An international team led by researchers from the Monash University found that grey seals (Halichoerus grypus) can clap their way into a date.
Marine mammals such as whales and seals aren't afraid to be vocal. They're highly social animals and use all sorts of calls and whistles to chat with their friends. But grey seals aren't afraid to take a more hands-on approach when it comes to finding a mate, and they will clap for love. This is the first time seals have been seen clapping completely underwater of their own accord.
"The discovery of 'clapping seals' might not seem that surprising, after all, they're famous for clapping in zoos and aquaria," said lead study author Dr David Hocking from Monash University's School of Biological Sciences.
"But where zoo animals are often trained to clap for our entertainment -- these grey seals are doing it in the wild of their own accord."
The findings are based on video footage collected by naturalist Dr. Ben Burville, a Visiting Researcher with Newcastle University and paper co-author, after 17 years of diving and observing the animals.
During the breeding season, the authors report, males voluntarily engage in underwater clapping. The team believes this is meant as a show of strength to intimidate competitors and attract potential mates. While it may sound very cute, the claps themselves are “impressively loud”, according to Dr. Burville, producing a gunshot-like sound. He recounts that at first "I found it hard to believe what I had seen.”
"How could a seal make such a loud clap underwater with no air to compress between its flippers?," he adds.
This isn't the only known case of marine mammals engaging in 'clapping': the behavior is relatively common among the group, with other species producing "similar types of percussive sound by slapping the water with their body or tail," said Associate Professor Alistair Evans from Monash University, co-author of the paper. However, it is the first time this behavior was seen for grey seals in the wild.
"Depending on the context, the claps may help to ward off competitors and/or attract potential mates," Dr Hocking said.
"Think of a chest-beating male gorilla, for example. Like seal claps, those chest beats carry two messages: I am strong, stay away; and I am strong, my genes are good."
The findings show that there is still much to learn about the animals we share a planet with. Furthermore, it showcases how impactful noise pollution can be for marine species in general and grey seals in particular. Clapping seems to be an important social behavior for the seals, so anything that could disturb it could impact breeding success for the whole species.
"Human noise pollution is known to interfere with other forms of marine mammal communication, including whale song," Dr Hocking said. "But if we do not know a behaviour exists, we cannot easily act to protect it."
The paper "Percussive underwater signaling in wild gray seals" has been published in the journal Marine Mammal Science.