Marine Conservation Biology Institute Marine Conservation Biology Institute
Marine Conservation Biology Institute
Protecting Marine Ecosystems

Deep-Sea Coral Scientist Statement

Rockfish in a deep-sea coral colony (Photo: V. O'Connell, ADF&G)  

In an effort to bring the deep-sea coral and sponge ecosystems to the forefront of the minds of decision makers, MCBI organized the Scientists' Statement on Protecting the World's Deep-sea Coral and Sponge Ecosystems.

Garnering signatures from 1,136 scientists from 69 countries in 2004, this historic proclamation signifies unprecedented concern by experts in marine sciences and conservation biology, including the world's foremost biologists. The consensus statement was released at the AAAS annual meeting on February 15, 2004, calling for governments and the United Nations to protect imperiled deep-sea coral and sponge ecosystems.

The statement was later reopened to signing, and the number of signers increased to 1,452 in 2006. These signatures were submitted to the United Nations to support coral and sponge conservation in international waters.

View the statement, the 1452 signatures [PDF] and related media coverage.


As marine scientists and conservation biologists, we are profoundly concerned that human activities, particularly bottom trawling, are causing unprecedented damage to the deep-sea coral and sponge communities on continental plateaus and slopes, and on seamounts and mid-ocean ridges.

Shallow-water coral reefs are sometimes called "the rainforests of the sea" for their extraordinary biological diversity, perhaps the highest anywhere on Earth. However, until quite recently, few people — even marine scientists — knew that the majority of coral species live in colder, darker depths, or that some of these form coral reefs and forests similar to those of shallow waters in appearance, species richness and importance to fisheries. Lophelia coral reefs in cold waters of the Northeast Atlantic have over 1,300 species of invertebrates, and over 850 species of macro- and megafauna were recently found on seamounts in the Tasman and Coral Seas, as many as in a shallow-water coral reef. Because seamounts are essentially undersea islands, many seamount species are endemics — species that occur nowhere else — and are therefore exceptionally vulnerable to extinction. Moreover, marine scientists have observed large numbers of commercially important but increasingly uncommon groupers and redfish among the sheltering structures of deep-sea coral reefs. Finally, because of their longevity, some deep-sea corals can serve as archives of past climate conditions that are important to understanding global climate change. In short, based on current knowledge, deep-sea coral and sponge communities appear to be as important to the biodiversity of the oceans and the sustainability of fisheries as their analogues in shallow tropical seas.

In recent years scientists have discovered deep-sea corals and/or coral reefs in Japan, Tasmania, New Zealand, Alaska, California, Nova Scotia, Maine, North Carolina, Florida, Colombia, Brazil, Norway, Sweden, UK, Ireland and Mauritania. Because research submarines and remotely operated vehicles suitable for studying the deep sea are few and expensive to operate, scientific investigation of these remarkable communities is in its very early stages. But it is increasingly clear that deep-sea corals usually inhabit places where natural disturbance is rare, and where growth and reproduction appear to be exceedingly slow. Deep-sea corals and sponges may live for centuries, making them and the myriad species that depend on them extremely slow to recover from disturbance.

Unfortunately, just as scientists have begun to understand the diversity, importance and vulnerability of deep-sea coral forests and reefs, humans have developed technologies that profoundly disturb them. There is reason for concern about deep-sea oil and gas development, deep-sea mining and global warming, but, at present, the greatest human threat to coral and sponge communities is commercial fishing, especially bottom trawling. Trawlers are vessels that drag large, heavily weighted nets across the seafloor to catch fishes and shrimps. Scientific studies around the world have shown that trawling is devastating to corals and sponges. As trawlers become more technologically sophisticated, and as fishes disappear from shallower areas, trawling is increasingly occurring at depths exceeding 1,000 meters.

It is not too late to save most of the world's deep-sea coral and sponge ecosystems. We commend nations including Australia, New Zealand, Canada and Norway, which have already taken initial steps towards protecting some coral and sponge ecosystems under their jurisdiction. We urge the United Nations and appropriate international bodies to establish a moratorium on bottom trawling on the High Seas. Similarly, we urge individual nations and states to ban bottom trawling to protect deep-sea ecosystems wherever coral forests and reefs are known to occur within their Exclusive Economic Zones. We urge them to prohibit roller and rockhopper trawls and any similar technologies that allow fishermen to trawl on the rough bottoms where deep-sea coral and sponge communities are most likely to occur. We urge them to support research and mapping of vulnerable deep-sea coral and sponge communities. And we urge them to establish effective, representative networks of marine protected areas that include deep-sea coral and sponge communities.

Related Media Coverage

1,000 Scientists urge halt to deep-sea bottom trawling. (2004, February 16). Terra Daily.

1,000 scientists urge halt to deep-sea bottom trawling. (2004, February 16). Yahoo News.

1,000 Scientists urge halt to deep-sea bottom trawling. (2004, February 16).

Action needed to save corals. (2004, February 16). CBBC Newsround.

Amos, J. (2004, February 16). Deep-sea corals protection call. BBC News World Edition.

Black, R. (2004, February 16). The statement is signed by scientists from seventy countries. [Audio clip.] BBC News.

Call for protection of endangered deep-sea corals. (2004, February 17). Borneo Bulletin. (Brunei).

Concerns raised over fishing practice. (2004, February 16). RTÉ News. (Ireland).

Governments urged to protect the deep sea. (2004, February 17). Scoop. (New Zealand).

Halt to deep seabed trawling urged. (2004, February 16). IRIB News: Islamic Republic of Iran Broadcasting.

Human actions threaten all ocean life, scientists warn. (2004, February 16). Environment News Service.

Hunt, E. (2004, February 17). Scientists call for bottom trawl halt: Biologically rich seamounts and sponge colonies threatened by fishing practice. TidePool.

Pickrell, J. (2004, February 19). Trawlers Destroying Deep-Sea Reefs, Scientists Say. National Geographic News.

Scientists call for urgent action to protect deep-sea coral reefs. (2004, February). Talk:

Scientists urge deep-sea action. (2004, February 17). Green Consumer Guide. (United Kingdom).

Stop deep-sea trawls to protect coral, scientists urge. (2004, February 16). CBC News.

Tam, S. (2004, February 15). Banning bottom trawling. The Star. (Malaysia).




Download the Scientists' Statement on Protecting the World's Deep-sea Coral and Sponge Ecosystems full text [PDF] and the list of its 1452 signatures [PDF].