The sperm whale has made a stunning return to the Mediterranean after finding sanctuary off Sicily, Italian marine biologists have discovered after a chance sounding by a nuclear physics lab called NEMO.
"This is great, great news," said Silvio Greco of the government's marine research institute.
"We thought these mammals had been wiped out by drift nets. Instead, the herds appear to have been coming back in remarkable numbers".
Acoustics experts from the University of Pavia were called in two years ago when NEMO (the NEutrino Mediterranean Observatory) started picking up strange sounds on its underwater particle detector off Catania, Sicily.
They quickly recognised the characteristic 'clicks' of sperm whales talking to each other at great depths.
"From the rate of soundings, we realised there had to be hundreds of them," said Gianni Pavan of Pavia University's Bioacoustics Lab.
"They've found a paradise down there".
The sperm whale, the world's biggest predator, inhabits most of the world's oceans but sightings in the Mediterranean have grown increasingly rare in recent years.
Two years ago the International Fund for Animal Welfare, a leading marine conservation group, said "sperm whales were once considered to be quite abundant in some parts of the Mediterranean but large herds are unheard of today."
