The Mysterious Shepherd's Beaked Whale
January 27, 2012
In January 2012, news broke of the discovery of Shepherd's Beaked Whales at sea off southern Victoria (Australia). In 2006, scientists wrote in Marine Mammal Science that "Shepherd’s beaked whale [is] one of the least known cetaceans in the world".
A team of researchers from the Australian Antarctic Division accompanied by marine ecologist David Donnelly found them during a reconnaissance of the area. Donnelly is remarkably one of a small handful of people who can satisfactorily prove they've seen them in the wild before. He published a photographic account on Wildiaries in May 2008 (http://au.whales.wildiaries.com/trips/150), after a filming trip off New Zealand's North Island.
When Mark Cawardine (of the BBC series 'Last Chance to See' fame, with Stephen Fry) published the Eyewitness guide to Whales, Dolphins and Porpoises in 1995, Shepherd's Beaked Whale was illustrated mostly as an artists impression. At that time, there had been no definite sightings at sea and the only markings on beached animals tended to be obscured, as skin pigment darkened in the sun.
Unknown to them and just when they were preparing for print, a freshly dead animal was hauled onto shore by scientists at Te Papa Museum in Wellington, New Zealand. This was the first time that the true identity of this obscure whale was known. Subsequent field guides have been updated and researchers could now hope to possibly see some of these animals in their natural environment.
Apart from Donnelly's two sightings, there has been perhaps as few as one other confirmed record at sea. Shepherd's Beaked Whales belong to one of the least known but species-rich groups of whales, collectively called 'beaked' whales, for their prominent rostra.
Most beaked whales have no teeth and are thought to be suction feeders. Shepherd's are pretty unique in having rows of teeth in their upper and lower jaws … perhaps they feed on fish?
Other beaked whales forage on the sea-floor. Together, they are amongst the deepest-diving mammals on the planet. Cuvier's Beaked Whales have been tracked to 1,900 metres where most air-breathing animals would be crushed to death. A female stranded dead a few years ago on Wilson's Promontory in Victoria (Australia) (see Wildiaries http://au.whales.wildiaries.com/trips/122) contained enormous squid beaks:
"Two of the beaks are of the gothic-looking and aptly named Vampyroteuthis infernalis or vampire squid, a species that is distributed world-wide and typically occurs at depths of between about 600-1,200m and is about 13cm long.
The very large beaks (several centimetre across) are from glass squid. Glass squid are a diverse group of very gelatinous squid that include some of the largest species to occur in the world's oceans. The group includes the "colossal squid" (Mesonychoteuthis), which is thought likely to exceed the weight of the giant squid (Architeuthis). A 6 metre long specimen was hauled aboard a fishing vessel in the Antarctic Ross Sea last year. The beaks in the Cuvier's stomachs might have been from specimens some 1-2m in length."
Shepherd's Beaked Whales have stranded on beaches in southern Australia and in South America but mostly in New Zealand. This latest sighting is history in the making. It's hard to believe that in a world that's arguing over climate change, carbon pricing and who will win the next 'America's Got Talent', some of the largest animals that ever lived on Earth are still a mystery to us.
A team of researchers from the Australian Antarctic Division accompanied by marine ecologist David Donnelly found a group of Shepherd's Beaked Whales during a reconnaissance of an area off southern Victoria (Australia).
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