Environment Minister Nick Smith will be leading New Zealand's delegation to a major international conference about the state of the world's oceans.
The Our Oceans Conference in the Chilean city Valparaiso hopes to improve marine management.
"Oceans make up 72 per cent of the world, but only two per cent is in protected areas. The populations of marine life like fish and seabirds have halved over the past 40 years," Dr Smith said.
"The biggest problems are in the high seas beyond individual countries jurisdictions, making up about 70 per cent of the oceans, where we need strengthened institutions and rules to ensure the sustainability of fishing stocks and improved protection of marine life."
There'll be more than 100 other countries represented at the conference.
Dr Smith says New Zealand's ambition is to be a leader in ocean management.
"Our quota management system is recognised as being world's best practice, and we have more certified sustainable fishing stocks than any other country."
At the United Nations last week, Prime Minister John Key announced the creation of a 620,000 sq km ocean sanctuary in the Kermadec region.
Dr Smith will also be holding bilateral meetings in Chile on issues like earthquake resilience, air and water quality and protected areas management.