end of the tail (they do not appear to
end beyond the tail). Altough, this characteristic is difficult to see in
the photos and in one photo, I think the wings might end beyond the tail.
In Black-chinned, the wings extend well beyond the tail (this is a useful
characteristic to separate Black-chinned from Ruby-throated in eastern US)
and like previously stated, one in one photo the wings appear to extend
beyond the tail.
The mantle coloration in Black-chinned is a very dull green. At least in
the flying photo, the mantle appears very bright green. This favors Anna's
Hummmingbird.
The throat is very gray. Black-chinned females have a whiter throat.
Anna's should show some red flecking, although this can be missing in some
Anna's.
The area behind and below the eye is usually darker in Black-chinned than in
Anna's, almost masked. The photos here are more suggestive of
Black-chinned. There were some comments about a white spot beyind the eye
(or a white line behind the eye). This is very variable and not reliable
for either species.
Thus, I am not sure you can safely rule out Black-chinned.
Jim Holmes
Sacramento, CA USA
-----Original Message-----
From: James F. Holmes
Sent: Friday, June 15, 2007 7:43 PM
To: 'Reg Clark'; 'David Stowe'
Cc: 'birding aus'
Subject: American Hummingbird ID query
I took a quick look at the photos of the USA hummingbird that have recently
been circulated on this list. Although, I am no hummingbird expert, I do
live in california and regularly have Anna's at my feeder.
It was photographed on a nest (only the female), reportedly in California.
>From initial impression, it appears to be either an Archilochus or Calypte
hummingbird. The Selasphorous species (Allen's, Rufous, and Broad-tailed
are easily ruled out by the coloration (actually the lack of rufous
coloration). The large hummingbirds (Blue-throated and Magnificent) are
structurally and plumage much different than this bird. Ruby-throated
hummingbird (an Archilochus species) is ruled out by range (it has only been
recorded in California a few times and certainly has never nested).
This leaves, Black-chinned, Anna's, and Costa's Hummingbirds as possible
choices.
The structure of the nest immediately rules out Black-chinned Hummingbird
(which makes a very smooth nest without the lichen type objects). Thus,
Anna's and Costa's are left. These can be difficult to separate and voice is
best. Since this bird has obviously nested in a developed area, I would lean
to Anna's Hummingbird which is common in developed areas. Costa's is much
more of a desert species but I can't tell from the photo if this is a
California desert community.
Plumage characteristics are confusing in this bird.
Anna's has a long tail such that the wing tips fall short of the tail. At
least one photo suggests the wing tips extend to the tail but not beyond.
The photo of the bird in the nest suggest that the wing tips stop before the
tail. In Costa's Hummingbird, the tail is short such that the wing tips
extend beyond the tail. The photos would suggest Anna's based on this
characteristic.
The wing structure can aid in identification. In Anna's, the inner
primaries are the same width as the outer primaries. In Costa's, the inner
primaries are about half the width of the outer primaries. The photo of the
young birds clearly demonstrates that the outer primaries are much wider
that the inner primaries. Assuming that primary width of a juvenile Anna's
is the same as in adult, the primary photos strongly suggest Costa's. This
field mark has been questioned by some.
Anna's is a very gray hummingbird on the throat and chest. Costa's tends to
be much whiter (especially on the belly). Based on the grayish coloration
on the throat and chest, I would strongly expect Anna's.
I would guess Anna's Hummingbird. However, the clearest field mark is the
width of the primaries in the young birds which supports Costa's. It would
help if we knew where in California this was taken.
Jim Holmes
Sacrament, CA USA
-----Original Message-----
From:
On Behalf Of Reg Clark
Sent: Friday, June 15, 2007 6:35 PM
To: David Stowe
Cc: birding aus
Subject: American Hummingbird ID query
Hello David,
How about Anna's Hummingbird . My guess!!.
Reg Clark
Belrose , NSW.
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