A northern bottlenose whale that wandered deep into Loch Eli recently is one of ten that have either stranded or seen in lochs in recent years.  Researchers wonder whether noises at sea may be “herding” normally deep-water whales into the narrow lochs, where they become disoriented and perhaps also trapped by other noises.  In the recent case, whale was only persuaded to leave when a nearby fish farm had turned off its seal-scaring device. Volunteers from the Marine Life Rescue Unit then used underwater loudspeakers to play sounds of their own – including a recording of a hunting killer whale — to push the 10-metre whale back out to sea. In recent days, one such whale died after being helped toward sea, and one survived.

A northern bottlenose whale stranded in Scotland (click for London Times article)

The seal-scaring “acoustic harassment device” is “an awful siren sound — very, very loud,” said Dr Patrick Miller of the Sea Mammal Research Unit in St Andrews. “There’s quite a bit of research that says they have more effect on cetaceans than seals. It may very well be that the seal-scarer had a big effect on keeping the animal inside the loch.”

“The whales are migrating at this time of year, so we normally do see more of them, but to have so many washing up is a little strange. There’s an enormous amount of man-made noise out at sea off the northwest of Scotland, and we can’t rule out that this is what causing them to come ashore,” said Mark Simmonds, Director of Science for the Whale and Dolphin Conservation Society.

“Although we think of these as open ocean animals, for so many to come in there may be something we’re missing,” said Dr. Millar. “Maybe they’re looking for food. We just know so little about the animals it’s difficult to make strong conclusions.”