Friday, August 29, 2008

An Old World Dunlin, and hybrid

While birding South Beach, MA on Friday the 22nd, I came across two interesting calidris sandpipers that were feeding on the incoming tide in the same general area.

The first bird was a small alternate-plumaged Dunlin that immediately caught my eye. Especially after having just seen a couple of typical hudsonia Dunlin, this bird’s small size and short bill were striking. In addition to the size and structure, a few other things stood out as well. It’s scapulars seemed to lack any trace of red. Instead they showed a golden-buff. The bird’s face was also decidedly brownish and not very pale, and the upper breast was very heavily streaked, nearly all the way down to the upper border of the black belly patch. It had a dark-headed and dark-breasted look…obviously darker than your typical hudsonia.

I caught up with a group of birders and got them on the Dunlin, which we watched for quite some time. One of them mentioned that the bird almost had a Least Sandpiper feel/giss to it, which I thought was an interesting observation. This sort of impression was likely due to the bird’s small size, short down-curved bill, short-ish legs, and brownish upperparts/head/upper breast.

I’m having some trouble finding in-depth coverage of separation of the Old World Dunlin subspecies, but this bird seems to match C. a. arctica in many respects. I have zero experience with arctica and schinzii, so any comments from experienced observers would be especially welcome.

Interestingly, a small-billed Dunlin has been seen for three summers now at South Beach. In 2006 Blair Nikula photographed a first-summer bird, photos HERE.
Last summer, Marshall Iliff found an alternate-plumaged arctica Dunlin here. Could this be the same bird 3 years in a row?

Here are some photos including a couple showing size comparison. It appeared to be the same size as Sanderling in the field, and this shows up in the photos as well. The images have not been altered in any way other than being cropped (no sharpening, no color alterations, etc). Click them for larger views.
















For additional, larger images click HERE. I can send originals on request.

The other interesting bird was one of the two presumed hybrids photographed by Cameron Cox, Blair Nikula and others over the past two summers. There has been a rash of sightings of similar birds in the eastern US recently, proposed as potential White-rumpedXDunlin hybrids.

I snapped some photos of that bird, which are posted below. I cannot currently offer a better suggestion than probable White-rumpedXDunlin, but the complete lack of a black belly patch in all of these similar eastern US birds makes me scratch my head a bit. In flight, the uppertail showed a diffuse line up its center, as if intermediate between White-rumped Sandpiper and a dark-rumped bird.













HERE is a link to Blair’s fantastic set of images from earlier this summer.

Nick

Monday, August 25, 2008

8/22 - South Beach

Here are some other images from South Beach on Friday. 21 species of shorebird were tallied on the day. I didn’t stumble across anything rare (except maybe a certain Dunlin subspecies and a hybrid, which I'll post in the coming days), but it was a spectacular afternoon to be out there. The temp was perfect, a slight breeze blowing, and the visibility was fantastic. I couldn’t tear myself away in time to catch the last ferry back, so I ended up walking instead. It was worth it, as thousands of shorebirds came in to roost.


A small portion of a large mixed flock


Western Sandpiper (center)


American Golden-Plover


Whimbrel


White-rumped Sandpiper


White-rumped Sandpiper


From front to back: Black, Common, Roseate, Roseate



One of 23 Hudsonian Godwits






One of three Marbled Godwits


A mixed flock of godwits, yellowlegs, and more.

NB

BBC Pelagic #3 - Hyannis to Veatch's Canyon on 8/23

The third and final deep-water BBC pelagic sailed out of Hyannis early on Saturday morning. Our target was Veatch’s Canyon. Unlike the July trip, no rarities were to be found. It was still an enjoyable day out on the water. Highlights included 3 Audubon’s Shearwaters, a Pomarine Jaeger, Red-necked Phalaropes, 2 Sperm Whales, Risso’s Dolphins, and my life Manta Ray.



Pomarine Jaeger


Red-necked Phalaropes


Manta Ray


Risso's Dolphin


Audubon's Shearwater


Audubon's taking flight
video

Wednesday, August 20, 2008

8/20 - Charlestown Breachway

Vacation started on a bit of a sour note when a pelagic trip out of Rhode Island was called-off halfway through our ride to Block Canyon. However we were able to make the most of the afternoon with a visit to the well-known Charlestown Breachway. Fifteen shorebird species were tallied, with highlights including an AMERICAN AVOCET and 8 Whimbrel, plus a single Forster's Tern.







NB

Sunday, August 10, 2008

Western Willet vs. Eastern Willet

While birding Sandy Pt on Saturday afternoon, a juvenile Western Willet was present among five or so juvenile Eastern Willets (the local adult Easterns seem to have departed). I was able to grab a few decent images of both subspecies. Separation of Western (inornatus) from Eastern (semipalmatus) Willet is something that is being attempted more and more lately, and it is very doable especially when both subspecies are present side-by-side. Someday these two subspecies may be split into full species, so it would be outstanding to get a head start on identifying every Willet we see.

Western Willet:
- longer-legged, larger size, and more lanky overall
- longer, thinner bill (especially the tip)
- paler than Eastern; juveniles appear grayish
- less contrast between scapulars and wing coverts than Eastern (does not apply to adults)


Note the long legs, size much larger than the adjacent Greater Yellowlegs, bill shape, grayish coloration, and the degree of contrast between the scaps and coverts.


A different angle of the bill


That is one big, lanky, pale willet.

Eastern Willet:
- more compact shape, averages smaller size
- thicker bill
- darker than Western; juveniles appear brownish-gray
- more noticeable contrast between darker scapulars and paler wing coverts (does not apply to adults)


This photo shows the darker/browner coloration, shorter stature (but tough to see with all that vegetation), and thicker bill.


Here you can get a feel for the bird's smaller size as compared to a Greater Yellowlegs; it is just a bit larger than the GRYE. You can also appreciate the greater contrast between scaps and coverts.


A different angle of the bill, and another view of the darker scapulars and how they contrast more with the paler wing coverts.

If I can get more/better images of these willets in the coming days, I will update this post.

Good shorebirding,
Nick