New whale species discovered in Bering Sea
Black, beaked whale new to science, but nicknamed karasu or raven by Japanese whalers
Scientists have made the rare discovery of a new whale species.
The new species doesn't yet have a name, but the beaked whale is black and lives in the Bering Sea between Japan and Alaska, researchers report in the journal Marine Mammal Science this week.
They identified the new species through the genetic analysis of samples from eight specimens.
While it wasn't previously known to science, Japanese whalers had already given the species the nickname "karasu," Japanese for raven. They thought it was a variant of the larger, more common Baird's beaked whale rather than a separate species.
The new genetic analysis shows that, in fact, the whale is genetically distinct from Baird's beaked whale and more closely related to another species called Arnoux's beaked whale, which only lives in the Southern Hemisphere.
Once in 2 decades discovery
The discovery of a new whale or dolphin happens usually only once every couple of decades, said Philip Morin, a researcher at the U.S. National Oceanic and Atmospheric Administration's Southwest Fisheries Science Centre in La Jolla, Calif., who led the new study.
In this case, the species belongs to a group — beaked whales — that live so far offshore and feed on fish and squid in such deep waters that they are rarely seen and almost never wash ashore, Morin said.
Japanese researchers were the first to suspect that the new species might exist, based on a genetic analysis in 2013 of three black beaked whales that had washed ashore in northern Japan.
"But they had such little evidence with just these three animals from one location that they suggested more research was necessary," Morin said.
He decided to see if there were any genetic matches to that type of whale among the 50 samples thought to be Baird's beaked whales in the Southwest Fisheries Science Centre's collection. Two of them matched.
"They were tiny bits of tissue, probably about the size of a pencil eraser, in a tube in a freezer," he said. "But from that, we could trace back to the animals they were collected from."
One was a dead, adult male whale found floating and wrapped up in kelp off Alaska's Aleutian Islands in 2004. The skeleton was subsequently studied and measured by researchers, cleaned, reassembled, and hung up in a local high school, providing valuable data about the whale's entire body.
Researchers were lucky enough to get another entire body when one washed up on St. George Island, one of the Pribilof Islands in the Bering Sea in 2014, while the study was already underway. That was also an adult male.
The Alaska and St. George Island whales were 6.6 and 7.3 metres long, suggesting their species is a little bit smaller than a Baird's beaked whale, whose adult males average 10 metres.
They also showed the scars of shark bites on their bodies, suggesting that like other beaked whales, they spend part of the year in tropical waters.
Morin and his colleagues managed to find two more samples among skulls labelled as Baird's beaked whales in other museum collections.
Now, with five new specimens from around the Bering Sea, in addition to the three analyzed in Japan, the researchers are confident that they've identified a new species — one that is likely quite rare. Morin says the Japanese researchers are in the process of writing a formal description including detailed measurements of characteristic body parts such as their skulls.
Morin hopes that now that scientists and the public know the new whale species exists, they'll begin to start looking for it.
"They're going to try and get pictures of it. It spawns a lot of new research. That's exciting," he said.
One unfortunate aspect of the discovery is it appears the whale lives in an area where it could be impacted by human activities like oil and gas exploration, which often involves setting off underwater explosives as part of seismic testing. That can damage whales' hearing and disrupt their use of echolocation to hunt for food.
Morin says now that people know of the whale's existence, companies conducting seismic tests should be aware that it's there and could be potentially impacted.