New Atlas —
Back in 2014, we heard about a so-called “fish gun” or “salmon cannon” that safely shot spawning fish up over river-blocking obstacles such as dams. Its successor is now in use, offering a couple of key advantages over the original system.
Manufactured by Seattle-based Whooshh Innovations, the salmon cannon’s actual name was the Whooshh Transport System. To recap our previous coverage, it was basically a flexible plastic tube hooked up to a motorized air pump. One end of that tube was located in the river at the bottom of the dam, while the other was located up at the top.
The original “salmon cannon,” as it was dubbed on social media, was first used to get fish into a truck or when handling/transferring them into a hatchery or aquaculture operation. The fish were manually loaded into the bottom end of the system, where the lower air pressure inside sucked them in and up the tube. A pressure difference of about 2 PSI shot the fish along at 5 to 10 m/sec (16 to 32 ft/sec).