Posted by Matthew Kenne (209.163.4.149) on October 16, 2001 at 20:19:48:
I agree with Tony and his bunch that the bird is second-summer, but I think it's a Parasitic. I don't put much faith in "jizz" or apparent proportions from one photo, so I'm betting on plumage (I picture Joe sitting there with a poker-face and a hand full of other shots of the bird!). Olsen and Larsson's Skuas and Jaegers says that second-summer Long-tails have adult-like primaries without the pale bases that the Parasitics have. The dark P10 caught my eye also. It's not Sibley, but several plates in Skuas and Jaegers show all the species with this feature to some extent on occasion, and some of the photos of Long-tails don't have it. The rounded "feather" to the right of the central retrices is odd. It's not in the correct position to be one of the elongated central retrices, but none of the other tail feathers have any business being this long. I'll bet that one of the other photos clears up this anomaly.