However, in some areas of the coastal ocean, when they die they deplete the ocean of oxygen, causing massive fish kills, and the feedbacks are hard to imagine. (dotearth.blogs.nytimes.com)
Indeed, hydrogen sulfide, ammonia and other compounds from river sediments probably caused massive fish deaths in July, scientists have concluded, and crocs eating these contaminated fish could have been affected. (scientificamerican.com)
The problem with fish stocks is the problem with so much of everything else, remember in the 1970's and 80 ′ when the Soviet's would park outside our waters with massive fishing fleets including a canning mother ship would process right on the water cleaning everything out? (dotearth.blogs.nytimes.com)