The Catch with Netting

The ocean is a beautiful place filled with crystal blue waters, colorful coral, and magnificent creatures; however, as the developing human world collides with the ocean, the natural beauty and wonder within has begun to vanish. The sparkling waters are becoming soiled with trash both large and microscopic, the colorful coral is bleaching, and the magnificent creatures are being killed for one reason or another. It is clear that the meshing of these two worlds isn’t as seamless as one would hope, and while its effects seem to only be a hazard to the life within the ocean, the degradation of such a delicate ecosystem begins to affect the world as a whole. Whether it’s from the bioaccumulation of microplastics as fish are consumed or unjust murder for “humanity’s benefit”, the ocean is suffering. Many solutions for these problems have been discussed and are being experimented with, but the one to be discussed here, which offers a piece of the solution to both of these issues, is the development of a new technology called “Electric Shark Punching.” Before discussing this innovative technology, let’s get a little background on the effects of plastic netting and how that plays into the intentional/unintentional killing of ocean life.

Though not commonly considered a huge contributor to plastic pollution, abandoned netting, initially used for fishing or beach goer protection, can lead to both the entanglement and death of assorted wildlife and/or the formation of microplastics. Wandering nets kill without reason taking any life that gets entangled in it, whether it’s a dolphin, turtle, or shark. One report, issued jointly by the Food and Agriculture Organization and the UN Environment Program (UNEP), estimated that 640,000 tons of ghost nets are spread across our oceans, making up 10% of ocean litter. While fishermen may try to ignore many environmental statistics, they are sure to listen and help with the cause when they hear figures such as: one abandoned net can kill $20,000 worth of Dungeness crabs in a year while removing a net costs only $1,358. In addition to strangulation, mismanaged plastic netting will break apart into small pieces called microplastic. While you may not be able to see them, a recent study published in the Environmental Research Letters predicts approximately 93-236 thousand tons of microplastics are floating around in our oceans that are affecting smaller organisms and leading to negative effects on larger fish. These are the same large fish that are ending up on our dinner plate and in our stomachs, microplastics and all. With evidence of microplastics halving oyster reproduction and damaging implications of DDT and BPA being able to adhere to microplastics, there is no telling what kind of harm the build-up of these in our oceans and consequently a human body could cause.

Fisherman need to fish and asking them to change their fishing habits is a huge hurdle, but all hope for decreasing plastic netting is not lost. Another use for netting in the oceans is for beach protection from dangerous animals like sharks, and that’s where “Electric Shark Punching” comes into the scene. This innovative technological experiment is being performed by the KwaZulu-Natal Sharks Board in a shark hot spot off the coast of Southern Africa. Instead of putting up a physical barricade, the KwaZulu-Natal Sharks Board decided to go after a physiological barrier specific to sharks. Sharks have a pouch of gel that sits right on the tip of its nose used in its hunt for pray. This same pouch is extremely sensitive to any electric field, so what researchers are aiming to do is lay a cable along the ocean floor that will form an electric field causing sharks to turn back. The project leader Paul Von Blerk compares the effects of the electric field on a shark to a human’s response to heat, “From a distance, we can sense the warmth [fire] emits, but the closer we get the more discomfort we experience. Once the discomfort gets too much we can move away from the flame.” The electric field effects no other fish allowing them to pass freely across the barrier, as well as humans though they may feel a slight tingling.

Do you think this is a technology worth investing in? Are there possible repercussions you can imagine that may not have been thought of here? Are there any other circumstances you feel this technology would apply or other technologies you know of that are similar to it?

Sources:

1. Dr. Jambeck and her research team
2. http://www.earthisland.org/journal/index.php/elist/eListRead/ghost_fishing_nets_invisible_killers_in_the_oceans/
3. http://www.seadocsociety.org/california-lost-fishing-gear-removal-project/
4. Environmental Research Letters (iopscience.iop.org…/124006;jsessionid=123F0E078E457FC6106D3ACEE956F209.c3.iopscience.cld.iop.org)
5. https://voices.nationalgeographic.org/2016/04/04/pesky-plastic-the-true-harm-of-microplastics-in-the-oceans/
6. https://www.smithsonianmag.com/innovation/electric-fence-wards-sharks-180953380/