The Greater Yellowlegs is a mottled gray wading bird with long, bright yellow legs. It is similar in appearance to its smaller relative, the Lesser Yellowlegs. The bill of the Greater Yellowlegs is slender and longer than the diameter of its head, in contrast to the bill of the Lesser Yellowlegs, which is not significantly longer than its head. In breeding plumage, the bill is solid black, whereas in non-breeding plumage it may be lighter gray at the base. The bill may appear slightly upturned. The Greater Yellowlegs’ cryptic plumage is mottled brownish-gray and white, with the breeding plumage brighter and more heavily barred. An important field mark of the bird in flight is its white tail, which is barred at the end. Relative to its size, the legs of the Greater Yellowlegs are shorter than those of the Lesser, with the result that the toes do not project as far behind the tail in flight.