Whales, dolphins and porpoises threatened by over-fishing

05 February 2010 | News story

For many years, fisheries activities have increasingly placed pressure on the world’s fish stocks, but a recent scientific report, launched this week by the Convention on the Conservation of Migratory Species of Wild Animals (UNEP/CMS), outlines the gravity of the consequences for another group of animals: the toothed whales.

Data from the IUCN Red List of Threatened Species™ supports the report, which reveals that whales, dolphins and porpoises are currently suffering dramatic declines as a result of becoming entangled, and consequently drowned, in the astonishing variety of fishing equipment in use throughout our oceans, including trawls and longlines. The report states that 86% of all toothed whale species are at major risk of becoming accidentally trapped as by-catch, and that 13 species of toothed whale are also struggling to cope with dwindling food supplies as a result of over-fishing.

Toothed whales are found in a wide range of marine and freshwater habitats, from the freezing waters of the Arctic to the warmth of the tropics, including large river systems such as the Amazon and Ganges. Many populations have been hunted to the brink of extinction; 50 species continue to be hunted, often at unsustainable levels, and current additional threats include physical harm through ship strikes or ingestion of plastic debris, chemical pollution, noise disturbance, and habitat degradation.

Six toothed whale species are listed on Appendix I of the Convention, meaning they are in danger of extinction, a fate feared to have been suffered by the Baiji River Dolphin, and something which UNEP/CMS would like to prevent, according to Elizabeth Mrema, Executive Secretary of UNEP/CMS.

“During the International Year of Biodiversity, the Convention on Migratory Species continues to address major threats such as by-catch, ship strikes, ocean noise impacts and climate change to safeguard these charismatic marine mammals. Governments need to enhance their efforts towards implementing targeted action plans under the Convention,” she said in a statement to the press.

The detailed information on the distribution, behaviour and migration of toothed whales, which has been compiled for the report, will play a key role in facilitating the development and implementation of these action plans, with a view to halting the decline in population numbers. To accompany the report, a poster has been produced which for the first time clearly displays all 72 toothed whale species according to their conservation status as defined on the IUCN Red List, visually highlighting the true severity of the situation.

To find out more information, please visit: www.cms.int