Overfishing has caused cod to halve in body size since 1990s, study finds

Evolutionary change driven by intensive fishing led cod to ‘shrink’ from average 40cm length in 1996 to 20cm in 2019

Overfishing has led to a collapse in the eastern Baltic cod population, but over the past three decades the size of the fish themselves has also been dramatically and mysteriously shrinking.

Now scientists have uncovered genomic evidence that intensive fishing has driven rapid evolutionary changes that have contributed to these fish roughly halving in average body length since the 1990s.