Wednesday, September 28, 2011

y(Y?)ellow-bellied flycatcher

There have been quite a few recent local reports of Yellow-bellied Flycatcher, a rather rare migrant to North Carolina.  It seems that this is either a great fall to see the species or a great fall to see another of the confusing Empidonax flycatchers, such as a first-year Acadian with yellow-washed belly, and report it as a Yellow-bellied.  

Without hearing birds of this genus vocalize, identification can be quite tricky, and many a cautious birder will stick with Empidonax sp. Even under ideal viewing conditions.  

Take this bird I photographed at Brickhouse Road over the weekend…
 Not a great look, but definitely some sort of empid.  

Moments later I came upon another empid. that may or may not have been the same individual.  This one clearly had a yellow belly, green back and even a yellowish-looking throat. 

I followed it for several salleys along the path and it spent time along the forest edge on both the more mature side as well as the denser, younger wet side.
After a while it took a break from foraging and settled cooperatively for a few minutes in this tree.
What's it doing eating a caterpillar?  I thought these things were supposed to catch flies!
So this post has turned into an ID quiz for which I have no answer key.  Can anybody tell me what this bird is?

Previously I had never seen an immature Acadian nor a Yellow-bellied Flycatcher.  Surely this bird is one or the other… but which?  

If the photos aren’t enough… Check out this video… 

No it doesn't vocalize or do anything super-exciting.  It just looks around, and more importantly stays in focus  (I have several other clips in which my camera decided that a twig was far more interesting.)

I'll admit I'm not flycatcher expert, but I'm starting to lean toward Sierran Elaenia =P

Update 10/14/11:

After consulting carolinabirds and frontiers in bird identification listservs there was no consensus among expert opinion.  I think I got a total of 5 votes for Yellow-bellied and 4 votes for Acadian.  In general folks in the Acadian camp were more confident in their ID.

Jeff Pippen's advice was probably best: go get Ken Kaufman's book and figure it out yourself.  

The section on empids is really helpful for determining which attributes are most useful (i.e. bill size/shape, primary projection) and which are not (i.e. color, tail flicking).  

The main problem with the pictures I posted is that they show more of the less-useful indicators.  I captured the bill from several different angles, but it's size seems to change from one photo to the next.  

The result was a crazy juxtaposition of comments, such as...

Expert A: "...the smaller bill...seems to point towards Yellow-bellied."
Expert B: "The bill is clearly broader at the base, longer, and pointier than Yellow-bellied, Least, or Willow/Alder Flycatchers."

So I went back to my original photos and videos and found that some of my "bad" pictures actually illustrate the important field marks better than the "good" photos above. 

In these photos (of the same individual) the bird here is in direct sunlight and the color is washed out...

...BUT the primary projection is shown much more clearly

...AND it is easier to see the width of the base of the bill.  

The apparently broad bill seems to fit much better with Acadian than Yellow-bellied. 

The primary projection also looks to be long...perhaps not too long to rule out Yellow-bellied on its own, but I think it also favors Acadian.  

So after chasing my tail all over the place and being pulled apart by conflicting opinions, I'm right about where I started with my best guess for the ID.  

Big thanks to everybody who has commented and emailed me about this bird...especially to those who voted for Yellow-bellied Flycatcher!  Unfortunately I don't think I can, in good faith, mark it down as such (especially since it would be a life tick).  

I've certainly learned a lot and hope others have as well.  Also, further comment and discussion is more than welcome.   

Thursday, September 22, 2011

More Falls Lake absurdity

Since classes resumed up birding opportunities have been woefully few and far between for me. The coincidence of the fall semester and fall migration, I suspect, is frustrating for many an academic birder.

So many odd birds have appeared at nearby Falls Lake in the past month it seems that every weekend it just has to be my birding destination.

There was the dark morph Parasitic Jaeger that Jeff Pippen found a couple weekends ago… perhaps the fourth record of the species in the North Carolina Piedmont. It was almost surely a relic from the recent passage of Hurricane Irene.

Here is my awful phone-scoped photo from about a mile away at Hickory Hills boat ramp. The white lump on the right is a Ring-billed Gull and the dark lump on the left is the jaeger.
Parasitic Jaeger with Ring-billed Gull (use your imagination)
Since the species relies on pilfering fish from other seabirds and there were just a few Caspian Terns around to compliment the lone gull as potential targets, I suspect this poor bird was exhausted and starved.  And likely doomed.

Then there was the American Oystercatcher that Steve Shultz stumbled upon. I didn’t bother to try phone-scoping this one, but it is apparently only the third record for the North Carolina piedmont.
American Oystercatcher
This picture is actually from Carteret County; I just figured I should include an Oystercatcher photo.  

All these trips to Falls Lake have kept me out of the woods hunting for warblers and other migrant passerines, which have been moving through in decent numbers over the past week. This is a bit of a tragedy since some really great birds have been turning up in the triangle, such as Yellow-bellied Flycatcher, Wilson’s Warbler and Philadelphia Vireo, to name a few.

A silver lining to missing out on warblers was a large swallow flock at Ellerbe Creek that yielded my first Bank Swallow for North Carolina (#276).

Another was the gorgeous pair of American Avocets that has been be hanging around pools near the mouth of Ellerbe Creek.
American Avocet with prey
I had seen avocets before at Pea Island National Wildlife Refuge at the coast, but never this close and never doing their characteristic sweep feeding!
Check out the video!

Oh and I had promised a photo of a confusing fall warbler.  Check out this one I saw at Ellerbe Creek. 
Confusing fall warbler!
What warbler shows a white eye ring, yellow lores, bold white wing bars and a bright yellow chest?

None of the warblers in my Sibley do.  A creative combination of different plumages of Pine Warbler could fit the description, but Pines don't generally hang out in low willow trees with Common Yellowthroats.  There also were no pine trees in the vicinity. 

Anyone have a suggestion?

What a silly ending to a post about not seeing warblers.  Even when I see them it's not like I can identify them anyway! =P

Tuesday, September 13, 2011

Fall SWAMP count with SAWS

A whopping 14 masters students woke up early last Saturday morning and came out to tag along for a bird count with me in the Duke University Wetland Center (DUWC) Stream and Wetland Assessment and Management Park (SWAMP).  This shows that bird watching is exploding in popularity!  That, or that graduate students will do just about anything for free donuts and coffee, which were graciously provided by the Student Association of Wetland Scientists (SAWS) Duke Chapter.  But probably the real draw was celebrity leader Jeff Pippen who took time out of his busy schedule of finding rare seabirds in Durham to educate us all about everything natural that was to be found.
Jeff Pippen distilling wisdom in SWAMP

The Al Buehler fitness trail runs right through the SWAMP site and gets lots of traffic.  During our count we happened to be sharing space with an actual collegiate cross-country meet.  Obviously this isn’t the most conducive setting for birds and birding and we weren’t able to find any exciting fall migrants. 
A Belted Kingfisher at the pond was a crowd-pleaser.  But the best wetland bird came after everyone had left and I stole off on my own to count one final section of the site that is inaccessible to the public.  At a small vernal pool I stumbled upon a very agitated Green Heron that kept flaring its crown feathers, croaking and flicking its tail.
Green Heron
Here's a video of the tail-flicking part:

I was happy to see the Green Heron, but I think it was upset I hadn’t brought the others.  Even if the birds weren’t spectacular, it was a gorgeous morning and nice to show the restoration areas and new board walks and platforms to the group.  For me it was also more data for my bird study and I learned some new wetland plant species from Jeff.

Check out that Dodo!
 A big thanks to Jeff and all the SAWS participants for making such a great day!