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14 Apr Least Tern, Cayuga Lake, New York [Angus Wilson ] 11 Apr Re: article on European vagrancy [] 11 Apr article on European vagrancy ["Thomas B. Johnson" ] 4 Feb Re: Web archiving on Birdingonthe.net coming soon... [Rick Wright ] 4 Feb Re: Web archiving on Birdingonthe.net coming soon... ["Rick Wright" ] Subject: Least Tern, Cayuga Lake, New York From: Angus Wilson <gadflypetrel AT hotmail.com> Date: Mon, 14 Apr 2008 14:26:14 -0700 (PDT) On Saturday (12 April) several observers reported a probable LEAST TERN from Mud Lock at the northern end of Cayuga Lake in central NY. Bob McGuire and Susan Danskin studied the bird at a distance with 4 Common Terns for comparison. It was relocated later in the afternoon by Paul Hurtado and his friend Deena who concurred with the identification. Unfortunately no photographs were taken and I've not heard of any subsequent sightings. Although Least Tern is a common summer breeder in coastal New York, principally Long Island, this is a major rarity elsewhere in the state. The early date is also notable as I have not heard of any coastal reports yet. Common Terns seem to infiltrate into western NY earlier than coastal sites and perhaps this Least Tern followed a similar route? This got me thinking about the routes used by waterbirds such as terns (Caspian, Common and Black) during their spring migration to inland nesting sites in New York state? Do they filter east from the Mississippi Flyway following the lake shores or follow river systems (presumably at altitude) out from the Susquehanna and Delaware watersheds? Angus Wilson New York City/Springs http://www.oceanwanderers.com http://oceanwanderersnews.blogspot.com/ http://oceanwanderersbooks.blogspot.com/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "North American Bird Distribution" group. To post to this group, send email to NABirdDist AT googlegroups.com To unsubscribe from this group, send email to NABirdDist-unsubscribe AT googlegroups.com For more options, visit this group at http://groups.google.com/group/NABirdDist?hl=en -~----------~----~----~----~------~----~------~--~---Subject: Re: article on European vagrancy From: sgmlod AT aol.com Date: Fri, 11 Apr 2008 16:17:08 -0400 Thanks Tom The synopsis of the research paper presented at the above link is interesting. If it accurately portrays the study discussed, a strong bias may have been present in the study. The distance traveled by the species studied was fixed because these species all have a similar breeding range and all vagrant records were?from central Europe. If these sepcies happened to have a similar winter range, which could easily happen for a variety of non-independent reasons, then you'd find exactly what these authors found. But YB Warblers occur regularly (or somewhat regularly) on Iceland..... which is not the same distance from the breeding grounds as Germany, I suspect. More importantly, almost all taxa studied were?mostly detected during migration in Europe, so that their final endpoint was likely not central Europe, and the final distance flown much greater. This totally destroys the vagrancy distance = normal migration distance theory proposed. Of course, it is hard to say this confidentally w/o seeing the study itself. Since distance and direction seem genetically programmed, one might assume that either or both factors might go awry due to mutation or disease. There have been studies to show that popultion tends to be proportional to number of vagrants. We've all seen that species w/ and expanding population tend to also have an increasing rate of long-distance vagrancy, but more to the point, Veit in the Auk showed that species showed more vagrancy in the autumn after good years of reproduction. Therefore, number of vagrants proportional to number of first year birds produced (and it is mostly first year birds making long-distance vagrancy errors). Their finding that larger population = more vagrancy when comparing different species and even genera?seems intuitive and?yet surprising, as certain genera (and perhaps species, families, etc) seem more prone to wandering (eg, Tyrannus flycatchers?-- forgive my spelling). Cheers Steven Mlodinow -----Original Message----- From: Thomas B. JohnsonSubject: article on European vagrancy From: "Thomas B. Johnson" <jaegermaster AT gmail.com> Date: Fri, 11 Apr 2008 00:10:33 -0700 (PDT) This might be of interest - I don't have the .pdf of the journal article referenced, but I'll try to track it down in the near future. http://www.sciencedaily.com/releases/2008/04/080410115420.htm Cheers, Tom Tom Johnson Ithaca, NY --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "North American Bird Distribution" group. To post to this group, send email to NABirdDist AT googlegroups.com To unsubscribe from this group, send email to NABirdDist-unsubscribe AT googlegroups.com For more options, visit this group at http://groups.google.com/group/NABirdDist?hl=en -~----------~----~----~----~------~----~------~--~---Subject: Re: Web archiving on Birdingonthe.net coming soon... From: Rick Wright <birdaz AT gmail.com> Date: Mon, 4 Feb 2008 10:20:29 -0700 That's good news, Tom! Rick On Feb 4, 2008 8:58 AM, Thomas B. JohnsonSubject: Re: Web archiving on Birdingonthe.net coming soon... From: "Rick Wright" <birdaz AT gmail.com> Date: Mon, 4 Feb 2008 10:20:29 -0700 |