A few notable specimens from an impromptu visit to the Academy of Natural Sciences at Drexel University, last week. The museum is the oldest in the New World, boasting the 8th largest ornithology collection in the world, and 5th largest associated with a university. One of the highlights of my visit was looking over the Kumlien's-Thayer's specimens. Here's an adult type from Ellesmere Island, collected on 19 August 1934 (sex unknown). Skins from Ellesmere Island - presumably from the core of thayeri's range - have been difficult for me to find in the collections I've visited in the last few years.
p8-p10 retained (4th basic?), p7 dropped, p6 growing, p5 almost fully grown.
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The molt here is rather typical for a large gull in mid-August in the northern hemisphere. For what it's worth, the thayeri I see here on Lake Michigan in late October to early November are still molting/growing p9-p10 upon arrival, exhibiting molt migration.
The pigment on p8-p10 on this individual is somewhat extensive and pale. I'm writing this off as a adult type showing some seasonal fading/bleaching. Perhaps some of it is a collections artifact? Further, the p5-p6 subterminal bands were just a hint paler than I was expecting for a Thayer's taken from Ellesmere.
Next up is a presumed nominate fuscus, Lesser Black-backed Gull, from northern Egypt. Most interesting is the size of the p10 mirror (~48mm). This measurement seems to exceed ranges given in the literature. I'd appreciate some comments on this bird.
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| Lesser Black-backed Gull. |
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| Same LBBG (left) with Peruvian Kelp Gull (right). |
A special thanks to Jason Weckstein for showing me some of the gulls here!