Study reveals new information on the direct and indirect mate choice in lekking animals

Exactly what behavioral mechanisms determine variation in male mating success is important because different mechanisms may have different evolutionary consequences. In addition to competition for mates and mate choice, indirect mate choice can cause sexual selection on male traits. This is when females have preferences for “external traits” determined by male competition.

One suggested example is when females prefer to mate at certain sites that males fight over, claimed to be important in lekking animals. However, a new report published in the August 2005 issue of The American Naturalist finds that female great snipes are not attracted to centrally located males or previously popular sites on mating arenas (leks). The findings, which question the widespread beliefs about the lek mating system, were gathered by a team of Norwegian and Swedish biologists from a long-term study in the Norwegian mountains.

The team collected a large dataset during 14 years of studying great snipe at leks in the mountains of Norway, including nearly 1500 mating events and hundreds of individually marked males and females. They mapped every observed mating, kept track of where individual females mated from year to year, and where individual males held their territories. They conclude that great snipe females are certainly very choosy about with whom they mate, but not at all based on the outcome of male competition or other “external” cues. In this bird, females are in control of mating and it seems that males cannot improve their own mating success by performing well in competitive interaction with other males. This is very different from some other lek-systems, where male competition is indeed important.