A new theory that may solve a centuries old mystery

Dec 28, 2005 13:30 GMT  ·  By

In October this year no less than 130 whales have stranded on a Tasmanian beach.

The Australian marine denied that the event was caused by their use of sonars. A. Frantzis, a zoologist from Athens University claims there is a long line of suspicious confidences relating army sonars and whale standings. Margaret Klinowska claims that whales use the Earth's magnetic field in order to guide themselves and she claims there is a connection between the areas where the magnetic field is disturbed by various geological formations and the areas where whales have stranded. Captain David Williams tried to prove a connection between marine earthquakes and whale standings. Others have tried to find connections between the existence of toxic substances and the whale stranding.

To make the long story short, there are plenty of alternative theories regarding why whales are stranding on beaches, and why there are often mass stranding.

The researchers at Australian University in Perth have analyzed the entire situation in more detail and it is possible that they have finally come up with a good theory. Shane Chambers and her collaborators have identified four main causes that lead to whale standings: the slight slopes of beaches, bad weather that creates air bubbles, the fact that whales are unfamiliar with the regions where they travel, and the whales' herd instinct.

The whales navigate mainly by using sounds: they emit sounds that in turn are reflected by objects of shores, and by detecting the reflected sounds the whales deduce the distance to a certain object. This is why when they encounter a gently sloped beach the sounds either don't reflect from them or the reflected sounds don't return to the whales. In other words, from the whales' point of view it is as if they would have anything in front of them. When they finally detect the shore, it is already too late.

The storms affect the whales' navigation because they cause air bubbles and micro-bubbles to appear, and the bubbles disrupt the signals. Such air bubbles can persist even a few days after a storm. Finally, it appears that when a whale strands on a beach the other whales follow it blindly. This often leads to mass standings.