The impact of whaling on deep-sea biodiversity

02/04/2007 00:00:00 Whaling is threatening newly-discovered deep-sea creatures with extinction, according to research by Craig Smith of the University of Hawaii. When thedead bodies of whales sink to the ocean bottom, they create 'island' habitats for deep-sea life that can last twenty years. Biologists have discovered 28 new species that may depend exclusively on whale carcasses for sustenance. Whaling will deprive the ocean of this resource.

Smith used simple models from conservation biology to plot the impact of whaling on the extinction of deep-sea creatures that live on whale carcasses. Their results suggest that species extinctions may have happened in the North Atlantic where great whales were decimated in the 18th century. Extinction may also be occuring in the Southern Ocean, where intense whaling continued until the 1970s.

These findings highlight the need to consider the effects of whaling and other types of fishing on complete ecosystems, rather than just focussing on target species. 'The possibility that whaling has caused species extinctions at the remote deep-sea floor gives us new appreciation for the scale of human impacts on the ocean,' said Smith. 'We must recognise that the oceans consist of a group of tightly connected ecosystems – over-fishing or pollution in surface waters is bound to cause problems hundreds of metres below.'