by Bruce MacPherson
Shorebirds in Vermont are a sometimes thing. Not so much our resident shorebirds-Wilson’s Snipe, American Woodcock, and the hard-to-find Upland Sandpiper-but rather the migratory shorebirds that breed in the Arctic tundra and migrate to and from the Gulf coast, Central America, and South America. Migrating shorebirds do stopover in Vermont, but their numbers vary from year to year. In the fall Dead Creek WMA in Addison is one of the more reliable locations in Vermont for shorebirds, especially in those years when the water levels at Dead Creek are drawn down to allow vegetation to regenerate. This year was different. Although the water levels at Dead Creek were drawn down early in the summer, river bottom plants regenerated quickly, covering the mud flats and producing less than ideal habitat for shorebirds. Fortunately, the dry summer of 2012 also produced very low water levels on Lake Champlain, resulting in welcoming mud flats at Delta Park, Shelburne Bay, and Button Bay among others. A bonanza of shorebirds resulted.
Which brings up the problem of shorebird identification. The good news is that shorebirds often stay put in one area while feeding, allowing birders to examine them closely. The bad news is that different shorebirds often look very much alike. Unlike warblers, for example, plumage differences between species are often not as helpful in shorebird identification. The ”peeps” (small shorebirds) are especially difficult to distinguish from one another. In the case of shorebird identification the concept of GISS (general impression of size and shape) becomes useful. The relative size and shape of the birds, subtle differences in bill length and shape, the extension of primary wing tips beyond the tail or not, provide important clues to identification. Without going into detail, the excellent book by O’Brien, Crossley, and Karlson, The Shorebird Guide, provides specific information about species identification with abundant illustrative photographs. Another source offering a concise guide to shorebird identification appeared recently on Bryan Pfeiffer’s informative blog, the Daily Wing, which can be accessed from the GMAS website or with a Google search.
Which brings me to the subject of Willets. This large, stocky shorebird with a stout black bill, long black legs, and striking black wing tips highlighted by a bold white stripe in flight is relatively easy to identify. Even in good shorebird years Willets in Vermont are uncommon. In fact, VT eBird, lists this species as “rare”. And so it came as a surprise in late August when a Willet was reported first at Delta Park and a few days later at Shelburne Bay. Whether these were two separate birds or the same bird is conjectural. Fortunately, a number of birders were able to observe and photograph these birds. But a question arose, which subspecies? Willets come in two varieties-Eastern and Western. After some chatter on the VTBird list Eric Hynes set the record straight in an informative post. Eric pointed out that the bird in question was larger and paler than the usual Eastern subspecies. Most tellingly, Western Willets breed in the prairies of the western United States and Canada, but migrate to the Atlantic coast and Gulf coast in late summer. Eastern Willets breed on the Atlantic coast, but migrate in late July and early August to Central and South America, hugging the coast all the way. By late August their migration is complete. In contrast, Western Willets migrate in late August and early September and may appear inland. End of story. Western!
Shorebird identification is challenging, but fun. As the story of these Willets illustrates, with good observations and photographs, a few reliable sources of information, and informed discussions among birders at all skill levels, we can all learn to identify most shorebirds. As the saying goes, where there’s a Willet, there’s a way.
Willet photo by Bob Dill used by permission