krijack-

In some ways raising the fish in pens increase ESA concerns. What was seen at the time of the ESA listing of Puget Sound Chinook the uncaught Chinook returning to those net pens shot gunned through out the region straying to a number of rivers without anyway to collect most of the fish at a hatchery rack.

A far cheap alternate or additional method of adding to the biomass of hatchery Chinook available to the orcas would use selective breeding techniques to reverse the size selection that has occurred to the hatchery Chinook returning to Puget Sound hatcheries. Since the mid-1950s those fish have gotten significant smaller. It would be straight forward to increase the average size of Puget Sound adult Chinook say by 20% without much additional cost. This would result in a 20% increase in the biomass of hatchery Chinook available to the orca and at the same time not increasing the number of unwanted hatchery on the spawning grounds.

Curt