Cetaceans are an order of aquatic mammals that includes whales and dolphins. They are exceptional creatures. Equipped with lungs, they can remain under water for over an hour and swim to depths of 6,500 feet (2,000 meters). Most use a sophisticated system comparable to sonar for orientation. Many migrate across the globe each year. The blue whale is the largest animal that has ever lived on Earth, weighing up to 190 tons.
Whales and dolphins are unusually intelligent, the only animals to compare with primates in this respect. They form hierarchical social groups similar in size and organization to those of great apes—groups which depend, among other things, on sophisticated systems of communication. Their nervous system is similar to our own—a fact often invoked to denounce the particularly cruel methods by which whales are hunted. Wounds inflicted by harpoons are rarely fatal in themselves but lead to a protracted and painful death from blood loss.
The intergovernmental body that regulates whaling is known as the International Whaling Commission. The Commission adopted a moratorium on commercial whaling in 1986ó which is still in force—and created a whale sanctuary in the Southern Ocean in 1994. But several member countries of the IWC are demanding a partial reintroduction of whaling, in addition to an extension of the existing exceptions. This has prompted a great deal of angry debate.
Whaling is by no means the only danger faced by cetaceans, of which some thirty or so species (almost half) are at risk. Fishing nets trap and drown tens of thousands of them, and although special nets have been designed to enable the creatures to break free, these are more expensive than standard nets and not widely used. Chemical pollution is also causing significant damage: being at the top of the food chain, whales and dolphins are particularly susceptible to increased contamination. Sound pollution— especially ultra-powerful military sonar—also disorientates them. And finally there is the problem of collisions with shipping vessels, which wreak havoc among the larger species.