We have salmon farms here in Maine. I prefer them to the west coast wild ones, but as is often the case, they are confined to a small area and pollution of their own making is causing a serious problem.
It all boils down to one thing; fishermen are just too efficient. That applies to all fish. However, the drop in cod stocks is responsible to a great degree for the abundance of lobsters. They took far more lobsters than seals that used to get the blame for any drop in the lobster population.

We are slowly wearing out our planet just as Ethiopians wore out their country.

It's a dirty bird that beshits its own nest.And that's us, folks.