Thursday, April 24, 2014

Shorebirds

Last winter my dragonfly-guru, Scott King, read The Shorebirds of North America. In exchange for my showing him a yellowlegs, he promised me several odonates lacking on my list. I assured him that my part of this bargain this spring would not be challenging. On Tuesday, Scott and I easily found both species of yellowlegs, Greater and Lesser—the photograph above is of the Lesser. Note the short, needlelike, black bill.
Other shorebirds at the Randolph Industrial Park in Dakota County, Minnesota, proved a bit trickier to identify. I was not expecting these Dunlin to be in such drab basic plumage. Our first clue in the bird above was its relatively long, down-curved bill. In the subsequent two photos, note the black belly speckles and occasional reddish back feathers.
Dunlin winter on the coasts of North America, from Alaska and Maine south to central Mexico. They breed in the high Arctic. Other Dunlin breed across Arctic shores of the Old World and winter in more southern latitudes of that hemisphere.
The Dunlin were outnumbered by Pectoral Sandpipers (in the foreground of the third photo and landing in the last one). Note the dark, sharply defined breast streaking and the dark line through the tail feathers. These shorebirds breed in the high Arctic, both in northwest North America and northeast Siberia. North American and most Siberian birds winter from Peru to southern-most Argentina. A few Pectoral Sandpipers winter across the Old World, across the Pacific Ocean, Asia and Australia, Europe, and Africa. The hypothesis is that this sandpiper originated in the New World, and spread into the Old. Most Asian birds return to their ancestral wintering range in South America (Farmer et al 2013).

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