To conserve and sustainably use the world's oceans, seas and marine resources.

• Oceans cover three quarters of the Earth's surface, contain 97 per cent of the Earth's water, and represent 99 per cent of the living space on the planet by volume
• Over three billion people depend on marine and coastal biodiversity for their livelihoods
• Globally, the market value of marine and coastal resources and industries is estimated at $3 trillion per year or about 5 per cent of global GDP
• Oceans contain nearly 200,000 identified species, but actual numbers may lie in the millions
• Oceans absorb about 30 per cent of carbon dioxide produced by humans, buffering the impacts of global warming
• Oceans serve as the world's largest source of protein, with more than 3 billion people depending on the oceans as their primary source of protein
• Marine fisheries directly or indirectly employ over 200 million people
• Subsidies for fishing are contributing to the rapid depletion of many fish species and are preventing efforts to save and restore global fisheries and related jobs, causing ocean fisheries to generate US$ 50 billion less per year than they could
• As much as 40 per cent of the world oceans are heavily affected by human activities, including pollution, depleted fisheries, and loss of coastal habitats

Oceans provide key natural resources including food, medicines, biofuels and other products. They help with the breakdown and removal of waste and pollution, and their coastal ecosystems act as buffers to reduce damage from storms. Maintaining healthy oceans supports climate change mitigation and adaptation efforts. And have you been to the seaside? It's also a great place for tourism and recreation. Even more, Marine Protected Areas contribute to poverty reduction by increasing fish catches and income, and improving health. They also help improve gender equality, as women do much of the work at small-scale fisheries. The marine environment is also home to a stunning variety of beautiful creatures, ranging from single-celled organisms to the biggest animal ever to have lived on the Earth-the blue whale. They are also home to coral reefs, one of the most diverse ecosystems on the planet.

Increasing levels of debris in the world's oceans are having a major environmental and economic impact. Marine debris impacts biodiversity through entanglement or ingestion of debris items by organisms, which can kill them or make it impossible for them to reproduce. As far as the world's coral reefs are concerned, about 20 per cent of them have been effectively destroyed and show no prospects for recovery. About 24 per cent of the remaining reefs are under imminent risk of collapse through human pressures, and a further 26 per cent are under a longer -term threat of collapse. Furthermore, improper marine management results in overfishing. The lost economic benefits from the fisheries sector are estimated to be around US$50 billion annually. The UN Environment Programme estimates the cumulative economic impact of poor ocean management practices is at least US$200 billion per year. In the absence of mitigation measures, climate change will increase the cost of damage to the ocean by an additional US$322 billion per year by 2050.

The costs of taking action largely are offset by the long-term gains. In economic terms, the Convention on Biological Diversity suggests that scaled up actions to sustain the global ocean require a US$32 billion one-time public cost and US$21 billion dollars a year for recurring costs.

For open ocean and deep sea areas, sustainability can be achieved only through increased international cooperation to protect vulnerable habitats. Establishing comprehensive, effective and equitably managed systems of government-protected areas should be pursued to conserve biodiversity and ensure a sustainable future for the fishing industry. On a local level, we should make ocean-friendly choices when buying products or eating food derived from oceans and consume only what we need. Selecting certified products is a good place to start. Making small changes in our daily lives, like taking public transport and unplugging electronics saves energy. These actions reduce our carbon footprint, a factor that contributes to rising sea levels. We should eliminate plastic usage as much as possible and organize beach clean-ups. Most importantly, we can spread the message about how important marine life is and why we need to protect it.

The Sustainable Development Goals aim to end poverty, protect the planet, and ensure prosperity for all. As such, the 17 SDGs and its associated 169 targets do not stand alone, but are are interconnected. The key to success on one will involve tackling issues more commonly associated with another. If you are interested in supporting a cause addressing to the goal {sdg.name}, you might also be interested in the related goals No Poverty, Zero Hunger, Decent Work And Economic Growth and Life On Land.