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

Semiochemicals of crustaceans are promising for setting up low impact control methods of invasive alien species. In the present study the orientation response of both sexes of the Louisiana red swamp crayfish, Procambarus clarkii (Girard, 1852), to chemical stimuli from conspecific males and females and a commercial feed was evaluated. Stimuli were assessed in two-choice tests carried out in a rectangular chamber. Crayfish response was recorded according to (1) the first side choice and (2) the time spent by the animal in the left and right side of the chamber. Males were significantly attracted by females and feed, but when simultaneously presented with these two odour sources no male preference was observed. Females were attracted by feed but not by male or female odour. Results confirm that P. clarkii females produce a sex pheromone but its attractant power was not stronger than a commercial feed.