Sex Pheromone in the Lobster, Homarus americanus

Abstract

SEXUAL recognition and attraction in many insects have been shown to involve chemical communicants called pheromones1, and these results are widely applied in agriculture2. In contrast very little is known about (sex) pheromones in crustaceans, the only experimental verification being that of Ryan3 who observed that males of the Pacific crab, Portunus sanguinolentus, displayed towards water from premoult females. No response was obtained after the excretory pores of the females had been sealed. A few other publications on crustacean behaviour and natural history suggest such a chemical communication system. Berry4 observed in Panulirus homarus that “male lobsters show sudden attraction to particular sexually mature females” and speculated that the tegumentary glands may be involved. Hughes and Matthiessen5 stated that “it appears as if the freshly moulted female (Homarus americanus) exerts a chemical attraction on the male”. Some other indications for the existence of a sex pheromonecan be found6 without experimental evidence, however. This lack of experimental evidence, even in reports on crustacean mating behaviour7, is remarkable considering the economic importance of such Crustacea as lobsters and shrimp and the benefits for culturing these animals, if a sex pheromone were known and available.