A new international agreement is needed to police the exploitation of the deep ocean because of the rising threats of deep-sea mining and bottom trawling for fish , say scientists .

Speakersat asymposiumthis month(16 February)urgedthe UN to negotiateanew treatyfor the deep oceanto supplementthe UN Convention on the Law of the Sea.

The symposium took placeat the annual meeting of theAAAS (American Association for the Advancement of Science) in Chicago, United States.

“This is an opportunity for scientists to voice their concerns about mounting human impacts on the once–remote deep ocean to those who have the power in their hands to make the changes,” says Kristina Gjerde, high seaspolicyadvisorfortheInternational Union for Conservation of Nature.

The deep sea makes up about two – thirds of the world’s ocean s. It begin s at a depth of around 200 metres , both within and beyond zones of national jurisdiction.

Butdeep–sea environments arethreatened by “imminent” mining and bottom trawling for fish, saidthe scientistsat the meeting.

“We’re calling for a new treaty to sew the gaps in international law that don’tcurrentlyincludebiodiversity,conservation, marine genetic resources, capacity development andtechnologytransferforareas beyond national jurisdiction,” says Gjerde.

The UN-sanctioned International Seabed Authority (ISA) was established in 1994 to regulatemineral extraction fromthe deep seabed outside national zones of jurisdiction.The ISA, based in Jamaica, has so far approved 19mineralprospecting licences in the deep ocean around the world for companies and government bodies, includingChina and India, as well asthose sponsored bythePacific island nations of Kiribati, NauruandTonga[See map].TheCook Islands have also applied to exploredeep-sea mining opportunities.

But the ISA does notregulatemarine genetic resources, which could be valuable to the medical and pharmaceutical sectors, or biodiversity conservation,says Lisa Levin, director of the Center for Marine Biodiversity & Conservation at the Scripps Institution of Oceanography, United States.

“The problem is that the ISA’s mandate is to facilitate the extraction of minerals. They don’t have a mandate to identify which parts of the sea floor are most critical to ecosystem health in the ocean,” saysLinwood Pendleton,senior scholarinthe Ocean and Coastal Policy Program at Duke University, United States.

Thenew treatywould ensure thatfinancialgains made from marine genetic resources are shared betweenallnations,and that new mechanismsare developedto transfer marine technology and developcapacityin this field, says Gjerde.

Significant deep sea resources are often found within the deep seas of the developing world, often within the nations’ exclusive economic zones [that stretch up to 200 nautical miles from their shore] of those countries, says Levin.

“Yet those countries often don’t have the necessary expertise or technology to explore the deep seabed. So they often rely on countries that do have the technology and expertise,” she says.

“It’s very important that we do a lot of capacity building, information sharing and transfer of expertise so that those countries are able to manage their own deep ocean resources.”

The scientistsat the meetingalsowarnedthat extractingminerals and precious metals from the deep sea couldcausecatastrophic long-termdamage tomarine ecologyunlessmanaged carefully.

New technology, dwindling land-based resources and high commodity prices mean that deep-sea mining is not only feasible, but imminent, says Pendleton.

“Precaution is essential,” saysGjerde.“This means rules should be in place before mining begins, including measures such as environmental impact assessments, comprehensive systems of marine protected areas and the mechanisms for monitoring and controlling impacts.”

She adds: “It is important to set and maintain common standards so that a few unscrupulous operators can’t take advantage of countries with weak legal systems, causing irreparable harm in return for very short–term gain.”

New mining ventures are underwayoff variousPacificislands and off the African coast, as well as on the international seab爱德一个reathat liesoutsidenations’jurisdiction,says Gjerde.

Canad i a n company Nautilus Minerals had planned to mine hydrothermal vents in Papua New Guinea , but this has been delayed, says Levin.

And the Namibian government is considering leasing the deep sea bottom in its national waters for phosphate mining,althoughlast September it placedan 18-month moratorium on all mining decisions, whileitgathersnew information, she adds.

“Because no mining has happened yet[anywhere in the deep sea], there’s time to put some majorenvironmentalmanagement in place,” she tellsSciDev.Net.

The key is to identify places where mineral wealth is high and ecological impacts are lowand target mining there, says Pendleton.

Deep-sea trawling for fish has already had terrible long-lasting impacts on the deep sea, says Gjerde.

The deep sea fish populations are quickly depleted because the fish aggregate, which makes them easy to catch, and they are slow growing, living over one hundred years, says Levin.

One-fifth of the world’s continental margins, an area the size of the United States and Canada combined, have already been trawled, she adds.