Firing Fish

There has been a real problem for wild salmon attempting to journey back up the Fraser river (British Columbia, Canada) in order to spawn (https://www.theguardian.com/environment/2020/jun/15/canada-wild-salmon-fish-ladder-salmon-cannon-british-columbia-aoe). A huge landslide into the river that occurred at exactly the wrong time of the year, prevented the fish from swimming up the river to the spawning sites. Local people and experts worked very hard to help the fish (albeit in very reduced numbers) to make the migration. One of the devices now incorporated into the area is a Pneumatic tube (nicknamed the 'Salmon cannon') that 'fires' the fish up river!