Mammals
Arnoux's Beaked Whale
Berardius arnuxii · also called southern four-toothed whale
Diving to extreme depths in some of the coldest waters on Earth, Arnoux’s beaked whale remains one of the least studied whale species alive, a southern counterpart to Baird’s beaked whale that spends most of its life far beyond the reach of easy observation.
Overview
Arnoux’s beaked whale, Berardius arnuxii, is a Data Deficient marine mammal native to ocean and polar habitat across circumpolar Antarctic and subantarctic waters of the Southern Ocean. Its extraordinarily deep diving ability, close relationship to Baird’s beaked whale, and status among the least understood large whales make it one of the more mysterious marine mammals found anywhere in Antarctic waters.
A whale that keeps its secrets
Spending much of its life at depths far beyond where researchers can easily follow, Arnoux’s beaked whale has resisted the kind of sustained study that has revealed so much about other whale species, leaving basic questions about its population and behaviour still largely unanswered.
Status
Data Deficient, with population size and trends remaining poorly documented across its remote circumpolar Antarctic range, reflecting the general difficulty of studying deep-diving beaked whale species.
Arnoux's Beaked Whale: common questions
How is Arnoux's beaked whale related to Baird's beaked whale?
This species is the Southern Hemisphere counterpart to Baird's beaked whale, closely related but found in cold circumpolar waters around Antarctica rather than the North Pacific range of its relative.
How deep can Arnoux's beaked whale dive?
This species is capable of diving to extreme depths in search of squid and deep-water fish, among the deepest-diving whale species known to researchers.
Why is so little known about Arnoux's beaked whale?
This species remains one of the least studied large whale species, since it dives to great depths in remote Antarctic waters, making direct observation and population study extremely difficult.
Why is Arnoux's beaked whale classified as Data Deficient?
This species lacks the detailed population data needed for a more precise conservation assessment, reflecting how difficult it is to study a deep-diving whale across such a remote circumpolar range.