Tuesday, September 6, 2005

Buff-breasted Sandpiper, terns at Maumee Bay SP

Tuesday Sept. 6: Just back from Europe and more than a little jet-lagged, I read more than 300 e-mails starting at three a.m., and then decided to go out to Maumee Bay State Park, Lucas County, where Brian Zwiebel had reported Buff-breasted Sandpipers a week ago. Kim and I arrived a little after 8:00 and soon found four Buff-breasteds working along the grassy strip between the last parking lot and the Lake Erie beach. These amazingly tame birds moved around a fair amount, at one point flying over to the lawn behind the lodge. We found that if we sat down in the grass and watched, the birds would walk up within a few feet of us.

The adjacent beach also offered superb opportunities for looking at terns. Although we saw no unusual species, the numbers were outstanding; I estimated about 1,500 to 1,600 Common Terns and 400 to 500 Forster's Terns. With so many available for study and comparison, it was possible to go through and find individuals that could have posed identification problems if they had been seen alone. For example, a few of the adult Forster's were still in a stage of molt where they had a lot of blackish extending across the nape, not just isolated black "ear" patches, and they could have been mistaken for Commons. Another tricky stage (just saw one this morning, but I've seen it a number of times before) is a Forster's with its bill changing to the all-black condition of winter; they sometimes appear to have a black bill with a pale tip, very superficially suggesting the pattern of Sandwich Tern.

The majority of the terns were Commons, and it was fascinating to see the variation in bill color in the adults that were changing. Many of them showed bills that were more or less solid dark red, as if the bill were uniformly fading toward black. A few had the bill entirely red, even bright red, with only a hint of dusky at the tip. These bright-billed birds also had rather bright red legs, gray underparts, and virtually solid black caps, so they were still essentially in latter stages of breeding plumage. Only in recent years have we realized how common it is for Common Terns in late summer to have all-red bills. Such individuals undoubtedly have been responsible for reports of Arctic Terns out of range. It's very useful to be able to study such birds in this "controlled" situation where their bill shapes and other characteristics can be compared directly to other individuals.

Other birds present included a few hundred Ring-billed Gulls, smaller numbers of Herring and Bonaparte's Gulls, two juvenile Baird's Sandpipers on the sandy beach, a Ruddy Turnstone along the shoreline, and flyover Lesser Yellowlegs and Solitary Sandpiper. Several small flocks of Bobolinks flew over, calling, while we were there.

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