Oceans running out of oxygen say scientists
That’s the conclusion of the biggest study of its kind, undertaken by conservation group IUCN.
While nutrient run-off has been known for decades, researchers say that climate change is making the lack of oxygen worse.
Around 700 ocean sites are now suffering from low oxygen, compared with 45 in the 1960s.
Researchers say the depletion is threatening species including tuna, marlin and sharks.