fish farms had just gone commercial in the 70's but hadn't grown that much at the time. the excess of high quality fish was wild salmon.

in the 70's in norway (and in alaska, can't speak about anywhere else) commercial fishing was in it's prime.

you can read more about the history of norwegian aquaculture here. http://www.svt.ntnu.no/iso/anders.skonhoft/Marine%20Policy%2...