Salmon cannons are real. And they're doing a wonderful thing. With dams and other impediments to getting upstream, Whooshh Innovations had a solution. The Salmon Cannon can get them there.
The cannons were made for moving fruit. But hydroelectric dams in the Pacific southwest have made it difficult for salmon to do what's they gots to do: swim upstream!
But they get to do it in a reverse gravity water slide.
Unlike the video below (from 2016), the salmon using the salmon cannon today voluntarily swim into the open mouth of the cannon and come out the other side unharmed, and more importantly, upstream.
Sure, it sounds like something a bunch of guys came up with while drinking moonshine, but this actually helps someone instead of hurting them. "Hey y'all, watch this!"