Stonefly nymphs use hydrodynamic cues to discriminate between prey.

摘要: Playback experiments conducted in a Rocky Mountain, USA, stream determined whether predatory stonefly nymphs (Kogotus modestus; Plecoptera: PerlodiMae) used hydrodynamic cues to discriminate prey species from nonprey species. In the laboratory we recorded pressure wave patterns associated with swimming escape behavior of Baetis bicaudatus (Baetidae), favored mayfly species, and those mayfly, Ephemerella infrequens (Ephemerellidae). We video taped responses 24-h starved Kogotus playbacks, playbacks or no made by oscillating (or not) live mayflies (Ephemerella) clear plastic models placed within situ flow-through observation boxes. The probability attacks per encounter was highest independent model type used, but also showed an unexpected high when were through Ephemerella. Thus, discriminated between only model. never attacked motionless models. allowed some successfully capture one small immediately before which resulted much higher on either heightened discrimination versus playbacks. under similar experimental conditions strikingly its response after successful capture. Order playback presentation (Baetis first first) did not influence patterns. This study is document use stream-dwelling predators for provides mechanism explain selective predation stoneflies nature.