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Michigan Hummingbird Banding Summary 2002
Overview
Ruby-throated Hummingbirds were banded in Michigan for the second
season, with the difference that effort was begun earlier in the year,
providing data for spring, summer, and fall. In Michigan, a total of 196
Ruby-throated Hummingbirds was banded and one Rufous Hummingbird was
captured that had been banded previously in Louisiana. Most effort was
with a single Drop Door Cage Trap, though at one site a Russell Trap was
used. Thirty-seven sites were visited in Oakland, Washtenaw, Jackson,
Jackson, Livingston, Wayne, Monroe, Van Buren, Cass, Kalamazoo, and
Berrien counties. A total effort of 136.50 hours on 53 days was about
twice the effort last year. This resulted in an average of 1.44 birds
banded per hour of effort. More than 4,000 miles were driven in these
efforts.
The project was expanded into Ohio in search for wintering and
vagrant hummingbirds, and resulted in five Rufous Hummingbirds and one
Calliope (a first state record) being banded, as well as one Rufous
captured that had been banded previously in South Carolina. One
Ruby-throated Hummingbird was banded in Ohio. In general, the late
lingering Rufous Hummingbirds were quickly captured, most in about 15
minutes, so a total of only 2.0 hours of effort for all these birds on
five days was required to capture these birds. More than 2,000 miles
were driven in these efforts.
Spring Migration
Weather conditions in Spring 2002 were very difficult for migrating
hummingbirds. Although there were arrivals noted as early as 15 April,
the main arrival is typically the first week of May each year.
Temperatures were well below normal in the first half of May, and
conditions were also very wet, even including snowfall as late as 17 May
in the southern parts of the state. Several observers reported dead
hummingbirds in early May, including birds seen dropping dead off feeder
perches, and two dead males were gathered from homeowners and donated to
the University of Michigan Museum of Zoology, Ann Arbor under my salvage
permit. Northward migration typically proceeds at a brisk pace, and
attempts to band birds during May often resulted in the birds no longer
being present the following day. The number of hummingbirds banded in
spring was very low, with only 10 banded at five sites between 10-29
May. Five were adult males, one was a second year male, and four were
adult females.
Nesting Season
Generally, the nesting season begins in earnest in early June, with
birds even beginning nest building in late May. In 2002, however,
migration continued through the first week of June as evidenced by color
marked birds not remaining at one banding site in Oakland County. The
cold wet spring undoubtedly delayed the onset of nesting, and the
drought that followed in June and July almost certainly caused extensive
nest failures. The number of females in breeding condition late in the
summer supports this idea, with many birds apparently having to re-nest
later in the summer.
A single returning female was encountered in southwest Ann Arbor on
21 June carrying an egg, visible through the thin skin of her abdomen.
She was originally banded on 16 August 2001 at a residence ¼ mile to
the east.
In Van Buren County, a nest was located in a Maple tree 11 feet off
the ground in a homeowners back yard. On 31 July the two nestlings were
banded at an estimated age of 17-18 days, very near the time when they
should have departed the nest. Four days later, the two nestlings did
successfully leave the nest. Photos of these birds can be found at VAN2.
In most years, adult males would begin southward migration in late
July after undergoing a molt of body feathers. But, the molt schedule
this year, primarily in August, seemed to indicate that males departed
later than that this year. A total of 96 adult birds were banded between
4 June and 31 July.
Fall Migration
Between 1 August and 30 September a total of 89 Ruby-throated
Hummingbirds were banded, with 22 at a migration banding station at Lake
Erie Metropark, Wayne County. Of the 89, 39 were hatch-year birds, which
seems quite a low proportion, though there is not yet enough data for
comparisons. The apparent late breeding season resulted in observers
reporting unusual numbers of hummingbirds lingering into October, and
even November. One was banded on 11 October in Wayne County, and two
were banded on 6 November in Berrien County, with one of them remaining
till 21 November, a record late date for the state.
Vagrant Hummingbirds
Michigan had two vagrant hummingbirds in 2002. The first was the state's
second ever Green Violet-ear at Topaz, 5 miles east of Bergland,
Ontonagon County on 11-14 August. Photos of this bird can be found by
clicking here and scrolling to the
bottom of the page. This was a truly amazing record, as there are no
other states other than Texas and Arkansas with more than one record of
this Mexican species.
More expected was the single Rufous Hummingbird that arrived in Berrien
County some time in August, but which was not reported until early
November. On 6 November I went to band the bird, and it turned out that
it was already banded. It had been banded originally on 28 January 2001
in St. Rose, Louisiana by Nancy Newfield when it was molting from
juvenile to adult plumage.
Rufous Hummingbirds, and unidentified Selasphorus hummingbirds were
much more numerous in adjacent Indiana (5-6 reports) and Ohio (13
reports, 10 confirmed as Rufous). In Ohio, I expanded the scope of the
Michigan HummerNet to assist with the identifications, aging, and sexing
of these birds, with the result that I captured six Rufous Hummingbirds.
Most amazing was an adult female that was captured on 29 November near
Columbus, which had been banded previously on 20 November 2001 in York,
South Carolina by Bill Hilton, Jr. as a juvenile female. Incredibly, of
the 9 Rufous Hummingbirds I've captured since fall 2001, three have been
banded previously, an incredibly high number, and proof that efforts to
capture these wanderers can help us learn more about their movements.
On 1 November an unidentified hummingbird was captured and confirmed
as the first ever Calliope Hummingbird for Ohio. The bird was a juvenile
male, and appeared to be in poor health. Likely due to this, it expired
in hand without warning. Such risks to the birds are always possible
when handling them, but typically it is an extremely infrequent
occurrence. This was the second hummingbird to expire among the hundreds
handled and banded for the project since 2001. The bird was transferred
to the collection of the Ohio State University where it will provide
permanent evidence of the species' occurrence in the state. An
experience like this is personally very devastating, but after
considerable thought I have realized that without continuing studies of
this nature we will not learn what we need to learn about hummingbirds
in order to protect them and their habitats. So the Michigan HummerNet
will continue, attempting to learn more about Ruby-throated Hummingbirds
in Michigan, and seeking out vagrant hummingbirds again in Ohio and
expanding into Indiana for 2003.
Acknowledgments
I wish to thank all of my "hummer hosts" for allowing me
to come onto their property to band hummingbirds. A special thanks to
the staff at Lake Erie Metropark and at the Rouge River Bird Observatory
for allowing me to band hummingbirds on their property.
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