Date: 6/29/18 1:14 pm From: Steve Walter <swalter15...> Subject: RE: [nysbirds-l] Roseate Tern Banding and Aging Follow Up
Thanks, Bob. I started wondering about the number that were banded. Actually, it’s 2016 that I’m wondering about, given the wide range in the codes on the bands. And I don’t expect the 2017 birds to be here until next year.
I received the information on J03 and J76. As I expected, they were banded as chicks in 2016. The certificate actually gives “New York, USA” as the banding location, but we know it’s Great Gull Island. I guess New York has more meaning, should the birds be sighted on the wintering grounds or whatever.
This is actually getting interesting, so I went out today to see what’s next. Today at Nickerson, there were 3 Roseates – banded birds H99 and J14, along with an unbanded one (yeah, one for the photographer side of me). All were in full adult plumage. So that makes 8 different individuals in my last three trips. Shai has told us of the daily turnover in Arctic Tern individuals, based on close examination of plumages. It’s so much easier with bands on the Roseates – and it’s looking like constant turnover in them, as well.
Granted, it’s a small sample size, covering only the second half of June (when I started noticing the blue bands). But I’m starting to see a picture emerging that shows the loafing Roseate Terns on Long Island as nomadic two year olds. And most of them look like adults, which we wouldn’t suspect as two years olds without the bands. If in fact that turns out to be the case, it could be expected that the number of loafing Roseates that are found correlates to the breeding success two years earlier. Of course, more people looking helps. And I should point out that patience helps. Pat Aiken and I staked out the area in front of the east Common tern colony for much of the morning. It was maybe an hour in (for me) that J14 arrived, and another hour or so until H99 and the unbanded one showed up.
One last thing for now. Why did I only begin noticing the blue bands last week? I went back and checked my whole picture collection. Historically, the bands have been metallic – which are nearly unreadable in the field. So I focused on finding unbanded birds for pretty pictures. But it turns out that I photographed two birds with blue bands last year. One was at Nickerson – in the fenced off, sometimes wet, area. That puts some distance between you and the bird. And a dark blue band, with light reflecting off it, can look silvery. The second one was at Cupsogue, with the band partially immersed in water. In contrast, the loafing terns at Nickerson this year have been mostly on the beach, where they’re front and center, and the bands are noticeable and readable. I might yet be able to decipher last year’s band codes. I do know that both begin with “R”, so that should tell something – which I expect will turn out to be 2015 hatchlings. Enough for now.
From: Robert Paxton [mailto:<rop1...>]
Sent: Friday, June 29, 2018 2:20 AM
To: Long Island Birding <michaelzito...>
Cc: Steve Walter <swalter15...>; NYSBIRDS <NYSBIRDS-L...>
Subject: Re: [nysbirds-l] Roseate Tern Banding and Aging Follow Up
More Roseate Terns than usual are being reported this summer at Breezy Point, Nickerson Beach etc. Some observers may not be aware that Roseate Terns have traditionally bred widely (though sparingly) along the south shore of Long Island. The only big colony is on Great Gull Island, off the east end (1600 chicks were banded there in summer 2017 by Helen Hays' team). The next biggest colony used to be several hundred pairs at Cedar Beach, but that colony was spooked by a fox a decade or so ago and has not reformed. Since then, there are at best only a very few small colonies at places like islands in Shinnecock Inlet. Maybe there's an upswing this year, but Roseate Terns are not unexpected as a breeding species in small numbers anywhere on the south shore. Knowledge of current breeding locations is poor, so if anyone finds breeding activity this summer that information (maybe not announced for a month or so to avoid disturbance) would help conservation efforts. We are at their southern limit (they don't breed at all in New Jersey).
Thanks for the update Steve, of note a few days ago I observed two of the roseates at Nickerson displaying courtship behavior. I tried to get it on video, but they stopped before I could start filming. Maybe some are breeding? Or practice? Also of note, some birders observed last year there was a roseate that bred with a common tern but the nest was unsuccessful. Thoughts anyone?
After submitting last week’s Nickerson Beach Roseate Tern bands, I got back the official information today. There’s a correction to the preliminary info. It turns out both birds were banded as chicks two years ago. So that “second summer type” bird (Y11) is indeed two years old, not three as previously reported. In fact, the actual banding date was June 26, 2016 – two years ago today. So I thought it was important to pass that along. With all the people now studying terns, I don’t want misleading information out there.
Not that there can’t be older birds with incomplete adult plumage, but I’m getting the sense that it’s more likely to find two year old birds in full adult plumage (but not breeding yet). I say this because today there were two more adult birds, again with blue bands (J03 and J76). Since this is the first year that I’m seeing these kinds of bands, I’m going to assume – until I definitively find out otherwise – that such banding began two years ago. So I’m assuming today’s birds are two year olds that are roaming around (as opposed to birds that should be on the breeding grounds, providing new chicks for blue bands to be placed on).
There was also a “second summer type” plumaged Roseate, with more extensive white on the forehead than Y11. At first I thought of the possibility of a first summer type. But a closer look at the rest of the bird dissuaded me on that. This one is not banded, so I won’t know for sure from banding data. But I will get to enjoy untainted pictures of a different looking Roseate than I’ve gotten before. I’ve added one picture to the bottom of my Recent Work page, along with the 5 Common Eiders that I think were previously reported. No picture of the male Surf Scoter or the Bottle-nosed Dolphins (even though I think I actually got enough of one to get its eye out of the water).