Since the dawn of modern fisheries releasing the smaller and younger fish from nets has been management’s dogma. We’ve been always told to fish only or mainly older, larger fish, and let the younger and smaller fish grow, mature and procreate. The assumption has been that the surviving spawners will produce
huge numbers of eggs and larvae, more than enough to replenish the population. Scientists and managers were prescribing minimum
hook sizes, and minimum mesh sizes for gillnets, trawl codends,
and seine bags.
But, recently more and more scientists appear todissent from
this dogma. What in fact we do, they say, is that by removing the large spawners, who produce large eggs and strong larvae, we
let spawn only the smaller ones, who produce much less and
smaller eggs per spawner and, consequently, smaller, weaker
larvae. Such selection may also lead to fish spawning at lower
age and much lesser size. Remember cod? It would spawn not before the age of 6, when it was three quarters of a meter long.
And now?... St.Bernard has become a poodle...
Inagine a human population of which every individual, who
exceeds 1.60 m in height is removed, so that only the short ones can procreate. How would such population look after several
generations?
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