The stamp "Berezinsky Nature Reserve. Ruff" from the "Fauna of the USSR" series was issued on August 25, 1975. Print run: 8,700,000 copies. Artist: N. Shevtsov.
The ruff is a bird in the sandpiper family. It prefers to nest in grassy marshes and wet meadows.
Male ruffs come in two types: typical males and faeders. Faeder males do not grow breeding plumage and do not take part in fights, but they are present at the lek. It is impossible to tell a faeder from a female by appearance. The only difference is that they are slightly larger than the average female ruff. However, it has been observed that females present at the lek often choose faeders for mating.
Faeder males have another peculiarity. Typical males often mate with them as well, even though they can recognize that faeders are male. This type of male, imitating females in appearance and behavior, was described not long ago, in 2006, and so far this is the only known case of such unusual behavior among birds.
"Faeder" translates as "forefather," and ornithologists believe that this is what male ruffs looked like before genetic changes occurred and the birds developed the breeding plumage we can observe today. On average, faeders make up about 1% of all male ruffs.
Typical males are also divided into dominants and satellites. Satellites are distinguished by a white ruff and a calm temperament. Aggressive dominants have colored ruffs, and all clashes occur between them. It has been noted that the brighter the ruff, the more aggressive the male.
Ruffs do not form a pair bond. A female can mate with several males at once, which satellite males often take advantage of. While the dominants are fighting, they manage to mate with the females.
Despite their seeming aggressiveness, males do not inflict any injuries on their rivals in fights. The main point of ruff battles is to win the prime spot on the lek, which may be a small rise or a tussock.
The female ruff incubates and raises her offspring on her own. Males take no part in this.