Sunday, May 31, 2009

Metro Beach banding report - May 29, 2009

Although there is likely another week of migration activity, the spring songbird migration is coming to an end. This was represented nicely by the females captured today. As many birders know, the males migrate north first to establish and claim the best territories, and the females often follow later. The unusually large number of birds released unbanded today was due to the escapes of blackbirds and grackles from the nets just as we arrived to extract them. There will be one more banding report, hopefully covering two more banding days in the first week of June where we may capture a few more late warblers, and possibly more Empidonax flycatchers.

Banding highlights for Friday, May 29 included several Wilson's Warblers, including three females.

Second-year female Wilson's Warbler

Only the second Canada Warbler of the spring was captured, this one also a female.

After hatch-year female Canada Warbler

And an American Redstart was captured also, but this one was a male despite being in gray, white, and yellow plumage. Some birders don't realize that this species takes two years to attain the black and orange 'adult' male plumage, and so pass off a lot of second-year (first year in field guide terminology) males. This individual would be easily sexed as male in the field by noting the black blotches on the crown and especially in front of the eye, which females do not show. And of course these second-year males sing, which females do not do.

Second-year male American Redstart

A male Mourning Warbler and a female Magnolia Warbler rounded out the migrant warblers captured today. It was another good day for Red-winged Blackbirds (the season total is now 133, well ahead of last year's record of 92). And three Common Grackles were captured on the last net run, including this nicely iridescent male, which took a good hunk of flesh out of one of my fingers during the brief photo session!

After second-year male Common Grackle

Interesting birds observed but not banded included a rather late Black-and-white Warbler that was unusual for another reason. It appeared to be a melanistic individual, as it was completely normal in plumage on the back, wings, and tail, but the head and breast were unusual. The crown was solid black, with no white median crown stripe, and the cheeks, throat, and breast were medium gray with no sign of streaks or the normal face pattern. Only poor photos were obtained of this odd bird, and the best of them is posted below.

Melanistic Black-and-white Warbler

Since posting this blog on May 31, I received an e-mail from Ben Coulter who forwarded me a photo of a similar Black-and-white Warbler that he photographed at Presque Isle State Park, PA, in 2003. His bird is blacker on the entire head, and shows distinct streaking on the flanks, unlike this bird.

Also of interest was a "V" of about 35 Canada Geese heading north, rather late but most likely undergoing "molt migration", as well as singing Yellow-bellied and Alder Flycatchers in the swamp and marsh. At least two Tennessee Warblers were singing in the area today too, but avoided capture (the 1990-1999 capture rate was ten times my current capture rate for this species!).

A non-avian oddity caught our attention yesterday, as sometimes happens (see the Big Brown Bat photos from a late April posting). Today, an odd "bug" was seen crawling along the road. It was originally identified by me as a dragonfly nymph, but several comments have indicated it is not. The leading contender is that it is the larva of a Predaceous Diving Beetle (Family Dysticidae). I tend to agree with this assessment. Others have called it a "helgrimite" which is a colloquial name for Dobsonfly larva (Family Corydalidae). These are entirely aquatic at this stage of their life, so seeing one crawling along the dry gravel road was bizarre. We figured it had been captured in the water by a bird (grackle?) but when it reared its fearsome head, like something out of a sci-fi movie, the bird may have dropped it into the road. I returned it to the roadside pond after taking photos and avoiding getting bitten.


Predaceous Diving Beetle larva (Dysticidae), species unknown

Many thanks to the volunteer assistants who made banding today possible: Chris Charlebois, Jean Gramlich, and Dave Lancaster.

==========================================================
Banding Data: ==========================================================
FRIDAY, MAY 29, 2009
Sunrise (E.S.T.): 5:00 a.m.
Time Open (E.S.T.): 5:45
Time Closed (E.S.T.): 13:15
Hours Open: 7.50
No. of Nets: 5.00-13.25
Net Hours: 93.00
Temperature (F): 56-73
Sky: 50-0% cloud cover
Wind: WNW-W @ 3-5-12 mph
Barometer: 29.85 - 29.86
Precipitation: None
No. Banded: 36 (plus 20 recaptured and 8 released unbanded)
No. of Species: 19
Capture Rate: 68.8 birds per 100 net hours
Assistants: Chris Charlebois, Jean Gramlich, Dave Lancaster

"Traill's" Flycatcher - 1
[Willow Flycatcher - 1 recaptured]
House Wren - 1
[American Robin - 2 recaptured]
Gray Catbird - 1 (plus 2 recaptured)
Yellow Warbler - 3 (plus 3 recaptured and 1 released unbanded)
Magnolia Warbler - 1
American Redstart - 1
Mourning Warbler - 1
Common Yellowthroat - 4 (plus 1 recaptured and 1 released unbanded)
Wilson's Warbler - 5
Canada Warbler - 1
[Song Sparrow - 3 recaptured]
[Swamp Sparrow - 1 recaptured]
[Northern Cardinal - 2 recaptured]
Red-winged Blackbird - 10 (plus 4 recaptured and 3 released unbanded)
Common Grackle - 3 (plus 3 released unbanded)
Brown-headed Cowbird - 1
Baltimore Oriole - 2 (plus 1 recaptured)
American Goldfinch - 1

6 comments:

Nick B said...

Allen,

Not sure what your invertebrate is exactly (I caught something at the Indiana Dunes BioBlitz but can't remember what they got called), but it's not a dragonfly larva. Good examples of dragonfly larvae here: http://bugguide.net/node/view/95208/bgimage.

Richard Quick said...

Allen,
Does the Redstart have a "dent" in the upper bill? Julie Craves has done some work with bill deformities. What do you think?

Jerry Jourdan said...

Interesting comment about the Canada Geese, Allen. Will and I saw a 'line' of Canada Geese heading due north along the Lake Erie shoreline Saturday morning and commented about the timing...

Jerry

Allen Chartier said...

Guys, As you may note, the "bug" has been properly identified as probably a Predaceous Diving Beetle larva. The redstart does not have a "dent" in the bill, this is the normal depression in the vicinity of the nostril that most passerines show...just an odd angle on the bird perhaps. And, the "migrating" Canada Geese may not be too unusual because they are known to undergo "molt migrations" after they're done breeding and birds banded in Michigan have been found in southern James Bay when molting.

tony gallucci said...

not positive for inability to see the whole critter, but your bug looks to me more like a hellgrammite, see here:
http://bugguide.net/node/view/185765/bgimage

which is the larval form of the dobsonfly, see here:
http://bugguide.net/node/view/210737/bgimage

Allen Chartier said...

I have done some additional research, including looking at an aquatic insects guide, and it appears that the strange invertebrate is actually a larval Predaceous Diving Beetle, probably in the genus Cybister. It did not have the "spines" on the sides of the abdomen shown by larval dobsonflies (helgrammites).