According to estimates, more than 1 million square kilometers of ocean depths less than 200 meters are being plowed by trawlers, and oil, gas and mineral extraction will expand into deeper and deeper waters over the next decade (see go.nature .com) / BRHBL). At risk are ecosystems that contribute to ocean health and productivity, which challenge our notions of extremes at which life can exist (such as hydrothermal vents), and which are habitats and nurseries for fisheries ( For example seamount).
Our knowledge of deep-sea biodiversity only points to thousands of undiscovered creatures and their benefits. Some threatened species, such as cold-water coral, live for hundreds or even thousands of years; The habitat, which consists of rock concrete called manganese nodule beds, may take millennia to build.
We call for the establishment of formal governance structures and funds by 2020 to build a network of deep-sea reserves that sustain and restore biodiversity and function in this vast and important biome. To support these efforts, a global strategy should be drawn up under the auspices of national governments and an international body. For areas that are outside national jurisdiction, the International Sea Level Authority (ISA) is best suited for this task.
Cost and benefit
Deep-sea restoration experiments have already begun. Cold water corals from the Northeast Atlantic survive and grow in laboratories and experimental re-introduction to the ocean floor has proven successful, with 76% of corals alive after three years. Efforts are on in the United Kingdom to develop ‘Coralbots’, a swarm of autonomous underwater vehicles to transplant and monitor deep-sea coral fragments to address fishing losses.
But the potential effectiveness of large-scale restoration is unknown, and the precedents are not promising: after nearly four decades of restoration, freshwater and coastal ecosystems still have not recovered their full biodiversity and functionality.
Repairing damage to deep-sea ecosystems and enhancing their recovery will be two to three orders of magnitude more expensive than shallow ones. For example, it could cost US$75 million to restore a hectare of trapped sea floor in the Darwin Mounds hummocks at a depth of one kilometer in the Rockall Trough of the northeastern Atlantic.
This is a price that many feel is worth paying. As well as oil, gas, mineral and biomedical resources, deep-sea ecosystems have other important functions, including roles in gas and climate regulation, and waste absorption and detoxification.
A 2007 study7 showed that the public in Ireland is willing to pay up to €10 (US$14) per person to protect deep-sea corals from being trapped so that the corals are essential for the biomedical industry, essential fish habitat and carbon sinks. to provide raw materials.
Visitors and residents in the Azores, an Atlantic archipelago about 1,500 kilometers west of Portugal, are expected to pay €405-605 per person to prevent a 10–25% reduction in marine species richness in open waters, including the deep sea. expressed desire. In Scotland, Survey 6 respondents were willing to pay £70 (US$115) to £77 each to promote maximum deep-sea biodiversity conservation and develop new medicinal products from deep-sea species.
A global strategy
A key feature of the global strategy to protect and restore the deep sea should be the ‘polluter pay’ principle. That is, the stakeholders most responsible for the loss should fund deep-sea ecosystem reserves, research and restoration. These entities are likely to include mining, oil and gas, transportation and fishing companies.
However, the implementation of this strategy will depend on whether the deep sea is within or outside national borders. For areas within national jurisdiction, the responsibility for restoration, protection and determination of liability rests with individual states. Governance in areas outside national jurisdiction, where most is located in the deep sea, is currently divided according to regional activities – mainly fishing, shipping and mining.
As a universal authority to consider ecosystem conservation, costs and benefits in international waters does not yet exist, discussions are underway to add a biodiversity-conservation agreement to the United Nations Convention on the Law of the Sea (UNCLOS), in which The decision will be in late 2015. Such development is a necessary first step to protect the deep sea.
A key component of the 2015 United Nations General Assembly decision should be to either develop a new body to protect deep-sea biodiversity, or expand the ISA’s mandate beyond mining to allow habitats to be regulated by a wide range of commercial industrial activities. chain can be saved.
An important role of the Convention on Biodiversity (CBD) is to provide scientific and technical advice to states and relevant authorities, so close cooperation between the CBD and the ISA is established even during such negotiations.