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Improving the health of the ocean

Marine reserves

Simon Reddy and Johnny Briggs of the Pew Trusts stress the importance of marine reserves that are both large and highly protected

Life on Earth depends upon the ocean, which provides half the oxygen we breathe and is the primary source of animal protein for more than 2 billion people.

But those benefits are in jeopardy. Overfishing has pushed 90 per cent of the world’s fish stocks to fully exploited or overexploited status. The populations of some large predatory species in the ocean – sharks, tuna, swordfish, marlin, grouper, cod and halibut, for example – have been reduced to just 10 per cent of historic levels. Meanwhile, warming seas have driven some species toward the high latitudes, where they now compete with native fauna for food.

The conservation imperative

Very large marine protected area (each >100,000 km2)

Photo: MPAtlas.Org / Marine Conservation Institute. CC-AS-A4.0Int.

Scientists say that one effective way to slow the oceans’ decline is to establish and enforce highly protected marine reserves, in which fishing and all extractive industries are banned. By conserving and enhancing biodiversity, such reserves help the ocean provide the benefits people have come to rely on – including a steady supply of fish, which is critical for communities around the world but especially for traditional cultures closely linked to the sea. The evidence also increasingly shows that marine reserves help ocean ecosystems build resilience against the impacts of climate change or increases in temperature.

Because individual countries have control over natural resources to a distance of 200 nautical miles from their coast, governments have the right to designate marine reserves in these waters. Yet despite the scientific evidence supporting the benefits of marine reserves, governments around the world have been slow to protect ocean areas, and the designation of large marine reserves is playing catch-up with conservation on land. While approximately 15 per cent of the global land area is protected, only 3 per cent of the ocean is safeguarded, and in roughly half of that area commercial fishing is still allowed. Although some governments have committed to creating new reserves and the United Nations has set a Sustainable Development Goal for safeguarding 10 per cent of the ocean by 2020, more action is needed. The scientific community recommends that 30 per cent of the seas must be protected to support ecosystem recovery and sustainable fisheries into the future, a goal adopted by IUCN (the International Union for Conservation of Nature) in 2016.

A crucial barrier to securing protection for 30 per cent of our oceans is that two-thirds of the ocean lies in areas beyond national jurisdiction, the high seas. To set aside as reserves even small areas of the high seas would require international agreement, which has proven difficult to achieve – although the UN is making progress on a treaty that could lead to the creation of high seas reserves. A final factor that has limited ocean protections is the misconception that large, isolated marine reserves cannot be adequately monitored and enforced.

Good news from the UK

Now for the good news. More of the ocean has been protected in the past two years than during any other period in history, continuing a trend started more than a decade ago. The Pew Trusts has played a key role in these advancements. From 2006 through 2016, Pew and its partners helped secure commitments to protect 6.3 million square kilometres of ocean – an area 26 times the size of the United Kingdom.

To build on this momentum, Pew and the Bertarelli Foundation have forged a new partnership – the Pew Bertarelli Ocean Legacy Project – with the goal of increasing the number of large and fully protected parks in the sea. The UK, with its 14 overseas territories, is responsible for the fifth-largest area of ocean in the world – 6.8 million square kilometres, which is 30 times the size of the UK’s land area. As a nation, the UK has been an international leader in ocean conservation, having promised to protect over 60 per cent of its waters by 2020 and designate a significant portion of that territory as highly protected marine reserves. The UK’s waters feature the largest coral atoll in the world, a third of the world’s albatrosses, and a quarter of the world’s penguins – more than any other country.

Pitcairn: showing the way

A wandering albatross, Pitcairn island

A wandering albatross, Pitcairn island. Photo: Johnny Briggs / The Pew Trusts

The long-term UK pledge to create marine reserves, in partnership with the communities of its overseas territories, is part of the government’s Blue Belt policy commitment and builds on the September 2016 designation of the Pitcairn Islands Marine Reserve. The Pitcairn initiative, on which Pew worked, exemplifies how community will, cuttingedge technology, and central government leadership can coalesce to deliver a significant conservation win.

The only UK overseas territory in the Pacific Ocean, the Pitcairn archipelago consists of four islands. Its 40 residents all live on the eponymous main island. Most of these islanders descend from the mutineers who seized control of HMS Bounty in 1790. The archipelago’s key characteristic is its isolation: it sits approximately 2000 kilometres from the nearest significant urban centre, Tahiti. As a result, almost no commercial fishing activity has occurred in the surrounding waters, leaving Pitcairn’s marine environment nearly pristine, with a unique ecosystem harbouring endemic birds, turtles, and whales, and the world’s deepest known living plant, a species of coralline algae found 382 metres below the sea’s surface.

But with advances in vessel technology now allowing crews to reach every square kilometre of the ocean, and with local residents dependent on fish from coastal waters for a significant part of their diet, the Pitcairn Island Council partnered with Pew in 2011 to advocate for the closure of Pitcairn Island’s waters to all extractive activity from 12 to 200 nautical miles offshore – an area of about 830,000 square kilometres, or roughly 3.5 times the size of the UK.

Rising to the global challenge

In 2015, the UK government tentatively agreed to the closure but wanted assurance that the massive, isolated area could be effectively monitored and enforced. As our colleague Peter Horn explains (see ‘Illegal, Unreported, Unregulated’), illegal, unreported and unregulated fishing is a global challenge. But a comprehensive solution of policy, technology, markets, and leadership is turning the tide on this issue. In the case of Pitcairn, the Pew Trusts, in partnership with the UK government, undertook a one-year surveillance trial using satellites to monitor the waters of the Pitcairn Islands Marine Reserve. That trial confirmed that the technological platform Eyes on the Seas can be used to effectively monitor and enforce a large, remote marine reserve. Over the coming years, the UK government has the opportunity to maintain its position of global leadership by designating large, highly protected marine reserves in the waters of South Georgia and the South Sandwich Islands, Ascension Island, and Tristan da Cunha.

Simon Reddy directs the Pew Bertarelli Ocean Legacy Project’s work in the UK overseas territories, and Johnny Briggs is an officer with the Pew Bertarelli Ocean Legacy Project, working to create large, highly protected marine reserves in the waters of the UK overseas territories.