Interactions between farmed and wild fish An overview 2 Unique challenges in fish New species are domesticated at a much more rapid speed – both in numbers and efficiency than ever before in history Difficult (or impossible) to avoid escapees When escaped – large areas can be influenced Often introduction to new areas Number of individuals farmed can be much larger than in wild population 3 4 Two important misconceptions regarding selection
Farmed strain Distribution of the fitness trait Nature Farm Environment 12 Major problems with Norwegian farmed salmon In some small rivers, more than 50% of the migrating fish are of farmed origin They often come in late in the season 0 ruin the nests of the wild parent’s Offspring tends to be more active and faster growing 0 compete for scarce resources 13 14 Other treats for the wild salmon populations The greatest threats for the wild salmon populations are the regulation of the rivers, mostly due to power plants – E. . in the county Hordaland
