(CNN) The ocean covers more than 70% of our planet, a total of 139 million square miles. An initiative launched on Tuesday aims to protect 5% of it in the next five years.
That might sound like a drop, but at 7 million square miles, it's a larger area than the entire continent of South America. And considering that by some estimates less than 3% of global ocean is currently fully protected, both the target and the timeframe is ambitious.
The initiative, named the Blue Nature Alliance, has "a very audacious goal," says M. Sanjayan, CEO of Conservation International, one of the organizations leading the program. "It's probably the largest single conservation effort in terms of size and speed."
Oceans are integral to human survival, helping to regulate rainfall, weather, and even oxygen levels in the air. But increasingly they are under threat from climate change, pollution, and overfishing.
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A collaboration between Conservation International and other environmental and social non-profits -- including The Pew Charitable Trusts, the Global Environment Facility, Minderoo Foundation, and the Rob and Melani Walton Foundation -- the Blue Nature Alliance has raised $125 million to protect the ocean from these threats.
The Alliance has started by targeting seven ocean locations around Antarctica, Fiji, Canada, the Seychelles, Palau, the Western Indian Ocean and Tristan da Cunha, an island in the South Atlantic Ocean. Those areas cover over 2.5 million square miles in total -- more than a third of the overall goal.
It says it will begin by focusing on conservation in these areas, working with local communities and national leaders to establish new marine protected areas (MPAs), and improve the management of existing ones.
Sanjayan says an MPA should be somewhere where "there is no large-scale commercial fishing, there's a management plan, there's a monitoring plan, and there's inclusion of local communities."
According to the Marine Protection Atlas, around 7% of global oceans have been designated as protected areas, but only 2.7% is considered "fully protected."
"Some of them are just in name only," Sanjayan tells CNN, adding that the Blue Nature Alliance wants to fully implement and maintain these zones.
In Antarctica's Southern Ocean, where the Alliance wants to protect an area double the size of Indonesia, its efforts are focused on keeping out industrial fishing and preserving the species that are key to the food chain there, such as leopard seals, penguins and krill.
In the Fiji Lau Seascape, an area on the eastern side of the Fiji archipelago, the Alliance is working closely with the government to legally assign new protected areas and place limits on fishing and tourism, which it says will support the region's indigenous population by protecting local culture and food supplies.
While Sanjayan admits that enforcing these measures will be a challenge, he believes that technological advances will help; improvements in satellite technology have made it easier to spot illegal fishing, while the support of local communities will help to ensure the maintenance of protected areas.
"If people in the country understand why (the ocean) is important, they're much more likely to want to protect it," he says.
Efforts from the Blue Nature Alliance will contribute towards a global conservation initiative to protect at least 30% of the ocean by 2030, a goal expected to be ratified at the United Nations Biodiversity Conference later this year. Research suggests that that this level of protection is required to maintain biodiversity and marine ecosystems.
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In a press release, former UN climate chief Christiana Figueres welcomed the launch of the Alliance.
"As greenhouse gas emissions continue to threaten our world, restoring and maintaining the health of our ocean through efforts such as the Blue Nature Alliance can help to preserve biodiversity and buffer the planet against the devastating impacts of climate change," she said.