Tripper and all,

This is indeed a first-summer Arctic Tern, a long-anticipated first for Breezy 
Point. This record illustrates three things that need emphasis: the variability 
of this species and the relative importance of the many subtle characters; the 
difficulty of identifying this species confidently--and ongoing requirement for 
thorough documentation for the acceptance of any report on Long Island; and the 
species’ peculiar, probably unique, mode of occurrence on Long Island, wherein 
the records are more numerous than in other “rare” species, can be expected to 
occur in the appropriate highly stereotyped context around any ocean inlet, 
from Rockaway to Sagaponack, but individual occurrences are nevertheless 
basically unchaseable.

As you note, its structure differs less strongly from that of Common Tern than 
those of many Arctic Terns. Both its bill and its legs are larger than those of 
other recently well-documented individuals, and its overall plumage appearance 
is also different from the assortment of adult-like, advanced second-summer 
type, delayed second-summer type, and first-summer individuals recently 
observed, documented, discussed, and debated. Furthermore, as is often the 
case, the impression given by this bird varies greatly from image to image. In 
brief, images ML104255381 and ML104255391 are perhaps the most unambiguous, 
showing the overall structure (short bill, short neck, long hands, long tail), 
head pattern (white forecrown extending further back on the head and forward 
part of face mask triangular and encompassing the eye), and primary pattern 
(dark tips of individual feathers smaller than on Common Tern) conveniently. In 
contrast, I’m guessing that image ML104255361 is causing a lot of confusion, as 
the bill and legs look long and the head pattern looks too much unlike those on 
some of the motley first-summer Common Terns we’ve been seeing lately. But if 
the bird is an Arctic Tern an image of this quality should be diagnostic, and 
it is. The length of the primary projection (the blade of folded feathers 
extending from the tertials) is longer relative to the overall size of the body 
than in Common Tern. Furthermore, one can assess accurately the length of the 
black tip to the outermost primary on the far wing: it hooks back on the inner 
web for just a short distance, perhaps a centimeter or so (in the field, 
measure this against the leg and bill, allowing for what you know about their 
absolute lengths). This feature can be hard to see in individual photos, but it 
is often readily assessed in the field. Compare the adult and left-hand 
first-summer Common Terns in image ML104255291: the black on p10 extends more 
than twice as far along the tip of the inner web. Another point is the color of 
the legs, a vinaceous, dusky-maroon tone unexpected on first-summer Common 
Tern. In sum, the structural points reign supreme but are variable and require 
a lot of familiarity; ditto for the head pattern (and covert patterning and 
other aspects of body plumage), except that here the variability is even more 
complicated; the primary pattern is diagnostic, unequivocal when assessed 
properly, and unvarying among age groups in both species. The only downside 
with this last feature is that it can be difficult to assess properly from 
individual images, because of angle, parallax, lighting, etc.

The second point is that this species is difficult to identify and still 
requires thorough documentation. Every June in recent years I have received 
photos of prospective Arctic Terns from many, many people, many of whom are 
highly skilled, careful, and experienced birders. It is remarkable how low the 
correlation has been between the observers’ initial confidence and the subject 
birds’ identities: many of the genuine Arctics thus revealed were reported as, 
“I think this is just a Common Tern, but…” whereas a large percentage of the 
birds strongly hoped for as Arctics were actually Commons. I suspect that more 
than a few people viewing Tripper’s images were not completely sure about the 
identification. Ask yourself honestly, did you think this was a Common Tern? If 
not, were you completely sure this was an Arctic Tern? I strongly suspect that 
only a very small handful of people confidently knew the answer, understood 
why, and would be able to explain it. If so many of our best birders are 
unsure, even given this long series of high quality images, then how can we 
trust sight records, which nowadays usually imply poor, distant, and brief 
views?

Thirdly, this record, along with Tripper’s discovery earlier this spring of an 
adult Arctic Tern at Plum Beach, should establish definitively that this 
species occurs in its intriguing, almost inscrutable fashion, at ocean inlets 
all along the outer coast of Long Island. The first five Arctic Terns I found 
on Long Island were at Democrat Point, Fire Island Inlet, in 1999-2000. I 
didn’t find another one until I resorted to tern therapy to calm myself while 
baby-sitting Ken and Sue’s Bar-tailed Godwit at Mecox Bay in 2004. All of these 
records were genuinely a big deal at the time. It was not until 2005 that Pat 
and I found the first one at Moriches Inlet, precipitating the now-familiar 
cottage industry of tern ogling, phone dunking, and margarita guzzling there. 
Earlier, P. A. Buckley had found them on the inaccessible bars at Shinnecock 
Inlet, and eventually we managed a couple from that area, too. Later, Donna 
Schulman, John Shemilt, and others proved that the early Mecox bird was not a 
fluke by finding several there. Far to the west, Nickerson Beach has produced 
the steadiest stream of records over the last five years or so, owing in part 
to its accessibility and the off the charts concentration of camera attention. 
More recently, proving the point in an elegant scientific experiment, Derek 
Rogers has found Arctic Terns at Long Island’s newest inlet, Old Inlet, which 
re-breached after Sandy. Lastly, we have Tripper’s two records from Rockway 
Inlet already this year. To my eye, there is no peculiar concentration of 
records at Moriches Inlet, just a prolonged period of good conditions and 
thorough and competent coverage. As the precise positions favored by loafing 
flocks of non-breeding terns shift around, and as observers become more 
numerous and more familiar with this species, we will surely continue to see 
more and more records from a variety of sites—but we will only understand this 
based on well-documented reports.

Shai Mitra
Bay Shore

________________________________________
From: bounce-122635039-11143...@list.cornell.edu 
[bounce-122635039-11143...@list.cornell.edu] on behalf of peter paul 
[pep...@gmail.com]
Sent: Wednesday, June 13, 2018 5:14 AM
To: nysbirds-l; Ebird NYC
Subject: [nysbirds-l] Breezy Point Queens

Last evening I had a possible Arctic Tern at Breezy point in Queens.  The jury 
is still out, and thoughts would be welcome.  Images of the bird can be seen 
below in my ebird report, and from flickr. The bird stuck around for about 6 
minutes before flying off, and I was unable to refind it (though I didn't stay 
terribly long looking).  Winds were strong from the SSE, and terns were 
constantly rotating though - there were at least four first summer COTEs and 
one second summer bird over the course of my observation.  Details here:

https://ebird.org/view/checklist/S46510785

https://www.flickr.com/photos/129132563@N05/ and

Happy terning,
Tripper


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