Fish Tube: How the 'Salmon Cannon' Works and Why It's Important

PerfectStills/iStock via Getty Images
PerfectStills/iStock via Getty Images

If you’ve been on the internet at any point in the past week, you’ve certainly come across footage of wildlife conservationists stuffing salmon into a giant plastic tube and shuttling them over obstacles. It’s so bizarre—even by the already loose standards of the web—that it briefly ignited discussions over fish welfare, its purpose, and the seeming desire of people to be similarly transported through a pneumatic tunnel into a new life.

Naturally, the “salmon cannon” has a mission beyond amusing the internet. The system was created by Whooshh Innovations, a company that essentially adopted the same kind of transportation system featuring pressurized tubing that's used in banking. Initially, the system was intended to transport fruit over long distances without bruising. At some point, engineers figured they could do the same for fish.

The fish payload is secured at the entrance of the tube—acceptable species can weigh up to 34 pounds—and moves through a smooth, soft plastic tube that conforms to their body shape. Air pressure behind them keeps them moving. The fish are jettisoned between 16 and 26 feet per second to a new location, where they emerge relatively unscathed. Because there’s no need for a water column, the tubing can cover most terrain at virtually any height.

The tubing solution is a human answer to a human problem: dams. With fish largely confined to still bodies of water thanks to dams and facing obstacles swimming upstream to migrate and spawn, fish need some kind of assistance. In the past, “fish ladders” have helped fish move upstream by providing ascending steps they can flop on, but not all fish can navigate such terrain. Another system, trapping and hauling fish like cargo, results in disoriented fish who can even forget how to swim. The Whooshh system, which has been in used in Washington state for at least five years, allows for expedient fish export with an injury rate as little as 3 percent, although study results have varied.

The video features manual insertion of the fish. In the wild, Whooshh counts on fish making semi-voluntary entries into the tubing. Once they swim into an enclosure, they’re curious enough about the tube to go inside.

If all goes well, the system could help salmon be reintroduced to the Upper Columbia River in Washington, where the population has been depleted by dams. Testing of the device there is awaiting approval from the U.S. Army Corps of Engineers.

[h/t Popular Mechanics]

This Course Will Teach You How to Play Guitar Like a Pro for $29

BartekSzewczyk/iStock via Getty Images
BartekSzewczyk/iStock via Getty Images

Be honest: You’ve watched a YouTube video or two in an attempt to learn how to play a song on the guitar. Whether it was through tabs or simply copying whatever you saw on the screen, the fun always ends when friends start throwing out requests for songs you have no idea how to play. So how about you actually learn how to play guitar for real this time?

It’s now possible to learn guitar from home with the Ultimate Beginner to Expert Guitar Lessons Bundle, which is currently on sale for $29. Grab that Gibson, Fender, or whatever you have handy, and learn to strum rhythms from scratch.

The strumming course will teach you how to count beats and rests to turn your hands and fingers into the perfect accompaniment for your own voice or other musicians. Then, you can take things a step further and learn advanced jamming and soloing to riff anytime, anywhere. This course will teach you to improvise across various chords and progressions so you can jump into any jam with something original. You’ll also have the chance to dive deep into the major guitar genres of bluegrass, blues, and jazz. Lessons in jam etiquette, genre history, and how to read music will separate you from a novice player.

This bundle also includes courses in ear training so you can properly identify any relative note, interval, or pitch. That way, you can play along with any song when it comes on, or even understand how to modify it into the key you’d prefer. And when the time comes to perform, be prepared with skilled hammer-ons, pull-offs, slides, bends, trills, vibrato, and fret-tapping. Not only will you learn the basic foundations of guitar, you’ll ultimately be able to develop your own style with the help of these lessons.

The Ultimate Beginner to Expert Guitar Lessons Bundle is discounted for a limited time. Act on this $29 offer now to work on those fingertip calluses and play like a pro.

 

The Ultimate Beginner to Expert Guitar Lessons Bundle - $29

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A Prehistoric Great White Shark Nursery Has Been Discovered in Chile

Great white sharks used prehistoric nurseries to protect their young.
Great white sharks used prehistoric nurseries to protect their young.
solarseven/iStock via Getty Images

Great white sharks (Carcharodon carcharias) may be one of the most formidable and frightening apex predators on the planet today, but life for them isn’t as easy as horror movies would suggest. Due to a slow growth rate and the fact that they produce few offspring, the species is listed as vulnerable to extinction.

There is a way these sharks ensure survival, and that is by creating nurseries—a designated place where great white shark babies (called pups) are protected from other predators. Now, researchers at the University of Vienna and colleagues have discovered these nurseries occurred in prehistoric times.

In a study published in the journal Scientific Reports, Jamie A. Villafaña from the university’s Institute of Palaeontology describes a fossilized nursery found in Coquimbo, Chile. Researchers were examining a collection of fossilized great white shark teeth between 5 and 2 million years old along the Pacific coast of Chile and Peru when they noticed a disproportionate number of young shark teeth in Coquimbo. There was also a total lack of sexually mature animals' teeth, which suggests the site was used primarily by pups and juveniles as a nursery.

Though modern great whites are known to guard their young in designated areas, the researchers say this is the first example of a paleo-nursery. Because the climate was much warmer when the paleo-nursery was in use, the researchers think these protective environments can deepen our understanding of how great white sharks can survive global warming trends.