Extremely Rare True’s Beaked Whale Caught on Video

The True’s beaked whale (Mesoplodon mirus) is a poorly known member of the family Ziphiidae, second largest family of cetaceans (which includes whales, dolphins and porpoises). Little is known about its distribution, abundance and calving rate. However, an international team of researchers has now obtained the first images of a calf along with the first underwater video of this rare whale, and also described a new coloration for the species.

True’s beaked whales (Mesoplodon mirus). Image credit: Roland Edler, Duisburg Zoo.

Although True’s beaked whales occur in the North Atlantic and in the Southern Hemisphere, there is a surprisingly large gap in their distribution between these regions. This gap may be real, or might be an artifact of the lack of data.

In a paper published this month in the journal PeerJ, a research team led by Dr. Natacha Aguilar de Soto of the University of St. Andrews and the University of La Laguna show that the Azores, and to a lesser extent the Canary Islands, may actually be a hot-spot for the study of True’s beaked whales.

The steep bathymetry of these oceanic archipelagos means that deep waters occur close to shore, facilitating studies of deep-water dwelling species.

Dr. Aguilar de Soto and her colleagues gathered stranding data and sightings performed by other scientists, whale watch companies and educational teams in Azores and Canary Islands.

These data include the first underwater video of True’s beaked whales and photos of a very young calf, as well as a stranded whale confirmed genetically as a True’s beaked whale but showing a coloration pattern never observed before in this species.

These data are highly valuable to learn more about recognizing True’s beaked whales at sea, something which is essential for studies of their distribution and abundance.

It is also the first time that this species has been identified with molecular data in this region, allowing definitive links between coloration and species to be made.

“The recording of several observations of this species in deep but relatively coastal waters off the Azores and the Canary Islands suggests that these archipelagos may be unique locations to study the behavior of the enigmatic True’s beaked whale,” Dr. Aguilar de Soto and co-authors said.

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N. Aguilar de Soto et al. 2017. True’s beaked whale (Mesoplodon mirus) in Macaronesia. PeerJ 5: e3059; doi: 10.7717/peerj.3059