Rolling in the Deep

As a cruise ship wildlife speaker and as a member of the Ocean Wildlife Encounters (OWE) team, I get to visit some pretty remote and exotic parts of our blue planet. As the song goes "Far have I travelled and much have I seen" but there is always something you fail so see, sometimes repeatedly.

I've been lucky enough to encounter many species of beaked whales over the years, including some seldom seen and rarely photographed species, but one, close to home and not particularly scarce species, continued to elude me. Some of my cetacean buddies seemed to enjoy reminding me of this glaring chasm in my cetacean life list.

Thankfully, at 11.30am on the 15th June 2025, that gap finally closed. A cruise between Liverpool and Reykjavík crossed the prerequisite deep water, in this case the Iceland Basin, in near-perfect cetacean spotting conditions (virtually flat calm). with the sun to our stern. Two animals slightly larger than a Bottlenose Dolphin rolled slowly a few hundred metres ahead of our ship, the MS Bolette. The smallish dorsals, set well back along the body, identified them as beaked whales, but we needed to see the front end for identification purposes.

A female Sowerby's Beaked Whale emerges in the Iceland Basin © Jeff Clarke

Next time they surfaced up came two longish slender beaks, at a steep angle, and the definitive features of Sowerby's beaked Whale were confirmed. I was elated to see these wonderful creatures, as well as relieved, that I'd finally got that monkey off my back. We would have two further pods later in the day. The latter pod was particularly fascinating as it included males, females and calves. Thankfully they came close enough to our ship to enable a series of reasonable photographs to be obtained.

A Sowerby's Beaked Whale calf emerges next to its mother. © Jeff Clarke

The scientific name for Sowerby's beaked Whale is Mesoplodon bidens, a reference to the two, large, erupted teeth, one either side of the lower jaw, half-way along the beak of a male. This is somewhat misleading as the males of many species of beaked whale have two erupted teeth. However, we can forgive James Sowerby this confusion as, at the time (1800), this was the first beaked whale to be scientifically described.

An adult male Sowerby's Beaked Whale displaying erupted tooth half-way along the beak. © Jeff Clarke

An interestingly bi-coloured Sowerby's Beaked Whale. Suspected sub-adult male. © Jeff Clarke

Sowerby's Beaked Whale - Same animal as above, but no sign of erupted teeth. © Jeff Clarke

Sowerby's Beaked Whales, distinctively scarred adult male in foreground. © Jeff Clarke

Just to add a little further confusion, Sowerby's beaked Whale is also sometimes referred to as the North Atlantic Beaked Whale and also the North Sea Beaked Whale. It certainly is not common in the shallow North Sea, it is a deepwater species, when they get into shallow seas they tend to be lost, or ill, or both and as a result frequently strand and die. Given that most encounters with Sowerby's beaked Whale are the result of strandings, with a concentration of them on North Sea coasts, then this latter name starts to become more understandable.

Like most beaked whale species Sowerby's is a consumer of squid, however unlike many other species it is also a significant consumer of mesopelagic and benthopelagic fish and its highly mobile foraging strategy reflects this food preference.

Sowerby's Beaked Whale adult male - same animal as above © Jeff Clarke

As with most beaked whales the mature males are decorated in long raking scars; a direct result of contests with other males. Hence the erupted teeth. The females too can be scarred but these tend to be small and circular, a result of encounters with Cookie Cutter Sharks and Sea Lampreys. We could clearly see such scars on the animals we observed halfway between the UK an Iceland. This part of the North Atlantic is cool-temperate and Cookie Cutter sharks are not present here. Internet searches reveal a number of photographs depicting Sowerby's Beaked Whales displaying Cookie Cutter shark bites, this strongly suggests that Sowerby's beaked Whales must make significant seasonal shifts in latitude, thus bringing them into the realm of the Cookie Cutter Shark.

Sowerby's Beaked Whale female displaying suspected Cookie Cutter Shark bite scars. Iceland Basin © Jeff Clarke

Researchers suggest Sowerby's gets as far south as 33 degrees north of the equator. But the Cookie Cutter Shark is only known to get as far north as 22 degrees north. That's 11 degrees of seperation. Clearly something doesn't add up, but it's a perfect example of how limited our understanding of the ocean and its inhabitants is. Even cetaceans upto 5m in length, largely remain a mystery.

What a thrill and delight to finally catch up with this North Atlantic beakie and to see them so well. Fingers crossed they'll make a more regular appearance on my cetacean sightings list from now on.