T1B41

When we were at the salmon run my dad and I both wondered why there were so many obstacles for the fish to cross. There was a mini waterfall at every other bend, and at the other ones there were bigger waterfalls. My dad said it might have been because they only wanted the stronger salmon to make it all the way, so the next generation of salmon were also strong. I think he was right, although I don't know if salmon genes get passed on in their offspring. 

Okay, I've just searched it up. Yes, they DO get passed on. Apparently in Norwegian rivers, the farmed salmon have been escaping and spawning with the wild salmon that could cause weakened salmon populations. There can be all sorts of problems caused by farmed salmon interbreeding with wild salmon such as less genetic variety, etc.

I don't really understand it all.

Also, this article was published I don't know when, so it could be pretty old.

It's still totally relevant and interesting though, because I think that by producing such a complicated course for salmon to swim through, they may be encouraging not just strength, but also they kill a LOT of salmon throughout this process, because if they are tired and can't swim anymore, they just dwindle there and the people at the farm just throw them away when they're dead. Which is really sad, and seems like it could have a negative effect somehow on salmon population/traits.