Sightings of True's beaked whales are so rare that even the most devoted whale expert can go an entire career without ever seeing one in the wild. Researchers working near the Azores are now the first to ever capture underwater footage of these aquatic creatures in their natural habitat.
The new footage, captured by a research team from the Centre for Research into Ecological and Environmental Modelling at the University of St Andrew's in Scotland, shows two adult True beaked whales swimming with a calf near the Azores Islands in the North Atlantic.
In an accompanying paper published in PeerJ, the researchers offer new insights into this poorly-studied aquatic mammal. In addition to unprecedented footage, the researchers recorded a new colour pattern for these deep water whales, while also establishing geographical boundaries in the North Atlantic. These insights will allow marine biologists to better monitor the status of individuals and work to conserve the species.
As testament to their elusive nature, three new species of beaked whales have been discovered in the past two decades alone, bringing the total number of known beaked whale species to 22. Sightings are rare, and much of what's known about these creatures is derived from observations of decomposing bodies found on shore and breaching events.
Image: Roland Edler
Beaked whale behaviour explains why we so rarely see these creatures. They tend to live far offshore in deep waters, spending 92 per cent of their time underwater. Among whales, they are the masters of the deep, feeding at depths reaching 3000m and staying underwater for as long as two hours. These whales use their specialised beaks to suck up squid, fish and crustaceans. Following a big dive, they return to the surface and perform short, shallow dives at brief intervals. Unlike some whales and dolphins, they aren't attracted to boats.
For the new study, a research team led by marine biologist Natacha Aguilar de Soto performed a genetic analysis on two whales that were found a few years ago: One that washed ashore in El Hierro, Canary Islands in 2012, and one found floating dead near Faial, the Azores, in 2004. The purpose of the molecular analysis was to confirm the identity of the specimens as True's beaked whales; even beaked whale experts have a hard time distinguishing one species from another.
True's beaked whales have been known to breach the surface of the ocean, allowing for observations. (Image: Dylan Walker)
In conjunction, several observations of True's beaked whales (in addition to the new footage) in deep waters off the Azores and the Canary islands suggests these archipelagos may be prime locations for studying the enigmatic whales. Using data from previous research, the scientists were able to compile a map showing their likely geographic boundaries.
(A) Worldwide distribution of True's beaked whales and (B,C) the locations of the reports included in the new paper. (Image: N.A. de Soto et al., 2017)
Looking at the footage, the researchers were also able discern new colour patterns on True's beaked whale. The whale features a discernible white splotch that extends from the top "melon" portion of its head back to its blowhole above its eyes. "This coloration contrasts with previous descriptions for the species and it may be rare," write the researchers in their study, "but it exemplifies the variability of the colouration of True's beaked whales in the North Atlantic, further confirmed here by live sightings data." These new colour patterns should make it easier for marine biologists to identify these whales during future expeditions.
Drawing showing the newly discovered colour patterns. (Drawing by Vidal Martin/SECAC)
It's hard to believe that scientists are just now capturing the first footage of large mammalian species. But as this study shows, our oceans still have many secrets to tell.