A new beaked whale species has been discovered off the coast of Hokkaido, Japan.
The species has long been known to local whalers as Kurotsuchikujira (black Baird’s beaked whale). It has been named and confirmed as Berardius minimus (B.minimus) in a collaboration between the National Museum of Nature and Science, Hokkaido University, Iwate University, and the United States National Museum of Natural History.
The Stranding Network Hokkaido research group collected six stranded unidentified beaked whales along the coasts of the Okhotsk Sea and identified them as sharing characteristics with B. bairdii (Baird’s beaked whale).
But the researchers noticed a number of distinguishable external characteristics which led them to investigate whether these beaked whales belong to a currently unclassified species.
“Just by looking at them, we could tell that they have a remarkably smaller body size, more spindle-shaped body, a shorter beak, and darker color compared to known Berardius species,” said Curator Emeritus Tadasu K. Yamada of the National Museum of Nature and Science from the research team.
Detailed cranial measurements and DNA analyses further emphasized the significant difference from the other two known species in the genus Berardius. Due to it having the smallest body size in the genus, the researchers named the new species B. minimus.
Illustrations comparing the new species B. minimus (A) and the Baird’s beaked whale (B. bairdii) (B) in the same genus. Tadasu K. Yamada et al.
These beaked whales are harder to see and inadequately understood because they prefer deep ocean waters and have a long diving capacity.
“There are still many things we don’t know about B. minimus,” said Professor Takashi F. Matsuishi, founder and manager of research group. “We still don’t know what adult females look like, and there are still many questions related to species distribution, for example.
“We hope to continue expanding what we know about B. minimus.”
Image source: Hokkaido University
