Hi Tim and all, There are a number of parallel systems for denoting age. The worst for birders is the plumage cycle system, because at this time of year a flock of 30 manky looking Lesser Black-backed Gulls of exactly the same age 350-370 days since hatching might include both first and second cycle individuals, and it's obviously absurd to lump the former with fresh juvs and the latter with two year-olds in summaries of age break-downs.
My preferred system for terns is the standard one used by Grant, Malling Olsen, and others: Juvenile the newly hatched COTE juvs are the cutest of all birds First-summer one-year-old birds with black bills, white foreheads, white underparts, short tails, etc. Second-summer types a category including some (but not all) actual two year-olds and a fraction of older adults failing to attain full breeding condition. The appearance of birds in this category is highly variable because it includes some very delayed two year-olds as well as some birds that barely differ from normal adults. Adult Calendar year notation works well too in the temperate zone: HY SY TY type Adult Best, Shai ________________________________________ From: [email protected] [[email protected]] on behalf of Timothy Healy [[email protected]] Sent: Monday, June 18, 2018 6:48 PM To: Steve Walter Cc: NYSBIRDS 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 <[email protected]<mailto:[email protected]>> 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/[email protected]/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/[email protected]/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/[email protected]/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/ --
