Sexual selection in the Great Plains toad ( Bufo cognatus).

Most breeding aggregations lasted only 2 or 3 nights following summer rainstorms. Males substantially outnumbered females at choruses, and females actively selected mates from among displaying males. Some small males adopted satellite positions near calling males; the percentage of time a male was observed calling was significantly correlated with snout-vent length. Male mating success was positively correlated with the percentage of time a male was observed calling, but male size and mating success were not correlated. There was no indication of positive assortative mating with respect to body size. It is concluded that Bufo cognatus has a lek mating system. -from Author