Scientists have recorded the song of a right whale for the first time, and not just any right whale – the eastern North Pacific right whale, the rarest of them all.
North Pacific right whales are so endangered it’s thought of the two populations – the eastern (found in the Bering Sea) and the western (off the coast of Russia and Japan) – there are only around 30 eastern North Pacific right whales left on Earth, and scientists think this is why the notoriously non-musical mammals have turned to song.
Compared to humpbacks, bowheads, and blue whales, right whales are the least musically-inclined whales in the sea, and though they demonstrate distinct vocalizations, the calls had never been heard in the repeating pattern we call whale song – until now.
In 2010, researchers from the National Oceanic and Atmospheric Administration (NOAA) were carrying out a field survey in the Bering Sea, off the Alaskan coast, when they heard the unusual pattern.
“We thought it might be a right whale, but we didn’t get visual confirmation,” said Jessica Crance, a marine biologist from NOAA Fisheries, and lead author of the study published in The Journal of the Acoustical Society of America.
“[W]e started going back through our long-term data from moored acoustic recorders and saw these repeating patterns of gunshot calls. I thought these patterns look like song.”
Their hesitancy at identifying the vocalists was prudent as right whales have never been heard singing before. They have quite the repertoire of sounds they use to communicate, from “gunshot calls”, which unsurprisingly sound like gunshots, to moans, warbles, and screams, but for it to be considered song it has to feature a repeating pattern.
It took seven long years for the researchers to prove their suspicions right, but finally in 2017 they heard the same songs again, and this time they confirmed visually as well as acoustically that they were coming from male eastern North Pacific right whales.
“We can now definitively say these are right whales, which is so exciting because this hasn’t been heard yet in any other right whale population,” Crance said.
An incredible wealth of information came with the confirmation. They recorded four different songs over the eight years, and recorded the same song in two different, distant locations at the same time, which shows multiple individuals can produce the same song.
Of the animals they could sex that were making the music, all were male, suggesting the displays are for whale wooing, though it remains unknown if the females sing.
“We have direct evidence of male right whales singing, and we think this may be exclusive to males, but we have very limited data on vocalizing female right whales,” Crance said.
“With only 30 animals, finding a mate must be difficult. Lone male right whales tend to gunshot more frequently than females. Perhaps the 2:1 male ratio in the North Pacific has led to our males singing to attract females. But we may never be able to test that or know for sure.”
Right whales, named as they were the "right" whale to be targeted – slow, swimming close to shore, with unusually buoyant carcasses – were hunted to near extinction for their oil, meat, and baleen up until the early 20th century. In 1937, commercial right whale hunting was banned, but recovery has been slow and riddled with setbacks from illegal hunting. They are now one of the most endangered species on the planet.