Pilot whale: how many there are and what threats they face



by LORENZO CIOTTI

Pilot whale: how many there are and what threats they face

Pilot whales are among the most common and widely distributed marine mammals of the order Cetacea. These whales prefers slightly cooler waters and divides into two populations. The largest group is found in a circumpolar belt in the Southern Ocean ranging from approximately 20°S to 65°S.

It can be seen off the coasts of Chile, Argentina, South Africa, Australia and New Zealand. The population of this group is estimated at over 200,000 individuals. The second population is much smaller and inhabits the North Atlantic Ocean, ranging from South Carolina in the United States to the Azores and Morocco in the south and from Newfoundland and Greenland to Iceland and northern Norway in the north.

It is also present in the western half of the Mediterranean Sea. It is found in the temperate and tropical waters of the Indian, Atlantic and Pacific oceans. The population in the western Atlantic slightly overlaps that of G.

melas. There are 150,000 individuals in the tropical eastern Pacific Ocean. More than 30,000 animals are estimated to live in the Western Pacific, off the coast of Japan. The prospect of long-term survival for both species is well assured.

In fact, in its Red List of Threatened Species, the IUCN classifies both species as low risk; conservation dependent. Pilot whales has traditionally been hunted by whalers using the so-called driving tactic, in which many fishermen and boats surrounded a group of whales and then slowly drove them ashore, where they killed them.

This practice was common in both the 19th and 20th centuries, declining only in the 1990s. In the 1980s, about 2,500 individuals were killed in this manner each year. Currently this type of hunting, called Grindadráp, is carried out only on the Faroe Islands - where around 1000 animals are killed every year.

They has also been hunted for many centuries, mainly by Japanese whalers. In the mid-1980s the Japanese were killing 2,300 animals a year. This number dropped to 400 a year in the 1990s. Harpoon killings are still relatively common in the Lesser Antilles, Indonesia and Sri Lanka.

Since these catches are not recorded we do not know exactly how many catches are made each year and the effect they have on the local population. Both species are killed every year by the hundreds or possibly thousands along the coastline and in deep-sea nets.