The warbler and thrush migrations have begun but are still just a trickle, and the flycatcher migration seemed to be in a pause this week, while sparrow migration is still a couple weeks from beginning (the number of juvenile Swamp Sparrows this August was down again for the second year in a row). Hummingbird migration should reach its peak this coming week.
Highlights of the 59 birds banded on Monday, August 29 included this hatch-year male Downy Woodpecker that was still young enough to be showing red on the top of the crown, which females also show at this age but are distinguishable by lacking red on the nape.
 |
| Hatch-year male Downy Woodpecker |
Many birds leave the nest in a juvenile plumage that is molted before migration or winter; note the Common Yellowthroats with buffy throats and cinnamon wingbars mentioned in previous posts, and the spotty juvenile American Robins that pretty much everyone has seen by now. Downy Woodpeckers, in addition to molting the feathers on the head also molt their wing feathers. This individual still had its worn juvenile outer three primaries (p8-p10), while the 7th primary was in the process of being replaced.
 |
| Hatch-year male Downy Woodpecker |
New warbler arrivals today included two Nashville Warblers.
 |
| Hatch-year female Nashville Warbler |
Two male Black-throated Blue Warblers were also nice to see, in the Swamp Nets where we seem to catch a majority of them.
 |
| Hatch-year male Black-throated Blue Warbler |
And the first Blackpoll Warbler of the season was right on time. The crown feathers are messed up on this individual because I was blowing them aside to check the skull ossification to determine its age. Sometimes I forget to "preen" the bird before taking a photo.
 |
| Hatch-year Blackpoll Warbler |
Among resident species, there have been fairly good numbers of young Common Yellowthroats banded in the past month. Most of the hatch-year birds cannot be sexed, but the one below was clearly a male based on its mottled black cheeks.
 |
| Hatch-year male Common Yellowthroat |
Interesting birds observed but not banded included two juvenile Cooper's Hawks circling together over the marsh, a flyover Caspian Tern, a single calling Great Horned Owl before dawn, a singing Carolina Wren, and Black-and-white and Wilson's Warblers. An insect also makes the list of highlights for today. Mottled Darners were only confirmed in Macomb County last fall, based on individuals caught in the mist nets. They were back again this year, with three of them caught (two released successfully). This species seems to be somewhat crepuscular as they're only around in the early morning, and in the more shady areas of the woods.
 |
| Mottled Darner (Aeshna clepsydra) |
Highlights of the 70 birds banded on Saturday, September 3 included 12 Ruby-throated Hummingbirds, including the 50th of the season. This is well ahead of the pace of the two best years for the species when 50 was reached on 10-Sep-06 and 9-Sep-07. In more recent years, the 50th hummingbird was banded on 8-Sep-08, 6-Sep-09, and 8-Sep-10. Perhaps 100 will be banded this fall for the first time at this locale?
 |
| Hatch-year male Ruby-throated Hummingbird |
A Northern Flicker was only the second one for the fall, which is about average. Unfortunately, he wasn't terribly cooperative for photos. A resident species banded today that isn't banded very often, though perhaps with increasing frequency, is White-breasted Nuthatch.
 |
| After hatch-year female White-breasted Nuthatch |
One of my favorite warblers to quiz (taunt?) banding volunteers and passing birders was captured today. See if you can tell what it is from the photo below before continuing.
This bird is a very good lesson in not relying on a single field mark to identify a species. There is quite a range of variation among individuals, some based on age and sex but not always. In this case, the primary field mark that birders would use for identification is almost entirely missing! Now what? Well, how many warblers have a dusky gray cheek with a narrow white line over the eye and a small white eye-arc below? Well, Yellow-rumped Warbler does, but that species has wing bars and tail spots, while this bird is very plain above and below. That leaves only female Black-throated Blue Warbler. The white spot at the base of the primaries can be much reduded (as here) or even missing entirely in some hatch-year females.
Four more Wilson's Warbler were captured today, including this hatch-year male. The amount of black in the crown varies, with some adult females showing as much as this young male. So it is important to age the bird first.
 |
| Hatch-year male Wilson's Warbler |
It was nice to catch another Canada Warbler since we may be past the peak of their migration in this area. This individual was aged hatch-year based on incomplete skull ossification, and sexed as male based on the small black spots on the breast. Hatch-year females often have no spots on the breast, or dusky ones, not black.
 |
| Hatch-year male Canada Warbler |
 |
| Hatch-year male Canada Warbler |
Interesting birds observed but not banded included the first calling Eastern Screech-Owl of the season (at around 9 a.m.!), along with a single Great Horned calling. Both Eastern Wood-Pewee and Warbling Vireo were singing near the Upland Nets today but perhaps won't be much longer. A Tufted Titmouse was calling in the area too; a species that is very irregular in the banding area, and one of the presumed summer resident Blue-gray Gnatcatchers was also heard calling today.
Banding could not have been conducted this week without the help of great volunteers, and I especially appreciate the last-minute volunteers who turned up on Saturday morning. It made taking down the nets in 90-degree temperatures much easier than it might have been. Thank you everyone!
============================
Banding Data
-------------------------------------
MONDAY, August 29, 2011
Sunrise (E.S.T.): 5:54
Time Open (E.S.T.): 5:45
Time Closed (E.S.T.): 12:30
Hours Open: 6.75
No. of Nets: 4.50-13.50
Net Hours: 86.375
Temperature (F): 58-73
Cloud Cover: 50-25-60%
Wind: NW @ 1-3 mph
Barometer: 30.02-30.09
Precipitation: None
No. Banded: 59 (plus 15 recaptured and 1 released unbanded)
No. of Species: 18
Capture Rate: 86.8 birds per 100 net hours
Volunteers (worked 9.5 hours, 5:00-14:30): Dave Lancaster, Jeremy Miller, Joan Tisdale.
Ruby-throated Hummingbird - 10 (plus 1 released unbanded)
Downy Woodpecker - 1
[Willow Flycatcher - 2 recaptured]
"Traill's" Flycatcher - 1
Warbling Vireo - 2
Swainson's Thrush - 1
American Robin - 2
Gray Catbird - 3
Nashville Warbler - 2
Chestnut-sided Warbler - 1
Magnolia Warbler - 1
Black-throated Blue Warbler - 2
Blackpoll Warbler - 1
American Redstart - 3
Common Yellowthroat - 3 (plus 4 recaptured)
Song Sparrow - 3 (plus 1 recaptured)
Red-winged Blackbird - 8 (plus 2 recaptured)
[Baltimore Oriole - 1 recaptured]
American Goldfinch - 15 (plus 5 recaptured)
-------------------------------------
SATURDAY, September 3, 2011
Sunrise (E.S.T.): 5:59
Time Open (E.S.T.): 5:45
Time Closed (E.S.T.): 13:00
Hours Open: 7.25
No. of Nets: 4.50-13.50
Net Hours: 91.875
Temperature (F): 73-90
Cloud Cover: 90-20-50%
Wind: Calm-SE @ 0-3-7 mph
Barometer: 29.97-29.87
Precipitation: None
No. Banded: 70 (plus 16 recaptured and 2 released unbanded)
No. of Species: 21
Capture Rate: 95.8 birds per 100 net hours
Volunteers (worked 9.0 hours, 5:00-14:00): Mary Buchowski (6.5 hours), Terri Chapdelaine, Chris Charlebois, Jacob Charlebois, Steve Longstreth, Tom Schlack, Judi Wade (1 hour).
Ruby-throated Hummingbird - 12
Downy Woodpecker - 1
Northern Flicker - 1
Black-capped Chickadee - 1 (plus 1 recaptured)
White-breasted Nuthatch - 1
Veery - 1
Swainson's Thrush - 3
American Robin - 5
Tennessee Warbler - 1
Magnolia Warbler - 2
Black-throated Blue Warbler - 1
American Redstart - 1
[Northern Waterthrush - 1 recaptured]
Common Yellowthroat - 3 (plus 5 recaptured)
Wilson's Warbler - 4
Canada Warbler - 1
Song Sparrow - 7 (plus 2 recaptured)
[Northern Cardinal - 1 recaptured]
Red-winged Blackbird - 2 (plus 1 recaptured)
House Finch - 2
American Goldfinch - 21 (plus 5 recaptured and 2 released unbanded)
1 comment:
While I may not comment on every post, I find that I am learning a great deal from your efforts. Thanks again. Rich Vial
Post a Comment