Blues whales facing threat from cargo ships (Photo : REUTERS/Joshua Barton)
Blue whales have been found to lack the navigational skills required to get off the path of ships quickly, new research has revealed.
Scientists involved with conservation of whales attributed the stagnant population of the once endangered species to their frequent encounter with ships, many of which prove to be fatal.
"It's not part of their evolutionary history to have cargo ships killing them, so they haven't developed behavioral responses to this threat," said Jeremy Goldbogen, an assistant professor of biology at Stanford's Hopkins Marine Station who is also involved in the study.
The whales can grow to 30 meters in length and weigh over 210 tonnes. Researchers also stated they need to be at least 30 meters beneath the surface to avoid being sucked by the ship's propellers, stated Geeek.
The whales are also fast swimmers and can detect ships far away though it is their immediate response during close encounters with a ship that has left the researchers baffled. Instead of diving head first into the deep or dashing away, they tend to play dead and dive horizontally. This enables them to sink at the rate of just half a meter per second, which is too slow to avoid a direct contact with a ship in close proximity.
Another reason to explain the whales' behaviour is that they have never had any predators for millions of years. They have never evolved any defensive tactics as such, mentioned Discovery.
Precautionary measures adopted to prevent the whales from coming in contact with ships include re-routing the shipping lanes from whales' breeding grounds or to impose speed limits for ships in areas frequented by whales.
