How That Mesmerizing Fish Tube Works

The viral salmon cannon video, explained.


If you’re like us, you were probably enthralled by a hypnotic video that emerged from the depths of the Internet to take charge of Twitter and capture the hearts of millions over the weekend. Just why did these fish flying through tubes resonate so soundly? Better to not look a gift fish in the mouth.

Though the strange salmon cannon has suddenly caught fire, it turns out the quick process of spitting fish through tubes to hurdle over obstacles in water has been a focus of wildlife experts for years. The method isn’t new, especially in Washington State, where government and tribal agencies have utilized this exact Whooshh Innovations system for more than five years.

Originally developed to gently handle fruit in the country’s Pacific Northwest orchards, the uses of the Whooshh system quickly morphed to not only keep fresh fruit from bruising, but to move live fish over dams and around obstructions at an incredibly quick rate.

Part of the appeal of the salmon cannon is its apparent element of danger, like a roller coaster for fish. But Mark Johnston, a research scientist for Yakama Nation Fisheries in central Washington, says the tube is perfectly harmless. “The fish fly right through without so much as a scratch,” Johnston says in a press release.

The Whooshh tubes can accommodate a variety of fish sizes, from as small as a herring to as large as a sturgeon, but generally focus on fish between 2 and 34 pounds. Once fish enter the tube—either by manual placement through a false weir called a “fish faucet,” or via a gravity slide—the soft tubing then forms to the size of the fish.

By conforming the tube to the fish, there’s no need to move a column of water, ensuring no practical height limit to the tubes’ ability to rise over dams. This allows the system to easily handle any length, which makes a 1,700-foot-long project a relative walk in the park.

The fish are essentially pushed through the system using an average of one to two PSI, which independent studies verify results in no scale loss, eye damage, or other injuries.

Using this model, the system builds lower air pressure in front of the fish and more behind them with just a single blower motor, working just like a pneumatic tube at a bank, Whooshh CEO Vince Bryan III tells Popular Mechanics. “They just glide because there is essentially no friction in the tube,” he says.

Whooshh Innovations

In a typical system, the fish travel between 16 and 26 feet per second (about 18 miles per hour), which accounts for about 40 fish per minute. If fish exit into open waters, the system may not employ a deceleration system, but if they drop into a confined area, sensors in the system can slow speeds near the end of the tube.

“Good engineering and mathematics went into the angles,” Bryan says, “so a fish that follows isn’t hitting the one that came out before.”

The water in the tube comes as lubrication only, although auxiliary misters can be added if required, using an additional nine gallons of water per hour.

“It’s definitely much more efficient,” Elise Olk, a scientific technician for the Washington Department of Fish and Wildlife, says in a press release. “It’s less handling for the fish, too.”

The tubes themselves can float on water, attach to existing cables, or seemingly suspend in the air hanging from cables, allowing for deployment in a variety of wildlife regions without the need for added infrastructure.

Whooshh has created multi-tube versions for fish of different sizes that need to use the same passage. Larger fish move past small openings until they find the ones that fit, while smaller fish approaching large-tube intakes are redirected into smaller ones by water cascades.

The Whooshh system has grown popular because not only does the speed of moving the fish save time and money for the agencies looking to safely transport fish, but it also comes as a gentler solution for the animals themselves. Plus, the videos are cool.

“The process is much easier on the fish than the old method that involved totes and forklifts and a lot more time,” Eric Kinne, the hatchery reform coordinator for the Washington Department of Fish and Wildlife, tells Popular Mechanics.

Not only can fish transport cause high stress for the fish, but the installation of fish ladders uses more resources to operate and can be strenuous on the fish trying to navigate.

“The sky’s the limit on these things,” Kinne says. “It seems to be very easy on the fish.”

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