Banding Data
Location Code: SAG3
Click here to view written description.
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Description |
Species:
Rufous Hummingbird (Selasphorus rufus), adult female Date &
Time: November 17, 2008.
First observed by homeowner on 12 November 2008 and last observed
on 5 December 2008. I arrived around 9:00 a.m. and waited about 15
minutes before the bird made an appearance.
I then set up my trap at 9:30 a.m. and caught the bird at 9:33
a.m. The bird was banded and
released at 9:42 a.m. under Federal permit No. 23156, and Location:
At the home of Bernie Coleman in Shields, Saginaw Co. Observer
(s):
Allen Chartier Equipment:
Photographed in-hand with digital camera (attached to this document).
All measurements were made using digital calipers.
Bill corrugations were determined by viewing through a 10x loupe,
as they are impossible to accurately determine any other way. Viewing
conditions: The sky was overcast
and the light diffuse. The bird was banded, measured, weighed, and
photographed outdoors. Description:
When the bird first made an appearance at the feeder, it was
apparent that it was a Rufous or Allen’s Hummingbird, based on peach-rufous
on the flanks, and an irregular blotch of iridescent throat feathers.
This observation was made with my 10x Swarovski binoculars from a
distance of about 30-feet. The bird was then captured for banding, and
it was aged, sexed, and identified in that order.
The proper use of Stiles (1972) for banders requires that an
individual Rufous/Allen’s Hummingbird in-hand be correctly aged and
sexed before a species determination can be made (B. Sargent and N.
Newfield, pers. comm.). Age:
The bird was aged as after hatch-year (adult) based on the
absence of shallow groovings or corrugations on the upper mandible. This
is universally recognized as the most reliable method for age
determination in hummingbirds (Ortiz-Crespo, 1972). Sex:
The upper tail coverts and rump were entirely green. The rufous
on the base of the central rectrix (r1) was restricted to about the
basal 25%, and was completely covered by the green upper tail coverts.
As the bill corrugations indicated the bird was adult, plumage alone is
enough to confirm the bird was a female, but these additional plumage
characters support that this bird was a female. The
wing measurement of 42.93 mm was at the short end of the range given for
adult and immature female Rufous given in Stiles (1972). It is also near
the large end of the range for immature males, so the wing chord
measurement weakly supports the sex of this bird as female. The
bill measurement (exposed culmen) can sometimes be helpful for
determining sex as indicated in Table 1 in Stiles (1972). This bird’s
exposed culmen measurement of 17.05 mm was near the middle of the range
given for adult and immature females Rufous. It is also near the large
end of the range for immature males, so the exposed culmen measurement
supports the sex of this bird as female. The
pattern of iridescent gorget feathers on the throat can sometimes be
helpful in determining the sex of Selasphorus
hummingbirds. This bird had 17 clustered together in the center of the
throat (see photos). This
pattern is more indicative of females than males, though the number of
iridescent feathers varies considerably and is not particularly useful
for supporting an age determination.
Species:
Given that the bird was an after hatch-year (adult) female, using
Stiles we can determine whether this bird was a Rufous or Allen’s
Hummingbird using several additional measurements and observations.
The presence of notching and/or emargination on the second
rectrix from the center (r2) is one feature that can often be observed
in the field to confirm Rufous, and is considered diagnostic. This
individual had noticeable notching and emargination on both webs of the
second rectrix (see photos), which confirms that this bird was a Rufous
Hummingbird. Using Figure 3
in Stiles (1972), the shape most closely matched figure Aa. As
additional support for the identification, the widths of two other tail
feathers, the central rectrix (r1) and the outermost rectrix (r5) were
measured. The width of the central rectrix (r1) was measured as 7.67 mm.
This is at the narrow end of the range for adult female Rufous and at
the wide end of the range for both subspecies of Allen’s Hummingbird*
given in Stiles (1972) so is only suggestive of Rufous. The
width of the outer rectrix (r5) was measured as 3.48 mm.
This is broader than the maximum range for immature female
Allen’s (max. 3.3 mm for both subspecies given in Stiles 1972) and so
provides additional conclusive and diagnostic support to the
identification as Rufous. Tail
measurements are often not very useful.
This bird’s tail measurement of 28.5 mm is above the maximum
for adult females of both subspecies of Allen’s (Stiles 1972) and is
at the upper end of the range for adult female Rufous. So tail length is
somewhat useful in this case. Molt:
There was no body molt evident on this bird.
The outer 4 primaries (p7-p10) were old and worn, and the inner
primaries (p1-p6) were recently replaced and contrastingly shiny black.
Rectrices 3 and 4 were worn while r1, r2, and r5 were fresh and probably
recently replaced. Fat/Weight:
The bird had a fat code of 1 (0-3 scale) and weighed 3.41 grams, about
average for an adult female planning an extended stay. Voice:
Brief, sharp chip note when
the bird was released. More strident than Ruby-throated gives. Similar
Species:
Allen’s Hummingbird is the species most similar to Rufous
Hummingbird. On this bird, the diagnostic “notched and emarginated”
second rectrix (r2), measured width of the outer (r5) rectrices were the
primary characters confirming the identification, with tail length and
to a lesser extent the width of the central (r1) rectrix supporting the
identification. Experience:
I have seen dozens of Rufous
Hummingbirds in several states, banded more than 50 in Michigan, Ohio,
Indiana, and Ontario since 2001, handled ~35 in Louisiana in February
2003 with Nancy Newfield, and handled about a dozen in Arizona in 2006
helping other banders. I
have seen several Allen’s Hummingbirds on two trips to When
report was written:
This report was written on December 19, 2008 based on data and
photos taken during the banding process. References
consulted:
None were consulted while observing the bird in the field, nor
were any used to write notes in the field or to write this report.
Stiles (1972) and Pyle (1997) were available during the banding
of the bird. *
There are two subspecies of Allen's Hummingbird.
One is the widespread and migratory nominate subspecies (Selasphorus
sasin sasin) breeding from coastal northern References: Ortiz-COrtiz-Crespo,
F.I. 1972.
A new method to separate immature and adult hummingbirds. Auk
89: 851-857. Pyle,
P. 1997.
Identification Guide to North
American Birds: Part 1. Slate
Creek Press, CA. Stiles,
FStiles, F.G. 1972.
Age and Sex Determination in Rufous and Allen Hummingbirds.
The Condor 74: 25-32.
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