"I work on these issues day-to-day, but to see the findings of this report in the space of a generation, it is truly stunning that we can have that level of impact in such a short period of time." Green turtles swimming in the Great Barrier Reef, Queensland. Credit:Troy Mayne Director General of WWF International Marco Lambertini described the situation as nothing short of a "crisis," in his foreword to the report by WWF and the Royal Zoological Society of London. "When I wrote the foreword to the 2014 edition of WWF's Living Planet Report, I said it was not for the faint-hearted. This edition, a deep dive into the health of marine species and the habitats on which they depend, is equally if not more sobering." Tracking 5829 populations of 1234 species, the report gave a much broader overview of ocean health than previous studies.

It highlighted the impact of commercial fish stocks and the role the private sector must play in slowing rates of overfishing, suggesting that species essential to commercial fishing and global food supply were suffering the greatest declines.For example, scrombidae, the family which includes tunas, mackerels and bonitos, suffered a 74 per cent decline between 1970 and 2010. A Jackass Penguin covered in oil from an oil spill off the coast of South Africa’s Robben Island. Credit:Martin Harvey/WWF "Overfishing, destruction of marine habitats and climate change have dire consequences for the entire human population, with the poorest communities that rely on the sea getting hit fastest and hardest," said Dermot O'Gorman, CEO of WWF Australia. He said the private sector had to carry the responsibility of ensuring sustainable practices and operations, noting Australian salmon company Tassal and retailer Coles for their commitment towards sustainability. A scale of the decline in marine life from 1970 to 2010. Credit:WWF

The supermarket giant's 2015 sustainable sourcing policy for home brand canned tuna states it will "not source yellowfin, southern bluefin or bigeye tuna, all of which are overfished, or are in danger of being overfished," however in late August the retailer was caught breaching the policy. Mr Leck said responsibility lies not only with the commercial fishing industry, but with governments across the globe. Men working on a reclamation scheme to build another exclusive hotel resort on what was formally sea bed in Dubai, UAE. Credit:Global Warming Image/WWF "Globally I think oceans haven't received the same level of conservation focus as other ecosystems," he said, citing the Solomons, Papua New Guinea, the Philippines and Indonesia, where large populations depend on the oceans for their livelihoods. "We've always thought of protected areas as an environmental measure and not a livelihood measure. But protecting these resources goes far beyond being environmental issue, it's human welfare issue."

Father and son fishermen in dugout canoe bringing in a net at sunset, Ohoidertutu Village, Kei Islands, Moluccas, Indonesia. Credit:Juergen Freund/WWF Mr Leck said there was definitely optimism in the sector upon hearing the news of Malcolm Turnbull being sworn in as Prime Minister, as "one of his previous roles was as environment minister". "He has a very keen understanding of the serious environmental issues we face in Australia...I think we should definitely be hopeful and optimistic his government will again lead on environmental issues." Cyanide fishing in a coral reef, Philippines. Credit:Juergen Freund / WWF ADDITION:

Since August Coles has updated its sustainability policy after working with our suppliers to source a certified sustainable yellowfin tuna for our customers. Small outrigger boat with fisherman pulling up a newly caught yellowfin tuna by hook and line, Gorontalo, North Sulawesi, Indonesia. Credit:Juergen Freund / WWF "The environment in which fisheries operate is complex and ever-changing. The sustainability of fisheries can change as new management measures are introduced and better fishing techniques are adopted," a Coles spokesperson said.