The Ruff is a medium-sized wading bird that breeds in marshes and wet meadows across northern Eurasia. This highly gregarious sandpiper is migratory and sometimes forms huge flocks in its winter grounds, which include southern and western Europe, Africa, southern Asia and Australia. The Ruff is from the family of Sandpipers.
This bird is a long-necked, pot-bellied bird, often described as having a gravy boat appearance. It shows marked sexual dimorphism; the male (29-32cm, 180g, 54-60cm wingspan) is much larger than the female (the reeve), and has a breeding plumage that includes brightly coloured head tufts, bare orange facial skin, extensive black on the breast, and the large collar of ornamental feathers that inspired this bird's English name. The female and the non-breeding male have grey-brown upperparts and mainly white underparts.
During the breeding season Ruff eat only insects (adult and larvae). Whilst on migration and during winter they also eat crustaceans, spiders, molluscs, worms, frogs, small fish, and also the seeds of rice and other cereals, sedges, grasses and aquatic plants. The Ruff stores fat as a fuel, but unlike mammals, uses lipids as the main energy source for exercise (including migration) and, when necessary, keeps warm by shivering; however, little research has been conducted on the mechanisms by which they oxidise lipids.
Males display during the breeding season at a lek* in a traditional open grassy arena. The Ruff is one of the few lekking species in which the display is primarily directed at other males rather than to the females. There are three male forms: typical territorial, satellite males and the faeders. Ruffs have one of the highest levels of polyandry** known for any avian lekking species and for any shorebird.
The nest is a shallow ground scrape lined with grass leaves and stems, and concealed in marsh plants or tall grass. Males play no part in the nesting or chick care and leaves the breeding grounds a month before the female and juveniles.
[All Text above: Ref (129)]
* A lek is a gathering of males, of certain animal species, for the purposes of competitive mating display. Leks assemble before and during the breeding season, on a daily basis. The same group of males meet at a traditional place and take up the same individual positions on an arena, each occupying and defending a small territory or court. Intermittently or continuously, they spar individually with their neighbors or put on extravagant visual or aural displays. [Ref (130)]
** polyandry is a type of breeding adaptation in which one female mates with many males. [Ref (131)]
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