Overfishing

The Grand Banks cod collapse, in which a population supporting 500 years of fishing virtually disappeared within two decades of industrial fishing, is the paradigmatic example of overfishing consequences. The collapse cost 35,000 jobs and has not recovered despite a moratorium maintained since 1992, demonstrating that fishing pressure can drive populations below the minimum viable threshold for self-recovery. Two-thirds of global fish stocks are now at or beyond sustainable limits. Overfishing removes large, reproductively valuable individuals disproportionately, causing evolutionary pressures toward earlier maturity and smaller body size — 'fisheries-induced evolution' that reduces long-term stock productivity.