Wader of medium size, with a long bill that curves somewhat downward. a little bigger than a Dunlin, with longer legs and a longer, finer bill. Note the big white rump patch when in flight. Deeply rusty head and body plumage in breeding (similar to Red Knot). Birds that do not breed have grayish-brown plumage with white belly and eyebrows. The juvenile has a whitish underside with a varied buffy wash on its breast and is grayish above with clean scaly feather edgings.