Sharks and rays have long been considered “silent” fish – that is, unable to produce sound. Researchers from Sweden and Australia have now shown that this is a misconception, writes SLU (Swedish University of Agricultural Sciences) in a press release.
According to the study, at least two species of stingrays may intentionally produce sound, probably as a defensive or warning behaviour.
The skirts made a clicking sound when the diver was close. Photo: Brian Bransch Price/AP/TT
The authors present several recordings in which wild fish of two species of stingrays intentionally produce sound. The sounds are characterised by a series of very short and powerful clicks, probably for warning or defensive purposes. In all recordings, the rooster started producing sound when the filmer got really close, and stopped when the distance increased.
“The fact that we have only now realised that these common stingrays produce sound shows once again how much we still have to learn about the oceans,” says Lachlan Fetterplace, lead author and researcher at SLU.
The results were recently published in the scientific journal Ecology.
Cartilaginous fish are jawed vertebrates that include sharks and rays. Cartilaginous fish differ from bony fish by their cartilaginous skeleton and the lack of a swim bladder. The group today includes over 1,000 species, almost all marine.
Due to their special jaw construction, with the jaw joint at the back, many have a characteristic head shape, with a protruding nose and mouth on the underside of the head.
Because the fish lack a swim bladder, cartilaginous fish sink to the bottom if they do not keep moving.
Source: NE, SLU
