Over fishing is truly a problem, but it is clearly stated that 40% of fish harvested yearly is wasted. The bigger issue is wasting food, and the way seafood is harvested.
Rain forest destruction is clearly a problem, but this is not considering the pressure a worldwide vegan/vegetarian demand would put in all ecosystems.
Wildlife is obviously affected by animal farming, but the killing of natural predators is due to ignorant farmers and hunting groups. Not that many farm animals are victims of natural predators, education in this subject is key.