DBQ answers

12 03 2015

Occasionally, I feel daunted when writing up these supposedly correct DBQ answers. Actually, most of the time I feel daunted. I am hardly an expert birder, and while my confidence in identifying our bread and butter dead bird species–loons, herring gulls, scoters–is high, when it comes to rarities, I often stumble. I was feeling additionally daunted, momentarily, by the international nature of our Bird A. Then, I very quickly remembered that we study seabirds here at SEANET, and seabirds scoff not only at international borders, but at the very idea that the Atlantic Ocean would be a barrier to their travels. For truly sea-faring birds, the Atlantic, or the polar oceans in the aggregate, are home turf, and many of their ranges are, in fact, circumpolar. Overall, the suite of species we see washing up on our beaches on the east coast tends to match what turns up on Scottish beaches, or Danish ones, better than what turns up on our west coast friends’ beaches in California or Washington. So, somewhat less daunted, I considered Bird A (which, full disclosure, came pre-identified for me by Edward, who sent the picture.)

**update: feeling MORE daunted now, after spending an hour writing up a fabulous breakdown of the identification here, and then losing it to a computer crash on my less than stellar work machine. So, here is the brief and aggravated version of the lyrical prose piece I labored over and lost:**

Bird A options: one of the jaegers, or one of the skuas. n.b., we Americans call jaegers jaegers and skuas skuas. Europeans call the whole lot skuas, which seems sensible since the four species that are candidates in a case like this are all actually in the same genus, Stercorarius. The birds we call jaegers here, specifically the pomarine and the parasitic, are both smaller, more delicate birds than the south polar and great skuas, not that one can say much about overall daintiness from this headless carcass. One thing that does leap out at me about Bird A is the tail, which is fairly short and blunt. This contrasts rather well with the longer tails of the jaegers, though juvenile jaeger tails are substantially shorter than those of their esteemed elders. Lest ye lose hope though, here’s a helpful bit of information: while juvenile jaegers do have short tails, they also have gray legs with black toes! A very dapper combination. The gray can be very extensive (see photo below of a jaeger that got a lot of attention in Texas), or run only just beyond the tarsal (“ankle”) joint, but our Bird A has no gray in evidence anywhere on the legs or feet, which appear entirely black (aside from that bit of silver jewelry its sporting).

A jaeger that caused an identification kerfuffle on Kirby Lake in Texas.

A jaeger that caused an identification kerfuffle on Kirby Lake in Texas.

So, not a jaeger then. Let us conclude that it is a skua. What kind of skua? The call generally comes down to plumage color, with South Polar Skuas being grayer, and Great Skuas browner overall, but with the dreaded exceptions, overlaps, and light and dark morphs. Terrible stuff. I can convince myself that I see some warm brown tones at the tail base and a bit along the wings, but mostly, I am persuaded by the fact that Edward sent me this picture with the note, “Great skua. Found on Texel Island, ringed in the Shetlands.” If there are field marks I am missing here that might help, please enlighten me!

Great Skua field marks. I can't get enough of these composite images. And I think that raincoat clad person is going to meet a bad end.

Great Skua field marks. I can’t get enough of these composite images. And I think that raincoat clad person is going to meet a bad end.

As for Bird B, I reserve that for the next post since I am feeling chagrined about the tragic loss of my first post, and also, I enjoy keeping Ray Bosse, who found Bird B, in suspense.

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