A group of animal biologists and chemists at the Institute of Transformative Bio-Molecules (ITbM) at Nagoya University in central Japan, in collaboration with other institutes have identified the pheromone involved in the mechanism that triggers puffer fish to spawn on beaches using moonlight ( Current Biology).
Along coastlines around the world, at the time of the spring tide (that is, new moon and full moon), thousands of puffer fish gather at the water’s edge and perform a writhing motion as they spawn. These fish are known as ‘semilunar spawners’. The researchers identified 125 genes involved in their spawning behaviour, including genes crucial for reproduction. During the spring tide, the researchers also noticed receptors for a particular pheromone, PGE2. When they applied PGE2 to a tank of puffer fish, both males and females demonstrated their characteristic writhing behaviour when spawning. Furthermore, as the dose increased, the number of responding fish also rose.
The researchers concluded that the spawning puffers release PGE2 into the seawater, triggering the synchronised beach-spawning behaviour.