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Nikon Monarch 7

    Jaeger ID

    Steve Howell, in a recent comment to The ABA Blog (click here, and scroll waaay down to the extreme bottom) posted:

    “Basically, there are two kinds of birders—those who make mistakes and those who lie about it. I haven’t misidentified a bird since the last time I went birding, yesterday, and thankfully I was corrected by a birding friend, and I learned a bit more. Hence, with the benefit of others, be they friends, peers, or BRCs, we may be led to see our mistakes and learn from them, not sulk, and [...]”

    It’s safe to say that anybody with any amount of experience with jaegers has made some mistakes. Here, then, are some tricky jaeger photos that have appeared in recent issues of Birding magazine. Of some interest is that the challenge here is Long-tailed vs. Pomarine. More commonly, it seems, the most confusing pairings involve Parasitic Jaeger: Parasitic vs. Long-tailed and Parasitic vs. Pomarine. No matter, this time it’s Long-tailed vs. Pomarine.

    Enough preamble. Here come the images, along with critical information regarding date and location. ID experts Tom Johnson and Steve Howell have already weighed in with their assessments. (Johnson: Birding, May 2012, p. 57. Howell, Birding, September 2012, p. 12.) Now what do you think?

     

    12-3-13-F03 [Quiz Bird C]
    Monterey Bay, California; 5 August. 2011. Photo by Tom Johnson.

     

    12-5-05-01 [Pomarine Jaeger]
    Off Hatteras, North Carolina; 31 May 2012. Photo by Steve N. G. Howell.

    12-5-05-02 [Pomarine Jaeger]
    Off Hatteras, North Carolina; 31 May 2008. Photo by Steve N. G. Howell.

     

    12-5-05-03 [Long-tailed Jaeger]
    Off Hatteras, North Caroliina; 11 August 2010. Photo by Steve N. G. Howell.

     

     

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    Ted Floyd

    Ted Floyd

    Ted Floyd is the Editor of Birding magazine, and he is broadly involved in other programs and initiatives of the ABA. He is the author of more than 100 magazine and journal articles, and has written four recent books, including an ABA title, the ABA Guide to Birds of Colorado. Floyd is a frequent speaker at birding festivals and state ornithological society meetings, and he has served on the boards of several nonprofit organizations. Mainly, he listens to birds at night.
    Ted Floyd

    Latest posts by Ted Floyd (see all)

    • http://wesleysbirdingblog.blogspot.com Wesley Greentree

      Are 2 and 3 Long-tailed?

    • http://scienceofbirds.blogspot.com Nick Minor

      1 and 4: Long-tailed
      2 and 3: Pomarine

    • John

      I agree with Nick.

    • Ted Floyd

      Wesley, Nick, and John: Why? Why do you think they are what you think they are?

      Thanks!

    • http://www.facebook.com/opihi Joshua S. Rose

      I came up with the same answers as John and Nick. I was going primarily by bill proportions, that the Parasitic is supposed to have a significantly longer-looking bill than the Long-tailed. Did notice the date correspondence, that 2 and 3 were both taken on May 31, 1 and 4 both in August….

    • John

      Ted, I first eliminated Parasitic from consideration because you said it was between Long-tailed and Pomarine. Moving on from that, I picked 1 and 4 as Long-tailed and 2 and 3 as Pomarine because that’s what they looked like to me. :) Actually, while I’m *trying* to be funny, that’s really the truth. If I think about it more, 1 and 4 look like Long-taileds to me because of the shorter bill and “short-headed” look they have. For 2 and 3, it’s the opposite, with long bills. Also, maybe I’m just imagining it because of the bill information predisposing me, but 2 and 3 seem to have broader wings.

    • http://profile.typepad.com/alvarojaramillo Alvaro Jaramillo

      To me the tricky one is bird 1, 2-3 look like pretty standard Pomarine based on bulk/shape, bill etc. Similarly 4 looks like a petite, narrow winged, small billed Long-tailed. Number one trips off the ID switches in my brain as a Long-tailed, not sure why. But the analytical part of my brain tells me it is a Pomarine – with that long bill, short tail and most important of all active outer primary molt in August. I would not expect to see primaries at this stage on a Long-tailed in the northern hemisphere, but I could be wrong. See also that all three (1-2-3) of the Pomarines are in molt, #4 (Long-tailed) is not. Cheers – Alvaro.

    • http://scienceofbirds.blogspot.com Nick Minor

      Ohh nice catch Alvaro!I was iffy about #1 too, and in the end I obviously leaned towards Long-tailed for the same reasons that John gave: little headed look with an overall smaller feel. But that’s totally a GIS–The length of the bill, after second thought, even when compared to #4, is considerable. The tail is a bit short too, and the molt bit totally tips the scale. After another look at Sibley, another field mark came into play here: Long-tail adults show a contrast between their paler upperwing coverts and darker secondaries, something that only #4 shows. I’m cautious though, it seems like this is heavily dependent on lighting. Nonetheless…I change my ID to 1-3 being Pomarine and 4 being Long-tailed.

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