The United Nations should help to protect little-known corals in deep, cold waters along with tropical cousins like Australia's Great Barrier Reef, Norway's Environment Minister said on Wednesday.
Boerge Brende, who also heads the UN Commission on Sustainable Development, said trawlers' nets were gradually bulldozing coral reefs in cold seas and so wrecking spawning grounds for fish from the Arctic to the Antarctic.
"We want the UN to take an interest in cold water reefs and not just in the tropical reefs," Brende told Reuters after receiving an award from the WWF environmental group for what it called Oslo's global lead in protecting cold water corals.
Brende said he wanted the UN commission, which is following up on an Earth Summit in Johannesburg last year, to consider measures to protect cold water corals and so maintain them as habitats for dozens of other marine species.
Norway has the world's biggest known reef of so-called lophelia coral - about 45 km (28 miles) long and three wide in the Norwegian Sea. Corals are tiny animals - ranging in colour from pink to white - that build reefs over thousands of years.
"Forty percent of warm water reefs have been destroyed and perhaps 30 percent of cold water reefs in Norway have been damaged by trawling and other activities," Brende said.
In some areas off Norway, trawlers have been banned from dragging nets along the seabed in a measure the WWF says should be mirrored by other nations in cold climates. Oil drilling and pipelines are also among threats to the reefs.
Australia said last week it would ban fishermen from about one third of the 2,000 km (1,240 mile) long Great Barrier Reef to protect the world's largest living structure.
Deep water corals thrive in waters from 200 metres (650 ft) to 2,000 metres deep - unlike tropical corals, they do not depend on sunlight. Scores have been found in recent years, but researchers say large tracts of the seabed are uncharted.
"We're going to use the Norwegian example in other parts of the world to show what can be done," said Simon Cripps, director of WWF's Endangered Seas Programme.
Tomas Lundalv, of Sweden's Tjarno Marine Biological Laboratory, said oil companies might be interested in mapping corals. He said there were hints that corals thrived in areas where natural gas seeped up from subsea reservoirs.