Reuters, Oslo :The amount of fish in the oceans has halved since 1970, in a plunge to the “brink of collapse” caused by over-fishing and other threats, the WWF conservation group said on Wednesday.Populations of some commercial fish stocks, such as a group including tuna, mackerel and bonito, had fallen by almost 75 percent, according to a study by the WWF and the Zoological Society of London (ZSL).Marco Lambertini, director general of WWF International, told Reuters mismanagement was pushing “the ocean to the brink of collapse”.”There is a massive, massive decrease in species which are critical”, both for the ocean ecosystem and food security for billions of people, he said. “The ocean is resilient but there is a limit.”The report said populations of fish, marine mammals, birds and reptiles had fallen 49 percent between 1970 and 2012. For fish alone, the decline was 50 percent.
