Chemical orientation of the crayfish Procambarus clarkii (Girard, 1852) to conspecific sexes and commercial fish feed.

Semiochemicals of crustaceans have not been fully investigated yet even if they are promising for applying as low impact control methods of invasive alien species. In the present study, responses of both sexes of the red swamp crayfish, Procambarus clarkii (Girard, 1852), to chemical stimuli from conspecific males and females and from a commercial fish feed are reported. Stimuli were assessed in two-choise tests carried out in a rectangular chamber. Crayfish response was recorded according to (1) the first choise and (2) the time spent by each animal on the left or right side of the chamber. Males were significantly attracted to females and feed but when these stimuli were simultaneously tested a specific males or females. Results confirm that female produces a sex pheromone, although its attractant power is not stronger than the feed used.