Remember the London whale? Remember the fuss? Just under seven years ago, in January 2006, a poor leviathan, 16ft long and weighing seven tonnes, was found swimming in the Thames, right in the heart of the capital. I mean, surging right there past the Thames Barrier, and Tower Bridge, and the London Eye and the Houses of Parliament, followed by excited crowds, until it got stuck in Chelsea. A rescue was bravely attempted but the whale died, probably from stress aggravated by starvation, as it was being transported back to sea, amidst national anguish.

The irony was, it was doing the right thing – it was swimming westwards. It had almost certainly taken a wrong left turn in the straits of Dover and ended up in the North Sea and eventually, the Thames estuary, whereas it should have been in the deep waters of the Atlantic where it could find the squid on which to feed; but unfortunately, the route it chose (or was stuck with) meant it would have had to get back to the Atlantic via Maidenhead, Reading and Cirencester.

I’m sure you do remember it; but there’s one thing I bet you can’t remember, and that is, what species of whale was it? To put you out of your misery, I will tell you that it was a northern bottlenose whale, a species from the least known group of the cetaceans – the whales and dolphins – which are the beaked whales.

Leagues under the sea

We all know the baleen whales, which have baleen plates, or giant filters in their mouths to trap plankton, because these 15 or so species include the world’s biggest animals, such as the blue whale and the humpback, and around British coasts, the minke whale. And we all know the toothed whales, because this group of 50-plus species includes all the dolphins and porpoises, and other very familiar creatures such as the sperm whale – Moby Dick in Melville’s epic – and the orca or killer whale, and the white whale, the beluga. 

But the beaked whales are largely a mystery, to zoologists as well as to general wildlife enthusiasts. Cuvier’s beaked whale, Gervais’ beaked whale, Blainville’s beaked whale, Sowerby’s beaked whale – ever heard of any of them? Top of the class if you have. This group of about 20 species is undoubtedly the least-known of all marine mammals, and very likely the least known large mammals on earth, because they spend much of their time at tremendous depths in the ocean, feeding on squid, and are rarely encountered on the surface.

Remains

I have always been fascinated by them, so I was even more fascinated to learn that the rarest of them all has just been seen and described for the first time. This is the spade-toothed whale, Mesoplodon traversii, known for more than a century only from a partial jawbone found in New Zealand, and two subsequent skulls. But two years ago, a cow and a calf were stranded in New Zealand’s Bay of Plenty. They were originally identified as examples of Gray’s beaked whale; yet subsequent DNA analysis showed that mother and infant were indeed spade-toothed whales, the first complete specimens ever seen. (The finding is reported in the latest edition of the journal Current Biology.)

This is a discovery up there with the finding of the okapi in Central Africa in 1901, or with the discovery of the saola, or Vu Quang ox, in Vietnam in 1992. Those two large, hitherto unknown beasts came from the world’s deepest and most impenetrable jungles. But the deep ocean is infinitely larger than the rainforest, and even more impenetrable, who knows but there may still be great beasts left to discover?

Here’s to the spade-toothed whale. It is heartening to realise that even now, when much of the earth can be mapped on your mobile phone, some of the mystery still remains.