Salmo domesticus was created in Norway in the hopes to achieve the selective breeding that the U.S. had begun to discover. Salmon eggs are considerably larger than most other fish eggs and when the fish are growing inside the egg they simply feed on the egg for the first few weeks of life. Other species of fish are not able to do this and require a safe space to live and small enough food to find. It was found that if the young salmon were able to be protected and given sufficient food their survivability would increase. Which would lead to Gjedrem and Skjervold narrowing down the specific salmon they wanted to breed and create a new generation of farmed salmon from their wild parents.
I think that it’s great they are able to provide salmon to places that had never had salmon and struggle with having enough food for everyone but as Greenberg mentions in the book, roughly a million farmed salmon make it into the wild every year. Those farmed salmon can cause huge problems for the wild salmon population in that area. I would think there is more damage that could come from the farmed salmon population than positive changes in the wild ecosystems. Somethings that come to mind are: If there were no farmed salmon population would there be an increase in commercial salmon fisheries to fill that void? How much of a hit would the wild salmon population take to make up for the loss of the farmed salmon?