Tuesday, April 16, 2013

Spring bird banding begins

After a long, drawn out winter that all the forecasts got wrong, including the groundhogs, cold conditions were the theme of the first week of banding at Lake St. Clair Metropark (aka the Metro Beach banding station). In late March, four volunteers met me, and the park's head groundskeeper, to remove the dead ash tree that had fallen across the net lanes out in the field. It was quite an effort as the two main trunks had to be cut into multiple pieces so we could drag them out of the lane, off to the side where hopefully they will provide perches for birds. It was also clearly still winter! It was only a little better on the official setup day, Saturday, April 6 as the temperatures started just above freezing, and there was a steady wind. But at least there was no precipitation. And the banding area was nearly devoid of water, a remnant of last year's drought which did not end until October. It was the driest (though still muddy) it has ever been.

In the intervening week, there was considerable rain. So much so, that the first scheduled full day of banding on April 10 had to be canceled. The result was that by the actual first full day of banding, Saturday, April 13, water levels in the banding area were near normal. Temperatures were again low, with a trace of rain, then snow early in the morning, and again in the early afternoon. Then, in mid-morning, an intense period of precipitation lasting at least 10 minutes occurred, and we quickly got the nets closed with no birds caught in them. The precipitation was like small hail or tiny ice balls. It appears that what was falling is called Graupel. Click here for a description of how this precipitation forms. I can't remember ever experiencing this phenomenon before.

Thanks very much to the following volunteers who made banding on these two days possible: Jacob Charlebois, Steve Mangas, Scott Nottmeier, Anne Ross, Edie Schmitz, and Blanche Wicke.

On Saturday, April 6, we met at 8 a.m., later than the normal 6 a.m., because we were positioning the nets for the first time in the season and wanted to take our time, and to be able to work in daylight.
Setting up the Upland Nets
Photo by Scott Nottmeier

As expected, the number of captures on this day was low, with a total of 14 banded, and the bird of the day was a Song Sparrow that had originally been banded in 2011.
After hatch-year Song Sparrow

The purpose for starting this early in the season is to band some of the earliest migrants, as well as some later lingering winter birds. Last year, the extremely warm winter, and even warmer spring, meant that almost all these species were missed, or banded in very low numbers. One of those wintering species that typically departs by April 20 is the American Tree Sparrow, and we were happy to catch one today.
After hatch-year American Tree Sparrow

After hatch-year American Tree Sparrow

The bird of the day, a species that overwinters in small numbers and migrates early in April, was Golden-crowned Kinglet, with 9 banded for the day. Last spring, only one was banded the entire season! The 2004-2012 annual average is about 11, so it is shaping up to be a good spring for this species.
After hatch-year female
Golden-crowned Kinglet

Another species that often winters in the park, and the banding area, in small numbers but migrates later in April and early May (in large numbers) is the White-throated Sparrow. Most years, none are captured before about April 20, so it is likely that the two caught today were overwintering individuals. Another clue that this may be the case is the disheveled look to them, as they were both undergoing extensive body molt, which this species completes before it migrates north in the spring. Only winter resident individuals would look like this now...the later migrants will look pristine.
Second-year White-throated Sparrow

Interesting birds observed, but not banded today included two Turkey Vultures, two Northern Harriers, and a singing resident Carolina Wren.

On Saturday, April 13 we were met with the wet and muddy conditions we've come to expect over the years, so everyone got the expected workout by slogging around the 1/4 mile route every 30 minutes to check nets.
Slogging through the swamp woods to the
Field Edge nets. Photo by Scott Nottmeier

Banding highlights included two Eastern Phoebes, which is a species that is only banded in early to mid-April here, so we always hope to catch them as they are one of the earlier migrants. Last spring, only one was banded the entire season.
After hatch-year Eastern Phoebe

Brown Creepers, likewise, are only banded during the month of April, and today's single capture was right on time for arrival, though actually a couple individuals did overwinter in the banding area this year.
After hatch-year Brown Creeper

After hatch-year Brown Creeper

Although they are resident in the area, we don't catch Carolina Wrens every year, so it was nice to catch this one, which was banded last fall as a hatch-year bird.
After hatch-year Carolina Wren

The Winter Wren is another April migrant, and today's individual represented another on-time arrival.
After hatch-year Winter Wren

Fox Sparrows are always popular with the banding volunteers, as they are not often seen well in the field, and they are another of the early migrants we hope to band in early April. Last spring, only one was banded the entire season, so the three today were a notable improvement...and a sign that we had a "normal" winter for a change and most of these species are back to their normal migration schedules; perhaps even a bit late!
After hatch-year Fox Sparrow

After hatch-year Fox Sparrow

And finally, a couple of Song Sparrows were banded today, the first of many more to come. But the recaptured one was special, as it had originally been banded on September 24, 2007 as an after hatch-year, sex unknown. In 2008, he was recaptured and his sex was determined; male. Today he was not showing any characters that would allow his sex to be determined. Undoubtedly he will soon develop a cloacal protuberance. Presuming he hatched in June 2006, he is now at least 6 years 10 months old, but he could be older. Since being banded in 2007, he has been recaptured every year, often several times, so that today's capture was his 22nd time! This is the only band number that I have completely memorized over the years!
After hatch-year male Song Sparrow
Band Number 2281-10323

Interesting birds observed, but not banded today included two flyover Common Loons, and flyover American Wigeon (1), Northern Shoveler (3), Northern Pintail (6), and Common Merganser (7). Normally we don't get this many individuals, or species of waterfowl over the station. Also of interest was an American Kestrel perching frustratingly close to the field nets, and three Wilson's Snipe winnowing overhead for most of the morning. An American Woodcock called once before daylight. A Forster's Tern flew over, which is a bit early for the species, and the 5 Yellow-bellied Sapsuckers in the banding area are the most I've ever seen in this small (7 acre) area. Rounding out the early migrants that were not captured was a single Hermit Thrush and three Yellow-rumped Warblers.

Banding Data
SATURDAY, April 6, 2013
Sunrise (E.S.T.): 6:07
Time Open (E.S.T.): 8:00
Time Closed (E.S.T.): 13:00
Hours Open: 5.0
No. of Nets: 4.5-13.5
Net Hours: 60.50
Temperature (F): 34-46
Cloud Cover: 100%
Wind: SE @ 7-10-12 mph
Barometer: 29.51-29.53
Precipitation: None
No. Banded: 14 (plus 2 recaptured and 1 released unbanded)
No. of Species: 6
Capture Rate: 28.1 birds per 100 net hours
Volunteers (worked 7.50 hours, 7:00-14:30): Jacob Charlebois, Steve Mangas, Scott Nottmeier, Anne Ross, Edie Schmitz, Blanche Wicke.

Downy Woodpecker - 1
Black-capped Chickadee - 1
Golden-crowned Kinglet - 9
American Tree Sparrow - 1
[Song Sparrow - 2 recaptured, 1 released unbanded]
White-throated Sparrow - 2

SATURDAY, April 13, 2013
Sunrise (E.S.T.): 5:55
Time Open (E.S.T.): 5:45
Time Closed (E.S.T.): 13:00
Hours Open: 6.25 (closed from 9:00-10:00 due to graupel)
No. of Nets: 4.5-13.5
Net Hours: 76.125
Temperature (F): 37-43
Cloud Cover: 100%
Wind: WSW @ 7-10-15 mph
Barometer: 29.16-29.22
Precipitation: Int. rain and snow, and graupel from 9-10 a.m.
No. Banded: 20 (plus 9 recaptured and 4 released unbanded)
No. of Species: 12
Capture Rate: 38.1 birds per 100 net hours
Volunteers (worked 9.5 hours, 5:00-14:30): Jacob Charlebois, Steve Mangas, Scott Nottmeier.

Eastern Phoebe - 2
[Black-capped Chickadee - 2 recaptured]
Brown Creeper - 1
[Carolina Wren - 1 recaptured]
Winter Wren - 1
Golden-crowned Kinglet - 6
American Robin - 1 (plus 1 released unbanded)
Fox Sparrow - 3 (plus 1 released unbanded)
Song Sparrow - 2 (plus 1 recaptured)
Northern Cardinal - 1
Red-winged Blackbird - 4 (plus 1 released unbanded)
American Goldfinch - 3 (plus 5 recaptured and 1 released unbanded)

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