Shai does an excellent job summarizing the complications of the terms. And he makes a very important point about using the term “type” since there is so much individual variation you cannot always reliably join plumage to chronological age. I would disagree with one point however. On Great Gull Island we trap numbers of Common Terns that are 20 years old or older. (I frequently tell students the bird they are handling might be older than they are.) Some seasons we may handle a hundred birds in this age bracket. It is highly unusual for them to be visually different from from other adults, so I would disagree with Shai’s statement that many Common Terns in this age bracket look like TY birds. I should note that we are trapping birds on nests with hatched chicks so they are generally in healthy breeding condition. It is certainly possible that birds in subprime condition may not be in full adult plumage.
Joe DiCostanzo Sent from my iPad > On Jun 18, 2018, at 8:01 PM, Shaibal Mitra <shaibal.mi...@csi.cuny.edu> wrote: > > Tim, > > There's an error here. > > Regardless of what's true of any given bird, note the following > equivalenciesduring June-July in NYS: > > Juvenile = HY = hatching-year > First-summer = SY = Second calendar year > Second-summer = TY = Third calendar year (but caveat: many this age look like > adults, and some adults look like this, hence "type") > Adult = ATY = After Third calendar year. > > With terns: > > 1. the first-summer plumage (=SY =second calendar year) is usually highly > stereotyped; this is the "portlandica" plumage; one year-old birds that > differ obviously and consistently from breeding adults. > > 2. the second-summer type plumage (associated with but not identical to TY = > third calendar year) is highly variable. Part of this arises because it > comprises some actual TY birds (two years old; but note, many TY birds attain > definitive adult appearance), and also a percentage of older, fully adult > birds that are not in prime condition (very old Common Terns >20 years old > often look like this). > > Below are links to a series of second-summer type Arctic Tern individuals, > spanning the gamut from very delayed (almost portlandica-looking) to nearly > adult looking. The Arctic Terns that show up on LI are non-breeders, and they > range from classic first-summers through all manner of second-summer types to > almost adult-looking birds. But among the latter, they almost always show > some defect from full breeding adult condition, and these occur all through > June and early July. Thus I tend to suspect them as mainly seond-summer = TY > = Third year = two year-olds. > > https://flic.kr/p/VVHtaZ > https://flic.kr/p/VhQ65U > https://flic.kr/p/VT2po6 > https://flic.kr/p/VCjr6C > https://flic.kr/p/VPwvqd > https://flic.kr/p/VT2pRk > https://flic.kr/p/VCjq6G > https://flic.kr/p/VT2rrp > https://flic.kr/p/VT2otk > https://flic.kr/p/VhQ6fo > > Best, > Shai > > > ________________________________________ > From: bounce-122646499-3714...@list.cornell.edu > [bounce-122646499-3714...@list.cornell.edu] on behalf of Timothy Healy > [tp...@cornell.edu] > Sent: Monday, June 18, 2018 7:28 PM > To: Steve Walter > Cc: NYSBIRDS > Subject: Re: [nysbirds-l] Nickerson Beach Arctic Tern and others > > This is where many banders and field biologists often use the abbreviations > SY and ASY, for second year and after second year. The second year, a.k.a. > second summer a.k.a. year old, plumages for many species are pretty > definitive, and quite distinct from adults. In the case of COTE and ARTE, > birds stay in a plumage that resembles their initial juvenile coloration for > their second calendar year. The black-billed, white-foreheaded birds that are > so abundant at the beach this season are coming up on a year old. This > “imperfect” adult Arctic, with only some smudges, flecks, and short streamers > to separate it from a classic mature bird, is probably at least two years > old. I certainly don’t think it was born during the last season, which is > what I understand makes a second summer bird. It may be in its third summer, > or maybe it’s older and just a little funky. I reported it on eBird as ASY, > because it is definitely far more progressed than the typical yearling birds > loafing around the inlets. > > Cheers! > -Tim H > > On Jun 18, 2018, at 7:15 PM, Steve Walter > <swalte...@verizon.net<mailto:swalte...@verizon.net>> wrote: > > Tim, > > In normal conversation, I typically use the phrase “two year old” for birds > that I suspect were born two summers ago. But as the conversation of recent > days has alluded, there can be adults that for whatever reason, are not > complete. And adult traits may not develop in sync in younger birds. Looking > back at the weekend’s posts, I saw that Pat Lindsay made a point about her > “second summer type” having a black bill. Today’s had a red bill. So a two > year old? Probably. But definitely? Maybe, maybe not. It looks like it – so > “second summer type” works for the public record. > > Steve > > > From: Timothy Healy [mailto:tp...@cornell.edu] > Sent: Monday, June 18, 2018 6:49 PM > To: Steve Walter <swalte...@verizon.net<mailto:swalte...@verizon.net>> > Cc: NYSBIRDS <nysbird...@list.cornell.edu<mailto:nysbird...@list.cornell.edu>> > Subject: Re: [nysbirds-l] Nickerson Beach Arctic Tern and others > > Steve and other sternid enthusiasts, > > Isn’t second summer the term used for the immature aspect birds with white > foreheads and black bills? A freshly fledged juvenile would be living through > its first summer, so second summer individuals are yearlings, correct? If my > understanding of the nomenclature is accurate, the bird I found yesterday, > which matches Steve’s description and the photos of Tripper’s bird from > Friday, would be in its third summer or older. At a glance it looks like a > classic alternate plumage adult ARTE, but the faint darker smudging on the > carpal bar and the tail streamers that don’t extend beyond the folded > wingtips indicate that it is not fully mature. I saw a similarly marked > individual at Nickerson last year, and in 2015 I got a photo of an adult-like > ARTE with a surprisingly dark bill. The variation in age classes and species > of terns is so fascinating. I’ve learned a lot from these discussions about > Arctics, Roseates, and the mysterious dark Commons. Mornings and afternoons > at the colonies and inlets are one of my favorite parts of early summer here > on Long Island. > > Cheers! > -Tim H > > On Jun 18, 2018, at 6:05 PM, Steve Walter > <swalte...@verizon.net<mailto:swalte...@verizon.net>> wrote: > Another day, another Arctic Tern at Nickerson Beach. Actually, my first for > the year, and this one had to be waited on. It might have been too foggy in > the morning for it to find land (joke). Interesting bird this one. My tern > guru advises me to call it a “second summer type”. Basically adult looking > with a red bill, but with a carpal bar and speckling on the forehead (not > well visible in the picture I posted). In a similar vein, there was a Roseate > Tern of less than full adult appearance. This bird, and also a full adult, > had readable blue legs bands. Maybe others have seen this, but this is the > first time I’ve seen terns with something more readable in the field than the > metal bands. I’ll reports these (bands B97 and Y11) and find out more in due > time. But perhaps someone on this list might know something (Joe D?). Also, > a Gull-billed Tern flying over the east tern colony around mid-day. Pictures > of the Arctic and Roseates have been added to the bottom of the Recent Work > page at my web site http://stevewalternature.com/ . > > Steve Walter > Bayside, NY > -- > NYSbirds-L List Info: > Welcome and Basics<http://www.northeastbirding.com/NYSbirdsWELCOME.htm> > Rules and Information<http://www.northeastbirding.com/NYSbirdsRULES.htm> > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NYSbirdsSubscribeConfigurationLeave.htm> > Archives: > The Mail > Archive<http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html> > Surfbirds<http://www.surfbirds.com/birdingmail/Group/NYSBirds-L> > ABA<http://birding.aba.org/maillist/NY01> > Please submit your observations to eBird<http://ebird.org/content/ebird/>! > -- > -- > NYSbirds-L List Info: > Welcome and Basics<http://www.northeastbirding.com/NYSbirdsWELCOME.htm> > Rules and Information<http://www.northeastbirding.com/NYSbirdsRULES.htm> > Subscribe, Configuration and > Leave<http://www.northeastbirding.com/NYSbirdsSubscribeConfigurationLeave.htm> > Archives: > The Mail > Archive<http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html> > Surfbirds<http://www.surfbirds.com/birdingmail/Group/NYSBirds-L> > ABA<http://birding.aba.org/maillist/NY01> > Please submit your observations to eBird<http://ebird.org/content/ebird/>! > -- > > -- > > NYSbirds-L List Info: > http://www.NortheastBirding.com/NYSbirdsWELCOME.htm > http://www.NortheastBirding.com/NYSbirdsRULES.htm > http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm > > ARCHIVES: > 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html > 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L > 3) http://birding.aba.org/maillist/NY01 > > Please submit your observations to eBird: > http://ebird.org/content/ebird/ > > -- > -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME.htm http://www.NortheastBirding.com/NYSbirdsRULES.htm http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birding.aba.org/maillist/NY01 Please submit your observations to eBird: http://ebird.org/content/ebird/ --
