The report, from the International Programme on the State of the Ocean (IPSO), concludes that mass extinctions will be “inevitable” if the current trend continues.
As well as overfishing, agriculture, pollution and increasing acidification as a result of carbon dioxide emissions are all playing a part in the unfolding catastrophe.
The IPSO report was compiled following an inaugural workshop at Oxford University to consider all the threats facing the world’s oceans.
Alex Rogers, scientific director of ISP, said the findings were “shocking”.
“As we considered the cumulative effect of what humankind does to the ocean, the implications became far worse than we had individually realised. This is a very serious situation demanding unequivocal action at every level. We are looking at consequences for humankind that will impact in our lifetime, and worse, our children’s and generations beyond that.”
The conditions facing marine life across the globe are the same as those “associated with every previous major extinction of species in Earth’s history”, according to the report.
Overfishing has decimated fish numbers, with numbers of some species down by 90 per cent.
But toxic and chemical pollution, whether spilled accidentally or dumped in the oceans, as well as waste and plastic detritus, has also taken a significant toll.
Add to that the “dead zones” created by agricultural run-off such as chemical fertiliser, which create low or zero-oxygen conditions, and it’s clear that something needs to be done.
IPSO is now calling on governments and the United Nations to legislate for the urgent protection of the oceans.
Read the full IPSO report