Ruff

The ruff is a medium-sized, long-necked, pot-bellied wader with a small head and medium-length bill. Males are much larger than females, called reeves: 29–32cm long and 130–254g, the largest of the Calidris sandpipers. In breeding plumage the male has bright head tufts, bare orange facial skin, much black on the breast and the large ornamental collar that gives the species its name, and these ornaments vary greatly between individuals. Females and non-breeding males are grey-brown above and mainly white below. The legs are pink to orange in adults (Wikipedia, general species account).

It breeds in marshes and wet meadows across northern Eurasia, where males display at communal leks; three kinds of male, including a rare female-like form, use different mating strategies. The female lays four eggs in a hidden ground nest and raises the chicks alone. It is highly gregarious on migration and in winter, sometimes in huge flocks, feeding mainly on insects and on migration taking rice and other grain (Wikipedia, general species account).