Omura's whales, the world's rarest whales, have been captured on film for the first time. An international team of scientists released a video and the first set of images of the said elusive whales swimming in the wild.
Led by Salvatore Cerchio from the Woods Hole Oceanographic Institution and the New England Aquarium, a team of international scientists analyzed the Omura's whales based on their vocalizations, habitat inclination and foraging methods using the population recently discovered off the coast of Madagascar.
Named after the Japanese cetologist Hideo Omura, very little was known about this rare and highly elusive whale species. Much of the previous data came from the analysis of Japanese scientists who in 2003 determined the species' existence by studying the mitochondrial DNA and morphology of very few captured specimens, which had been misidentified before as Bryde's whales.
The recent discovery off Madagascar's coast is the first conclusive proof of the species' existence, which provided thorough accounts of the Omura's whales' characteristics in the wild.
Cerchio's team was researching dolphins near Madagascar in 2011 when they came across three unfamiliar whales. At first, they thought they found Bryde's whales, but in 2012, they spotted four more of the unfamiliar whales in the waters. In 2013, they ventured into deeper waters and found 13 more of the unidentified whales, which include a mother-calf duo. They thought they had come across an entirely new species, but after a series of tests, they confirmed that they were Omura's whales. By 2014, they had already documented 44 sightings.
Omura's whales have long, narrow bodies built for speed in the waters. They are also asymmetrically colored – darker on the left, lighter on the right. Omura's whales also have light and dark stripes and patches across their bodies. This characteristic enables the species to be individually recognizable.
While Omura's whales population rate remains unknown, Cerchio expressed that they could also be in danger based on the noises emitted underwater by industrial explorations.
"Human noise is a pervasive threat across the oceans. Unfortunately, the effect is insidious and difficult to detect," said Cerchio. His team will resume the field study in hopes to estimate the whale population based on the Madagascar cluster.
The team published the findings in the Royal Society Open Science journal on Oct. 14, 2015.
Watch the Omura's whale swim in the video below:
Video from the first field observations of an Omura's whale swimming off the coast of Madagascar. So little is known about Omura's whales that scientists are unsure how many exist or how rare the species is. To date, the team has catalogued approximately 25 individuals through photographic identifications.
Posted by Woods Hole Oceanographic Institution (WHOI) on Friday, October 23, 2015