Monday, March 20, 2017

*Happy Mew Gull Day 2017!* - Kamchatka Gull and Thayer's-type thing

Happy Mew Gull Day, everybody. My new favorite holiday, just edging out Festivus.

I realized last year, after a two Mew Gull day, that all three Mews I had found in CT happened to fall on March 20th. Weird. So this year I made a point of gulling on the same date. Fully aware that I was introducing observer bias,  I was still shocked when one appeared. And the kicker - of those four March 20th birds, three subspecies have been involved (two canus, one brachy, one Kam). I didn't look any harder for Mew Gull today than I do on any other gull excursion, of which there are many at this time of year...yet today was still the day I ran into one. Pretty great coincidence.

I actually think this might be the same Kamchatka Gull from April 2015 (which, as it turns out thanks to photo review, had been seen on Nantucket earlier that winter and likely the winter before too! So cool to track vagrants like that.). At first glance it looks pretty identical overall, except that it lacks the pinhole mirror on its left p9 and has a paler iris. These are things that could change with age, one would assume. I'll have to take a closer comparison look later.

This flock wasn't particularly large - just a few hundred birds or so that were filtering in from feeding offshore, presumably on surface plankton as they do this time of year. These plankton-seeking flocks are very mobile. The bird, along with a few of the Ring-bills, took off down the beach and around the corner. Despite alerting local birders immediately, nobody was able to relocate it.

The lighting conditions this morning at Russian Beach in Stratford, CT were brutal. Everything was either backlit or side-lit with bright sunlight. You will not see any pretty pictures here. Judging shades of gray via photo will be even harder than in the field, and it was no picnic in the field either. The slightest change in angle relative to the sun made such difference. I made a point to not correct anything in the images below, unless noted in the caption.

Just before the Kam Gull I had an adult dark-winged Thayer's-type.  Not sure where to draw the line on adults of these birds (however they are related...). Comments welcome as always. There are images further down. First, the Kam.

Overexposed a bit. Darkness of saddle was washed out by the harsh sunlight -it stood out like a sore thumb from the RBGU on mantle shade alone. Tertial crescent really popped. Bill bright yellow and unmarked. Legs bright yellow. Iris was brown and clearly contrasted with pupil with scope views. Coarse streaking to head and neck that extended onto and across breast; breast markings were distinct (as opposed to the smudgy wash of brachyrhynchus)  and had a horizontal blotchy and barred look to them. Forehead slopes into somewhat strong (but not monstrous) bill for a Mew, imparting a snouty look. Body not slim or petite as you would expect in canus or brachyrhynchus.

Gives some idea of the heaviness and blotchiness of the neck and breast streaking. Bird seen head-on briefly in scope, as it shuffled on a rock, to study quality and extent of breast markings but not photographed in that pose.




Note how the broad secondary trailing edge narrows at the inner primaries, a feature of the three Eurasian Mew Gull subspecies

Subject bird at upper left. Best I could do via photo with comparing upperpart shade to RBGU.

Subject bird at center, with RBGUs in frame for comparison

Wish I had gotten more representative (AKA better) photos, but I think the salient features are still obvious, except for the center of the breast. This bird checked the big Kam Gull boxes nicely, though they do get more monstrous and larger-billed than this. Perhaps a female. In brief, heinei in this plumage would show a flat crown and a very white head with pencil-thin streaks across the hindneck, per the excellent Dutch Birding article by Adriaens & Gibbins. That form can be ruled out. Canus and brachyrhynchus ruled out pretty easily as well on a suite of structural and plumage features.

Since you're here, how about this harder one? Thayeri or kumlieni? I go back and forth on how we should treat this identification, and at this moment I'm not feeling strongly either way about birds like this. I might put more thought into this right now if not for it hardly being the bird of the day.

Subject bird at left. Direct sunlight on folded primaries and it still was very dark. Next to adult HERG.

Pale amber eye


Shadows lightened in this photo; more for structure and coarse pattern of head/neck/breast markings than anything

Shadows lightened in this photo; more for structure and coarse pattern of head/neck/breast markings than anything

Upperwing:
right

left

Underwing:
right

I don't think I'd go so far as calling the primaries matte black from above - I think a very dark gray would be more accurate(?). Again, tough with the complete lack of neutral lighting conditions. A good Thayer's, if such a thing exists, or no?

 - Nick

Saturday, March 18, 2017

Barrow's Goldeneye - Madison, CT

A drake BARROW'S GOLDENEYE is wintering in the Tuxis Island, Madison area for the third year in a row. Yesterday I finally went to take a look for the first time this winter. After scanning offshore from two vantage points and not seeing it, we found the bird very close to shore while driving the coastal road. A treat to see this locally scarce species so well.


Barrow's Goldeneye
 - NB

Thursday, March 16, 2017

CTYBC Gull Trip

On Sunday March 12th four very hardy and intrepid members of the Connecticut Young Birders Club joined me for a full day of gulling along the Connecticut coast. We should be approaching peak gull diversity over the next few weeks thanks to the annual late winter/early spring Long Island Sound plankton bloom, an event I've mentioned so many times here. During the first two weeks of this year's event numbers have been building but diversity has been very slow to follow. This is often the case during the first half of March. Diversity usually peaks, I'd say, between March 20 and April 10 or thereabouts. So far this season Lesser Black-backed Gulls have yet to make any migratory push through the region as only the known wintering adults have been reported, and all white-winged gulls have been unusually hard to come by. It seemed to be a down winter for first cycle Iceland Gulls in CT, so perhaps that shouldn't be of much surprise.

Anyway, on this day the weather felt more like January than March. While we didn't have to deal with any snow (this was the calm before the blizzard), temps were cold and a brisk wind did not help. That didn't keep us from a really interesting day of gull study.

In the end we recorded six gull species on this day. In addition to the three guaranteed species (Herring, Ring-billed, and Great Black-backed), we had two Bonaparte's Gulls (these should become much more numerous in a matter of days), four Iceland Gulls, and one Lesser Black-backed Gull.

Adult "Kumlien's" Iceland Gull at Seaside Park in Bridgeport:


with Herring Gull



Iceland Gull

Adult Lesser Black-backed Gull at Burying Hill Beach in Westport:


Lesser Black-backed Gull

We also had two very interesting Ring-billed Gulls - one young bird with a Common Gull-like feel to it, and one "white-winged" adult with very little black in the primaries.

First, the Common Gull mimic. This bird stood out among a flock of ~500 Ring-bills by its tiny bill, more rounded head, slight frame and thin legs. We studied this bird for a while, and I really struggled with it. The flock left the beach to feed offshore and we never did see or photograph it in flight. Despite the structural similarity to "Common" Mew Gull, I really think that this was just a runt Ring-billed Gull. While not terribly apparent in the photos, the incoming scaps were every bit as pale as on the surrounding Ring-bills, and most were fringed in white. These two features are pro-RBGU and I think are key on this bird that was otherwise lacking in plumage clues. The wing coverts were rather worn/faded and of little help, and we never got a look at tail pattern. I'm happy to receive comments on these photos.




We spotted this adult Ringer and noticed that it had a huge amount of white to the folded wingtip. Flight views of the wing were impressive.

at right




"white-winged" Ring-billed Gull

Toward the end of the day we found ourselves at Southport Beach in Fairfield, well-known low tide gull roost, especially for Bonaparte's Gull flocks as April approaches. While there weren't many gulls on this day, young birder Aidan Kiley had found a PINK-FOOTED GOOSE here the day before. It was still there when we arrived. A nice way to wrap up the day!



Pink-footed Goose
young birders photographing LBBG

  - Nick