We have all been waiting for this day. Finally, shark repellent has arrived to the world… except this shark repellent is not used to save humans from sharks. No this shark repellent was made to save sharks from humans. With good reason, while only about 4 people die of unprovoked shark attacks each year, humans kill an estimated 73 million sharks each year. You do the math and tell me who is the biggest threat to whom?

Many sharks are inadvertently killed in fishing equipment used for tuna, swordfish, and other commercial fish. This is called bycatch. These unwanted sharks are often thrown back into the ocean dead, dying, or injured.

Sharks hunt by using electrically conductive sensory organs on their nose, known as ampullae of Lorenzini. Ampullae of Lorenzini detect the beating heart of their prey. A new shark repellent device has been created to stop shark bycatch that uses the sharks electrical detection senses.

A half-dollar-sized metal alloy clamped onto fishing gear protects sharks by creating a mild electrical current. The alloy sends out an electrical current 6-8 times the amount the shark is expecting in a prey’s heartbeat. It is the equivalent of shining a bright light into your eyes.

This type of shark repellent unfortunately wont work for high speed predators like the great white shark, but for slow moving and solitary sharks it has been shown to reduce bycatch 64%. Fishermen might want to adopt this technology to keep sharks from breaking equipment, and taking up space on their line that was meant for fish they want to catch.

No word on if the spray form will be available for superheroes. I’ll keep you updated.

Source: Discovery News

Image Credit: Daniel Hohler

In 2003 “Nature” published a study showing that 90% of the large fish living in our oceans were fished out of existence. A group of scientists recently predicted, major seafood stocks will collapse by 2048. This is a staggering number, considering the technology and amount of people needed to cause overfishing is a relatively new phenomenon, starting really only in the late 19th century.

Most governments have shrugged these claims off, and continued their fishing practices. Alaska has shown to be the only sovereign state willing to self-police their fishing practices. Sarah Palin jokes aside… Threatened with the loss of one of its top industries, Alaska began limiting the number of fishing vessels, restricting the size of their catches; and perhaps most importantly, giving incentives to fishermen. Alaska currently gives fishermen a stake in the long-term viability of salmon and other fish.

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