Until recently, it was thought that stingrays were the silent type, going about their underwater business without making a peep. It’s time to retire that notion. Video evidence shows that some stingrays can make loud clicking noises.
An international research team led by marine ecologist Lachlan Fetterplace of the Swedish University of Agricultural Sciences published its findings on stingray noises in the journal Ecology in July.
The two ray species covered in the study are the mangrove whipray (Urogymnus granulatus) and the cowtail stingray (Pastinachus ater). A video compilation lets landlubbers listen in on the stingrayswhich sounds a bit like a wood clave rhythm instrument or hands slapping together.
Stingrays are elasmobranchs, a notoriously quiet group of animals that also includes sharks and skates. “There have been no confirmed examples of active sound production by elasmobranchs in the wild, despite attempts to record the behavior outside of captive settings,” the paper said. A study from 1970 had shown cownose rays would make sharp clicks when forcefully prodded, but those were captive animals.
The researchers believe the clicks were meant as warning or defensive sounds. “In all video recorded observations, a ray began producing sounds in response to an observer approaching closely, and ceased sound production when the distance between the ray and observer increased,” the Swedish University of Agricultural Sciences said in a statement last week.
Now that scientists know stingrays in the wild can voluntarily make clicking noises, they’re curious as to how the animals generate the sounds. It may involve contractions of body parts around the head and gills.
The researchers hope to find evidence of more stingrays and other elasmobranchs making noises. Said Fetterplace, “That we only just realized that these commonly encountered stingrays are making sounds, demonstrates, once again, how much we still have to learn about the oceans.”