Separation of basic-plumage Dunlin and Curlew Sandpiper can be quite challenging outside of alternate plumage, especially in the New World where the predominant subspecies of Dunlin (hudsonia and pacifica) have longer bills that their European and Asian counterparts. In fact the bills of North American Dunlin are often equivalent in length to Curlew Sandpiper, a point that may not be adequately addressed in European guides.
A long time ago I prepared a web page that touches on this topic: http://www.oceanwanderers.com/BSmallSHorebird.html The lengthy commentaries at the bottom of this page and spilling over onto additional pages, testifies to the knotty nature of this ID problem. Looking at Arie's photos of the Cupsogue bird, my inclination is to call it a Dunlin. The body seems too chunky for Curlew Sand, lacking the more gangly profile of the latter species. The legs of Curlew Sands always seems a little too long and spindly for their body and bill, but this bird has better proportions, fitting with the proposed ID as a Dunlin. The bill is long, but as I said above, this is typical of many female hudsonian Dunlins. Lastly, the bird has a fairly uniform smear of light spotting across the upper breast, which again is a pro-Dunlin feature. In terms of date, I believe we are still early for most returning Dunlin but the rules are far from absolute and probably of no use in terms of identifiying individual birds. I will add that this is not an juvenile of either species, which makes sense. As I recall Dunlin juveniles rarely move south before late August and show rows of dark centered scapulars, which I cannot detect in the photos. Juvenile Curlew Sand is buffer in color with a unique patterning on the upperparts. Hope this helps, Angus Wilson New York City, NY -- NYSbirds-L List Info: http://www.NortheastBirding.com/NYSbirdsWELCOME http://www.NortheastBirding.com/NYSbirdsRULES http://www.NortheastBirding.com/NYSbirdsSubscribeConfigurationLeave.htm ARCHIVES: 1) http://www.mail-archive.com/nysbirds-l@cornell.edu/maillist.html 2) http://www.surfbirds.com/birdingmail/Group/NYSBirds-L 3) http://birdingonthe.net/mailinglists/NYSB.html Please submit your observations to eBird: http://ebird.org/content/ebird/ --
