George Sugihara of the Scripps Institution of Oceanography at the University of California San Diego said in a statement, told that people adopt this popular belief as it has become a regulation, which we see in many sport fisheries, but it is exactly wrong. He added that it is not the young ones that should be thrown back, but the larger, older fish that should be spared.
According to Sugihara the older fish not only provide stability to the population, they also provide more and better quality offspring. In one of his writing Sugihara said that the current policies that manage according to biomass targets instead of individual fish size can also destabilize the population.
He explained that a single large fish will simply grow a little when it gets more food, or lose a little weight when food is scarce. He added that the increase and decrease of a population of many young, small fish, however, depends on food availability. He told that it is especially important to know when trying to rebuild fish stocks. He suggests that a high harvest target may be set after an especially abundant period when the population may be poised to decline on its own.
