written by Darren Malone
Seals like most aquatic animals communicate through vocal calls but a new paper ‘Percussive underwater signalling in wild gray seals’ written by David P. Hocking and his team documents grey seals clapping underwater for the first time, the behaviour was documented in male seals of the coast of the Farne Islands in England. It is thought that the behaviour is used to show strength as a method of advertising to potential mates and to warn off competitors during the mating season.
We’ve all seen seals clapping either on television or in zoos when prompted by trainers but this study documents seals clapping of their own accord and took researcher Dr Ben Burville seventeen years of diving to capture on video. The footage shows a male grey seal clapping his two front flippers together to produce a loud sharp crack-like sound that can reach frequencies of >10 kHz. The claps have a higher frequency range then vocal calls as well as matching the optimum hearing sensitivity of pinniped hearing at around 10 – 30 kHz allowing the clap to cut through background noise and stand out as a clear signal to any other seals in the area.
The claps exhibited by the seals are very similar to a “knocking” vocalisation frequently recorded on hydrophones and could indicate that some of these recordings that have been documented as the knocking vocalisation could in fact be this newly recorded clapping behaviour, perhaps changing how we think about grey seal interactions.
The male in the video claps twice in response to a second male that crosses his path and a response clap can be heard from the intruder, it is also worth noting that a female was recorded swimming in the area prior to the interaction of both males. When the female returns our male is seen giving two claps in response, because male grey seals have been documented clapping in the presence of both males and females it is believed that the seals use this behaviour much like other animals do to both signal that they are strong and not to be contended with for potential rivals and that they are strong and healthy with good genes for potential mates.
The discovery of this new behaviour shows just how much there still is to learn about these and all animals in the world around us and further demonstrates the importance of noise communication in the breeding success and survival of the Grey Seal species and how it can be impacted by noise pollution from anthropogenic sources, highlighting the need for this species to be protected and studied as without the knowledge of these behaviours we can’t take steps to protect them.
References
David P. Hocking, Ben Burville, William M. G. Parker, Alistair R. Evans, Travis Park, Felix G. Marx. ‘Percussive underwater signalling in wild gray seals.’ Marine Mammal Science, 2020; DOI: 10.1111/mms.12666
Photos were taken from Pixabay.com
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