Overfishing is catching too much fish. It is a type of overexploitation where fish stocks are reduced to low levels. It is a good example of what is good for the short term is not good for the long term. Also, what is good for some fishermen is not good for all of them (tragedy of the commons). The United Nations Food and Agriculture Organization estimated in a 2018 report that 33.1% of world fish stocks are subject to overfishing.