Do you ever hear a new song and realize it’s unlike anything you’ve heard before? I felt that a few times this year, mostly with Phoebe Bridgers and Polo G. It happened to scientists recently, too. But it wasn’t a new singer or rapper they discovered; it’s a new population of whales.
In a study published in the journal Endangered Species Research last week, scientists analyzed underwater recordings from the Arabian Sea, extending from the coast of Oman as far south as Madagascar. The team of researchers came across an unfamiliar kind of whale song that had never before been documented in 2017, sparking an international effort to discover the new singer.
“It was quite remarkable to find a whale song in your data that was completely unique, never before reported, and recognize it as a blue whale.” Salvatore Cerchio, director of the African Aquatic Conservation Fund’s Cetacean Program and study co-author, said in a statement.
A year after first discovering the unique song, the team brought their findings at a meeting of the Scientific Committee of the International Whaling Commission. There, they connected with other scientists who said they’d come across the same whale song in recordings from the central Indian Ocean. The two teams of scientists combined forces to learn more.
As the group analyzed the novel tune, it became clear that it was sung by a previously undiscovered population of blue whales in the western Indian Ocean. As they continued to amass data, they found that the new population likely spends most of its time in the northwestern Indian Ocean.
The exciting discovery is a glimmer of hope for blue whales, which have been pushed to the brink of extinction and are currently listed as endangered under the Endangered Species Act. In the 1800s and into the 1900s, the commercial whaling industry nearly wiped them out. Thanks to environmental protections, blue whale populations have been increasing around the world in the past half-century, but the species still faces global threats, chiefly due to habitat loss from climate-induced changes to ocean temperature and pH levels, as well as marine pollution. Ships also put the largest creatures on Earth at risk of being struck or getting tangled in fishing lines.
In light of the discovery that there are even more blue whales out in the oceans than scientists previously thought, the study’s authors say world leaders should redouble their efforts to protect the species by imposing stricter regulations on shipping and curbing carbon emissions.
Blue whales play important roles in their ecosystems and are essential in marine food chains. As the largest creatures on Earth, they eat wild amounts of krill and other small creatures, regulating ocean ecosystems. They also sequester carbon at a rate greater than trees. Also they’re whales. They rule. It’s possible that the whales the scientists found in the Indian Ocean aren’t simply a distinct population, but a unique subspecies of blue whale, which would make their conservation particularly important due to the need to preserve biodiversity both because it’s good for us and the natural world at-large.
“This is an urgent requirement in light of the wide range of threats to large whales related to expanding maritime industries in the region,” Andrew Willson from Five Oceans Environmental Services, LLC, who led the deployment of the research team’s recording units, said in a statement.