© Scott Baker
Scott Baker stumbled across a dead Cuvier's beaked whale on a remote stretch of beach west of Portland.
The carcass of an elusive Cuvier's beaked whale has been found stranded on a beach at Discovery Bay in Portland, in south-western Victoria.

The deep-diving mammal was discovered on a remote stretch of beach west of Warrnambool on Sunday.

The whale species is known to dive to depths of up to 3,000 metres and can spend more than two hours underwater.

Scott Baker, who came across the carcass while hiking, knew the find was significant.

"It was very exciting, they're not very commonly found," he said.

After photographing the animal, Mr Baker contacted researchers for a second opinion.

But by the time Museum Victoria expressed an interest in salvaging the carcass, it was nowhere to be found.

The museum's senior curator of mammals, Kevin Rowe, said Mr Baker discovered the dead whale five kilometres from the nearest access point.

"There were high seas at the time, so it wasn't confirmed if it was even still on the beach," he said.

"Sightings are pretty rare."

Mr Rowe said the museum did not have any complete specimens of beaked whales in their collection, so when they did wash up, he was very interested.

"There's lots of questions about the ecology and diving of these animals, what they're eating, what's happening to their food resources," he said.

"So if we had've been able to secure this animal we could have figured out things about its reproductive condition and health."

The Department of Environment, Land, Water and Planning (DELWP) said the last recorded Cuvier's stranding occurred in 2008 at Joanna in western Victoria.