One of the most elusive whales in the world has been caught on camera. An international team of researchers made the first field observations of Omura’s whales off the coast of Madagascar.
For years, the species was mistaken for Bryde’s whales because of their similar appearances, both as small tropical baleen whales with like dorsal fins. But Omura’s whales are smaller in size and have unique markings on the jaw that are white on the right side and dark on the left.
In 2003, genetic data confirmed that the Omura’s whales were a distinct species, but there have been no confirmed sightings of the animal in the wild.
Until now, that is.
So little is known about Omura’s whales that scientists are unsure about how many of the species exist. But the researchers who observed the whale for the first time in the wild published a paper in the Royal Society Open Science journal that described the whale’s foraging and vocal behaviors, as well as habitat preferences in the shallow waters of coastal Madagascar.
The scientists have been conducting field research off the northwest coast of Madagascar since 2007 and first spotted an Omura’s whale in 2011, but misidentified it as a Bryde’s whale. After moving study areas in 2013, more sightings occurred and the team noticed the whales’ unique markings, leading them to believe they might be Omura’s whales.
Over two years, the researchers observed 44 groups, including four mothers with young calves. They collected skin biopsies from 18 adult whales, which confirmed the whales’ were, in fact, Omura’s whales, and cataloged approximately 25 individuals with photographs. The team also used hydrophones to record song-like vocalizations that may indicate reproductive behavior.
The study’s lead author Salvatore Cerchio says:
“What little we knew about these whales previously came primarily from eight specimens of Omura’s whales taken in Japanese scientific whaling…and a couple strandings of dead animals in Japan. This is the first definitive evidence and detailed descriptions of Omura’s whales in the wild and part of what makes this work particularly exciting…They appear to occur in remote regions and are difficult to find at sea because they are small–they range in length from approximately 33 to 38 feet–and do not put up a prominent blow.”
Cerchio returned to the field in November to further study the whales’ behavior, vocalizations and population characteristics. He hopes to produce the first estimate for any population of Omura’s whales with this work.
Featured image from Salvatore Cerchio et al. 2015