Conversations Under the Canopy: Aggregating Juvenile Mangrove Whiprays actively produce Sound

New evidence from Magnetic Island on the Great Barrier Reef, Australia, shows that the mangrove whipray (Urogymnus granulatus) can actively produce sounds. Juvenile mangrove whiprays appear to make loud clicking noises as an agonistic display, either to warn off and startle predators or to signal to other nearby juveniles to aggregate in defense. Though it is clear that elasmobranchs (sharks, rays, and skates) can hear and respond to sounds in various ways, until now, there have been no confirmed examples of active sound production by this group in the wild.