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The ‘raven’ whale: scientists uncover new beaked whale

Jeremy Hance
  • In 2014, a teacher stumbled upon a strange-looking whale that had washed up on a beach in Alaska.
  • The new whale looked similar to Baird’s beaked whale, but was darker and had a larger dorsal fin and a unique skull.
  • Recently released genetic evidence shows the whale is indeed a new species, as distinct from Baird’s beaked whale as it is from its closest Antarctic relative.
  • Beaked whales are the world’s deepest-diving mammals – surpassing even the sperm whale. Many species remain little studied.

If humans need a reminder of our collective ignorance about the natural world than here’s a really good one: scientists believe they have discovered a new species of whale. You read that right: a new whale. Scientists identified the new cetacean by a bizarre carcass that washed up in the Alaskan Aleutian Islands in 2014. At first, locals believed it was a Baird’s beaked whale (Berardius bairdii), but grew suspicious due to noticeable differences. Subsequent DNA tests have shown that the corpse is very likely a member of a species unknown to science, smaller and darker than its cousin, the Baird’s, with a larger dorsal fin and a distinctly shaped skull.

“Clearly this species is very rare, and reminds us how much we have to learn about the ocean and even some of its largest inhabitants,” Philip Morin, the lead author of the study describing the discovery, said in a press release. Morin is a molecular biologist with NOAA Fisheries’ Southwest Fisheries Science Center; his team’s results on the whale were published yesterday in Marine Mammal Science.

In order to determine whether or not the 24-foot-long (7.3-meter) animal that washed up two years ago in the small Alaskan community of St. George was a new species, Morin and his team analyzed DNA samples from 178 beaked whale samples from across the Pacific. They discovered that it was indeed a new species, one that had long been hiding in plain sight. Eight DNA samples—including one from the Smithsonian Institute collection and another from a skeleton hanging in a high school gym in Alaska—came from this new species and not Baird’s beaked whale as long believed. The DNA also showed that the new whale is actually more closely related to Arnoux’s beaked whale (Berardius arnuxii) from the Antarctic than it is to Baird’s, though all three belong to the same genus.

The new whale has also been seen in life, albeit rarely. Japanese whalers—who still hunt beaked whales—have long referred to the new whale species as karasu, or raven, due to its darker body color.

“Japanese whalers have known about the black form but didn’t consider it a separate species,” said study co-author Erich Hoyt, a researcher wit the Whale and Dolphin Conservation in the UK and co-director of the Russian Cetacean Habitat Project.

Beaked whales are arguably the most elusive and mysterious mega-animals on the planet. Scientists have currently described at least 22 species but the lifestyle of these whales makes them incredibly difficult to study. Beaked whales are the world’s deepest diving mammals, commonly going deeper than 1,000 meters and then blithely feeding at these crushing depths for over two hours.

In 2014, scientists documented a Cuvier’s beaked whale (Ziphius cavirostris) diving 9,816 feet (2,992 meters) down for more than 135 minutes. A sperm whale has only been tracked to about 3,280 feet (1,000 meters) down, while a modern nuclear submarine would collapse at less than 2,625 feet (800 meters).

According to the National Oceanic and Atmospheric Administration (NOAA), Baird's beaked whales are capable of diving to depths of 9,840 feet (3,000 meters).
According to the National Oceanic and Atmospheric Administration (NOAA), Baird’s beaked whales are capable of diving to depths of 9,840 feet (3,000 meters).

 

Almost nothing is known about the new beaked whale’s behavior. However, scientists believe it spends some time in tropical waters—like many other beaked whale species—due to telltale tropical shark bites found on the Alaskan corpse.

Scientists also have no idea how rare or common the species is, though they suspect the former. When it comes to conservation, scientists have little to go on for any of the world’s beak whales. To date, only two have been adequately assessed by the IUCN Red List: Cuvier’s beaked whale and the southern bottlenose whale (Hyperodon planifrons). Both of these are considered Least Concern by the IUCN. But the other 20 species have all been listed as Data Deficient, meaning scientists have too little information to make any kind of assessment about their endangerment status.

Other potential beaked whales aren’t even on the list. Just two years ago, another group of scientists proposed a new species of beaked whale—the pointed beaked whale (Mesoplodon hotaula)—also based on DNA research. But to date the IUCN hasn’t taken a look at this species, and is still lumping it in with the gingko-toothed whale (Mesoplodon ginkgodens).

Given how little is known about beaked whales overall, it is difficult to tell what might threaten these cetaceans. But scientists believe beaked whales may be acutely sensitive to mechanized sonar, potentially leading to mass deaths. Studies have also found high levels of toxic materials like heavy metals in beaked whales, likely due to their role as top predators. Dead beaked whales have also been found with plastic debris in their stomachs. In 2011, a beaked whale in New Zealand is believed to have been killed by ingesting a single plastic shopping bag.

“Discovering a new species of whale in 2016 is exciting but it also reveals how little we know and how much more work we have to do to truly understand these species,” Hoyt said.

The new species of beaked whale has not yet been named—that has to wait for another paper comparing it formally to its relatives. But since Japanese whalers have long been calling it the karasu whale—the raven whale—perhaps it may become Berardius corvis.

 

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