Sex Pheromone Communication in the Sea Lamprey: Implications for Integrated Management

Abstract

Studies in the past two decades have demonstrated that sexually mature sea lampreys ( Petromyzon marinus) release sex pheromones that attract conspecific individuals of the opposite sex. Recently, electrophysiological, behavioral, and biochemical studies have shown that male sea lampreys, during spermiation (spermatogenesis), release 7α,12α,24-trihydroxy-3-one-5α-cholan-24-sulfate, or 3 keto-petromyzonol sulfate, which induces searching behavior in ovulatory females. This behavior appears to lead the females to nests occupied by males. The biosynthesis and release of this pheromone are likely to be regulated by the endocrine system and by environmental factors such as water temperature. Synthetic copies of this pheromone, if available, could be used for attraction and annihilation of mature female lampreys, or for disruption of mating. It may also be possible to develop procedures that promote pheromone biosynthesis in sterile males, which when stocked into spawning grounds, may make them highly effective in competing for mates with resident males. To develop protocols for implementing these potential strategies in integrated sea lamprey management, it is critical to fully understand pheromone biosynthesis and release in male sea lampreys, and to determine the role of sex pheromones in male reproductive fitness.