Revolution Filmmaker, Rob Stewart narrates this video on the effects of Overfishing. 80% of life on earth lives in the ocean and the oceans provide 70% of our oxygen. Sharks have been a dominant predator, but their populations have dropped 90% through global overfishing to supply the shark fin soup trade. Between 70 to 100 million sharks are fished each year. Fish are a main protein source for 1/3 of the planet. Four million pounds of by-catch are discarded each year. The UN has stated that the world’s fisheries will collapse by 2048. Global overfishing and ocean acidification are key issues facing the oceans.