For years, scientists thought stray plastic bags or cups dumped on our beaches or tossed overboard were the primary cause of the massive “great Pacific garbage patch,” which was discovered in 1997 by a yachtsman off the coast of California. But according to a new study published in Scientific Reports, around half of the 79,000 tons of plastic floating in the 1.6 million square-kilometer patch — an area twice the size of Texas — is made up of degrading synthetic-fiber fishing nets. And a majority of the rest of the trash is cast-off plastic fishing gear: fragments of ropes, traps, baskets, and crates. More sad news: the patch is much larger than scientists expected and only seems to be growing.
Laurent Lebreton, an oceanographer with the Ocean Cleanup Foundation and lead researcher of the study, and his team argue that around 60 percent of plastic is less dense than seawater, so it is carried by surface currents and wind to these central patches, where it slowly degrades into micro-plastics (smaller than 10 millimeters).
To give scale to this problem: Some 320 million tons of plastic are produced each year. Only a small percentage is recycled or incinerated; the vast majority is dumped into landfills or becomes litter — and about 8 tons of that enters our oceans every year. While the great Pacific patch is a “major oceanic pollution hot spot,” plastic trash is found throughout our oceans and seas.
If micro-plastics don’t kill the fish, they eventually work their way up the food chain. (Micro-beads found in cosmetics were a particularly toxic form of micro-plastics banned by President Barack Obama in 2015). But even taking a bite of a larger piece of plastic — say, a bottle cap or the remnants of a net, which could be easily mistaken for a jellyfish — can kill a sea turtle or larger fish.
And in their afterlife, remnant plastic fishing nets found in the patch, cast-offs from the shipping, fishing, or aquacultural industries, are still trapping ocean life. National Geographic writes: “Ghost nets, a term coined to describe purposely discarded or accidentally lost netting, drift through the ocean, entangling whales, seals, and turtles. An estimated 100,000 marine animals are strangled, suffocated, or injured by plastics every year.”
Lebreton’s organization — the Ocean Cleanup Foundation — is determined to get rid of this floating menace. The foundation’s founder, Boyan Slat, was just a teenager when he proposed his brilliant idea: a 1.2-mile-wide, U-shaped collector that would passively use wave currents to move an underwater screen and gather and concentrate garbage for boat pick-up.
Now 23, Slat has received millions in grants from the Gates Foundation and other sources. His organization is prototyping the device, which they believe will remove 50 percent of the trash in the Pacific patch in just five years, and then clean up the other gyres by 2040.
They are launching off the coast of California not a moment too soon: Another new study — Foresight Future of the Seas from the British Government — found the garbage-laden gyres could triple by 2050 without more determined action.
What we can do on land: In addition to coastal clean up efforts, like the inspiring one underway on India’s beaches, every beach and coastal destination should have ample and well-maintained garbage and recycling bins.
Communities can ban plastic bags, and consumers can decide to stop purchasing non-biodegradable disposable products. Environmental groups are already working with seafood industry players and local fishing communities alike to collect and recycle abandoned fishing nets, but that effort needs to be scaled up. We need more products made out of old fishing nets.
And to ensure more people care about these efforts for the long run, cities and communities should take up the biophilic approaches of Blue Urbanism, a book written by professor Timothy Beatley. For him, the over-arching goal must be a “complementary, mutually sustainable relationship between city and ocean,” forged out of a deep connection to the blue world.