Friday, November 7, 2008

the holy graelsii

Like I said last post, it's not a birding trip ... but I did get out for 2 hours this morning to First Landings State Park to (successfully) look for my lifer brown-headed nuthatch. And though it's not a birding trip, I did manage about 60 images on the beach during naptime (hooray nappytime). I focused mainly on the lesser black-backed gulls (L. fuscus graelsii) since we don't get them in great numbers in Michigan, finding multiple individuals of most of the age groups.


First is a juvie. Both of the first two pics are of the same bird. In the lighting of the first pic it has the cold dark brown typical of the plumage, in the low evening sun of the second it takes on more Herring gull warmer medium tones. ID points include the very long primaries (which I cut off on the first pic), the very neatly marked wings (especially of the greater coverts), and the cold dark gray tertials with narrow white edging:








I'm not entirely sure of the age of this bird. I think it's acquiring 2nd winter plumage given the (scant) gray coming into the back and scapulars, but it still has the juvie pattern (though very faded and blurred) of the coverts. I think (though I don't have the literature with me to be for sure) that this species probably moults its wing coverts as it acquires 2nd summer plumage as the 2nd winter typically has solidly medium brown wing coverts. I think this bird probably skipped that step. The tertials have the charcoal gray feathers with bright white marbling at the edge typical of 2nd winter plumage for lesser black-backed's though:




Here's a more typical individual acquiring 2nd winter plumage with charcoal gray feathers making their way into the mantle and coverts. Its eye is lightening (the previous bird's was dark). It too sports the brightly marbled tertial edges:



Moving along, we have the 3rd winter bird. It has nearly acquired the adult look to the back and wings, has a bright eye, but has the very dirty bill typical of this age group in this species. This one's legs are still fleshy-pink. Note this bird is also moulting its primaries and so appears short-winged:


Finally we come to the adult winter type birds. They have a quite variable amount of head streaking. Both of these 2 are middle of the road. The first bird's primaries are probably missing at least 2 feathers as they're very short:






I think lesser black-backed is probably my favorite gull of the medium and dark backed group (it'd probably be Iceland amongst the whitewings and Little for the hooded group (though I reserve the right to change those picks should I ever see an ivory or Sabine's gull. Not sure where Ross's would fit in...)







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