Sunday, June 8, 2014

Metro Beach banding report - Spring 2014 finale

The first week of June is the last week of spring banding at this site every year. Some years there are migrants still moving through, while in other years migration has ended and nesting is well underway in the area. This year, it was mostly the latter, and only one banding day (Friday June 6) could be scheduled due to the limited availability of volunteers. Highlights of that banding day are described below, followed by a brief summary of the entire spring season.

Highlights of the 28 birds banded on Friday, June 6 included a Ruby-throated Hummingbird; this one an adult female that was showing signs of breeding locally.
After hatch-year female Ruby-throated Hummingbird

 A single Empidonax flycatcher was banded today. This one keyed out to Alder Flycatcher, which makes it a likely migrant as they rarely summer here, with Willow breeding annually. It was the only migrant captured today. Banding volunteer, Marie McGee, suggested that I explain how these flycatchers are identified. I hope I can do it accurately and concisely, without being too boring...
After hatch-year Alder Flycatcher

Keying out Willow and Alder flycatchers requires taking a number of precise measurements that can be tricky to obtain on a squirming bird in-hand. The chart below, shown in the Pyle guide that all North American banders use, shows a scatter plot with Willow on one side, Alder on the other, and a zone of overlap along a median line. Along the X-axis is a "wing formula", which is something our European colleagues are used to doing with a number of their warbler species. It consists of the difference between two measurements of primary lengths, all done on the closed wing, which only increases the degree of difficulty. Formula I is the difference between the longest primary and the 6th primary, minus the difference between the 10th primary and the 5th primary; the latter is a negative number of the 10th primary is longer than the 5th. On the bird above, Longest primary minus the 6th was 4.7mm, and p10 minus p5 was -0.5, so the Formula I value is 5.2mm. The Y-axis is the length of the bill measured from the front of the nostrils (nares) to the tip. On this bird it was 7.9mm. So, using the top chart for adults in spring (the bottom chart is only for hatch-year birds in fall), the intersection of these two values is approximately at the tip of the arrow, which is well within the range for Alder Flycatcher. It does take a bit of practice to do this quickly, but accurately, especially on busy days. And, in my experience about 50% of them fall in the overlap zone and remain as "Traill's" Flycatcher.
Figure 149 in Pyle for identifying Willow/Alder Flycatchers

A couple of Common Yellowthroats were banded today, including this female that decided she'd sit in my hand after being released. After about a minute, she flew off strongly.
Second-year female Common Yellowthroat

American Goldfinches have not been in the highlights for a while, and the number of newly banded this spring was only about average (51), after record numbers last year both in spring and fall. Those records surely contributed to the greater than normal number of returnees from previous years, which included: 1 from 2008, 1 from 2011, 3 from 2012, 9 from spring 2013, and 32 from fall 2013.

Similarly impressive numbers of returnees of Yellow Warblers were noted, with a very good total of 38 newly banded plus 27 returning from previous years (1 from 2007, 3 from 2008, 2 from 2009, 3 from 2011, 9 from 2012, and 9 from 2013).

The final bird banded of spring 2013 was this second-year female Common Yellowthroat (the 36th of the spring). She is showing rusty on the forehead that some individuals have.
Second-year female Common Yellowthroat

Interesting birds observed but not banded today included single calling Virginia Rail and Sora, and persistently singing Blue-gray Gnatcatcher, Eastern Wood-Pewee, and Great Crested Flycatcher.

Banding Data
FRIDAY, June 6, 2014

Sunrise (E.S.T.): 4:56
Time Open (E.S.T.): 5:45
Time Closed (E.S.T.): 13:15
Hours Open: 7.50
No. of Nets: 5.0-14.0
Net Hours: 98.00
Temperature (F): 50-73
Cloud Cover: 10-70%
Wind: Calm-SE @ 0-5 mph
Barometer: 30.05-30.05
Precipitation: None
No. Banded: 28 (plus 22 recaptured, 3 released unbanded)
No. of Species: 13
Capture Rate: 42.9 birds per 100 net hours
Volunteers (worked 9.50 hours, 5:00-14:30): Mike Carnill, Robyn Carnill, Dave Lancaster, Marie McGee, Blanche Wicke.

Mourning Dove - 1
Ruby-throated Hummingbird - 1
Alder Flycatcher - 1
House Wren - 3 (plus 2 recaptured)
American Robin - 3
[European Starling - 1 recaptured]
[Yellow Warbler - 3 recaptured]
Common Yellowthroat - 2 (plus 2 recaptured, 1 released unbanded)
Song Sparrow - 1 (plus 4 recaptured, 1 released unbanded)
Red-winged Blackbird - 9 (plus 3 recaptured, 1 released unbanded)
Common Grackle -3
[Baltimore Oriole - 1 recaptured]
American Goldfinch - 5 (plus 6 recaptured)

2014 Spring Banding Season Summary

The spring of 2014 was interesting for some great highlights, but had the lowest number of species banded (59) since banding was re-started here in 2004; and only 5 of the years between 1990-1999 had a lower species total. The 656 individuals banded ranked this spring 7th among the last 11 spring seasons, so well below average. Poor showings of thrushes and warblers contributed, in addition to the profoundly low number of White-throated Sparrows. In some ways, migration seemed to pass us by, even though other locales in southeastern Michigan had a pretty good spring.

Banding Totals (Spring 2014)
Mourning Dove - 3
Ruby-throated Hummingbird - 9
Red-bellied Woodpecker - 1
Downy Woodpecker - 9
Hairy Woodpecker - 1
Northern Flicker - 4
Alder Flycatcher - 7
Willow Flycatcher - 2
"Traill's" Flycatcher - 4
Least Flycatcher - 1
Eastern Phoebe - 1
Warbling Vireo - 3
Blue Jay - 8
Tree Swallow - 8
Northern Rough-winged Swallow - 8
Black-capped Chickadee - 4
White-breasted Nuthatch - 1
Brown Creeper - 8
House Wren - 8
Winter Wren - 1
Golden-crowned Kinglet - 17
Ruby-crowned Kinglet - 5
Veery - 2
Swainson's Thrush - 5
Hermit Thrush - 15
American Robin - 34
Gray Catbird - 5
European Starling - 15
Nashville Warbler - 1
Yellow Warbler - 38
Chestnut-sided Warbler - 1
Magnolia Warbler - 5
Yellow-rumped Warbler - 2
Palm Warbler - 1
Blackpoll Warbler - 1
American Redstart - 2
Northern Waterthrush - 10
Common Yellowthroat - 36
Wilson's Warbler - 6
Northern Cardinal - 3
Indigo Bunting - 1
American Tree Sparrow - 12
Fox Sparrow - 8
Song Sparrow - 24
Lincoln's Sparrow - 8
Swamp Sparrow - 60
White-throated Sparrow - 4
Red-winged Blackbird - 138
Common Grackle - 32
Brown-headed Cowbird - 2
Baltimore Oriole - 15
House Finch - 2
American Goldfinch - 51

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