FISHERS shouldn’t throw small fry back to help preserve fish stocks. Contrary to popular belief, and fishing policy, it’s the big ‘uns that should be returned to the sea.
According to David Conover of Stony Brook University in New York, catching larger fish creates a selection pressure that forces down the size of individual fish. He raised populations of Atlantic silverside (Menidia menidia) in laboratory tanks and removed either the largest 90 per cent of fish in each generation, or the smallest.
Within just four generations of taking larger fish, individual adults averaged 1.05 grams, compared to 6.47 grams if…
