Powdermill Nature Reserve
Pictorial Highlights
July 2004
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Tuesday, July 13th - Sunday, July
18th: We banded on five days this week
and, with weather cooperating and it being an apparently productive year
for local breeding birds, we had some record setting banding totals.
All daily totals but one exceeded our highest daily total for the spring
season. Our biggest day was Saturday,
July 17th, when we banded 131
birds of 34 species,
the second highest daily total for July (our all-time record high total
is 151 on July 29, 1977). There was an obvious, and not unexpected,
shift in the age structure of our catch this week, with over 80% hatching
year birds among the 224 birds banded over the weekend. With
more than a week of banding to go in July, these totals bring us excitingly
close to our highest summer banding total ever in the history of the Powdermill
banding program. With so many birds, of course, there were many highlights.
We've tried to include as many as possible in the pages below. We
thank
Larry Barth, Randi Gerrish, Jim Gruber,
Dan Hinnebusch, and Paul
Sweet for their help this week with banding.
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We owe much of our success this
week to the American Redstart, which was the top species by far with 63
banded (maximum of 29 on Saturday, July 17). HY redstarts, in particular,
are very variable in their plumage, and the sex of some birds cannot be
confidently determined by plumage. The photo below is of one of the
more obvious HY males banded this week, with its well defined gray cheek
patch and very orange-yellow feathers on its sides.
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One reason for the highly productive
breeding season (which is evidenced in the number and percentage of HY
birds we're catching) is that weather this spring and summer was ideal
for primary (i.e., plant) production, which, in turn, apparently supported
very good insect and fruit crops, providing abundant food for nestling
and fledgling birds.
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Moths of many kinds, for example,
seem to be particularly abundant this year. To show that we notice
and appreciate more than just birds here at Powdermill (O.K.,
yes maybe we are a little biased for winged things!), here are pictures
of a couple of moths that caught our eye on the wall of the banding lab
one morning: Clymene moth Haploa clymene
(left) and an unusual
underside view of what we think was a Blinded Sphinx moth Paonias excaecatus
(right).
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Eight new bird species were added
to our summer banding list during the week, three of which are pictured
below.
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Pictured first is one of three hatch
year (HY) Belted Kingfishers banded on Saturday. The bottom two photos
compare the lower breast band of a female (left) and male (right).
The extent of the lower breast band in males is variable, but it is never
complete as in females and often is absent altogether. Also, note
the rust colored tips on the gray upper breast band, an HY characteristic.
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Next, an HY Eastern Kingbird of
unknown sex.
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Finally, this HY female Orchard
Oriole, which was a good find in that we have only ever caught this species
during four other summer seasons in past 43 years.
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We banded four
Black-and-white Warblers this period. The two pictured below are
both HY birds; a female on the left and a male on the right. First
fall females are tinged buffy (especially on the flanks) and have indistinct
streaking on their sides; males lack buffy coloring and have broad, distinct
black and white streaks on their sides. Neither adult nor immature
fall males have a black throat.
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Tuesday, July 6th - Sunday, July
11th: Nets were open on four days this
week and large numbers of fledged birds boosted our total to 167 birds
banded of 34 species. Weather has, for the most part, cooperated
and allowed banding on most days to continue well into the late morning,
at least an hour more than most days during our spring season. Five
new species were added to our summer list, four being hatch year birds
and one being our first "true" fall migrant. Mike
Comley, Dan Hinnebusch,
and Jake Mohlmann helped with banding this
week--Thank You!
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To celebrate our nation's Independence
Day, we color-banded the first Louisiana Waterthrush caught after the 4th
of July (on July 6th) with red, white, and blue! This hatching year
bird of unknown sex became the 46th LOWA to be banded this year as part
of an ongoing study of Louisiana
Waterthrush breeding ecology on nearby streams. The productivity
of this species, closely monitored by field assistant, Felicity Newell,
from Chatham College, was the highest we have ever recorded in nine years
of monitoring the nesting success of the species here at Powdermill.
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The photo below is of two hatching
year (HY) Louisiana Waterthrushes banded on July
11th. This photo illustrates the difference
between juvenal plumage (top bird) and first basic plumage (bottom bird).
Both birds hatched this year, but the differences in plumage reflect wide
differences in the hatching date of the two birds. The very loosely
textured and unstructured feathers of the bird on the top (notice, in particular,
the undertail coverts) are juvenal. The fresher, more structured
adult like feathers on the bottom bird are a result of its first prebasic
molt. Fledglings begin to molt in their first basic feathers by about
their second week out of the nest. The molting process can then take
three or four weeks to complete. This makes the hatching date for
the bottom bird about a month earlier than the top bird, which had yet
to begin its prebasic molt.
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One of our new species for the summer
was this HY Canada Warbler of unknown (but probably female) sex.
First fall males generally have a more distinct necklace usually with some
black. This bird was too intermediate, however, in both plumage
and wing length for us to confidently sex.
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A second new species for the summer
and also the first of our "true" fall migrants was the Least Flycatcher.
Pictured below is a second-year (SY) adult female (top) and an after-second
year ASY adult male (bottom). The SY bird had very worn retained
juvenal primaries, primary coverts, secondaries and rectrices (except secondaries
7-9 and the central tail feathers, which were replaced in the spring during
the prealternate molt (detail of molt limits in third photo below).
Flycatchers aren't always photogenic, so we were pleased to get these nice
shots of a couple of unusually cooperative birds.
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This week was full of photo opportunities
and highlights. One of which came within the same net round on July
8th. House Finches and Purple Finches
(both new for the season) can propose an ID challenge for birders and banders,
especially in the case of juveniles like the two birds pictured below.
The House Finch (left) has a more parrot-like curved upper mandible than
the Purple and lacks the distinct ear patch and eyebrow of the Purple Finch
(right). Immature House Finches acquire adult coloring after their
first fall molt, at which time they can be sexed. The HOFI pictured
below, still in full juvenal plumage, was recorded as sex "unknown."
Purple Finches have "delayed plumage maturation," meaning that the males
do not acquire adult male plumage coloration until they are more than one
year old (i.e., after their second prebasic molt). So, unlike the
HOFI, the PUFI pictured below in its juvenal plumage will still be sex
"unknown" even after it completes its first prebasic molt.
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Even with additional photos included
in our Powdermill summer "babies" photo
gallery, we couldn't help but also showcase this Black-and-white Warbler
fledgling on our main page. It was banded on the July 10th as a locally
(L) hatched bird--probably one of the youngest of its kind ever banded
here at Powdermill.
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Tuesday, June 29th - Sunday, July
4th: Nets were again open on four mornings
this week and a total of 95 birds of 29 species was banded, three of which
were new for the season. Mike Comley,
Randi Gerrish, Dan Hinnebusch, and Mike Lohr
all
helped with banding.
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One of our three new species this
week was a hatching year bird which was in a plumage we rarely see at Powdermill.
Any guesses? -- scroll slowly if you're thinking, the second picture
gives it away.
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This hatch year Golden-crowned Kinglet
was found in our nets Wednesday morning in full juvenal plumage, just before
we hosted a group of 31, 7-8 year old kids participating in "Nature Adventures"
summer camp series at Powdermill (photo below). A bird that favors
older growth stands of conifers (adundant in trees >50 years of age), the
Golden-crowned Kinglet was long considered a rare breeding bird for the
state. Reforestation of the once nearly eliminated spruce trees in
Pennsylvania began in the early 1900's, so by the 70's and 80's these trees
were an ideal size and height to invite kinglets back in any numbers as
a breeding bird. Initially found in the forest plantings at higher
elevations, the first PA Breeding Bird Atlas confirmed breeding kinglets
at elevations below 1,000 feet (Mulvihill, R.S. in Brauning, D.W. 1992.
Atlas of Breeding Birds in Pennsylvania. University of Pittsburgh Press,
Pittsburgh). The elevation at Powdermill is between 1300 and 1400
feet as compared to nearby Laurel ridge which is about 2700 feet.
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Also added to our summer species
list was the first capture of a Veery. Of no surprise, it was another
of the many hatching year birds banded during the period.
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As promised, we have included a
comparison photo of the back plumage of the juvenal Ovenbird banded in
June and this recently (and very late) fledged Louisiana Waterthrush.
We thought this photo was a welcome addition to the discussion of the taxonomy
of these species and supported Dr. Kenneth C. Parkes argument that they
might better be considered separate genera based, among other things, on
the difference in the appearance of their juvenal plumages compared to
adults of the same species. As seen in the photos below, the Ovenbird
(bottom photo) has streaked dorsal juvenal plumage (much of it already
replaced by the prebasic molt in this bird), which does not resemble that
of an adult Ovenbird. Juvenile waterthrushes (top photo), however,
closely resemble the adults in plumage coloration and pattern and differ
only in the structure of the feathers. Click
here to read the full discussion in pictorial highlights from June
2004.
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We've added pictures of July "babies"
to our summer photo gallery. Click
here for the photo gallery of fledgling birds banded at Powdermill
Nature Reserve over the past two months.
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The links below
are for some additional photos of birds banded at Powdermill during July
that were not included in the main page above.
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Last Updated on 7/23/04
By Adrienne J. Leppold