http://daily.jstor.org/half-fish-sea/
For example, research in Cape Cod has shown that overfishing (recreational, not commercial) of certain species such as striped bass has led to the collapse of coastal salt marshes. The predatory fish (e.g. striped bass) and crabs popular with anglers were the only thing keeping herbivore species in check, and their decline accelerated the pace at which the marsh vegetation was consumed. This is all the more significant because the marsh itself is an important nursery habitat for many species, including the predatory ones.
Snow ball, domino, butterfly; whatever you want to call it, humans will be the ultimate demise of humans.
Can we react now and make a change? Are we ultimately doomed? Is this another Al Gore hoax, meant to artificially inflate the fish market? Is this Obama's fault? Hillary's emails from Benghazi has killed all the fish?