After posting this I began to wonder if I had not jumped to conclusions about this, not having read the paper. I emailed the autor and he very gratiously sent me a copy of the paper. The jury is still out on exactly the mechanism of the genetic change:
From the paper:
Many fitness correlates decreased as a result of harvesting the largest individuals in the population. These correlated responses could be indirect responses to a harvest-induced decline in maternal size or adaptive responses to the new fitness landscape. Regardless of the mechanism, they decrease the intrinsic capacity for the population to rebound under natural conditions. A new Darwinian fisheries paradigm is needed in order to account for such impediments to recovery and to ensure sustainable yields over evolutionary time scales.
Anyone who would like to read the paper send me a PM with your email and I will send it to you. Sunil I am sending you a copy.
