A groundbreaking Scripps voyage led by students helps define a rising environmental threat
By Mario C. Aguilera
Last summer, minutes before leaving port on a voyage to the North Pacific Ocean Gyre, Chief ScientistMiriam Goldstein was frank about what might and might not be encountered during the expedition toa place that’s become known as the “Great Pacific Garbage Patch.” Goldstein made it clear to fellowscientists, cruise volunteers, and a few members of the news media that SEAPLEX would be an exploratory voyage.
The expedition was designed to locate and study plastic and other marine debris in the gyre. But findingthe stuff wasn’t guaranteed. In some ways, the voyage would pay tribute to the grand oceanographic explorationdays of yesteryear when seagoing scientists plunged into the great unknown of the ocean frontier.SEAPLEX (Scripps Environmental Accumulation of Plastic Expedition) was designed to learn somethingabout the scope of the debris problem. It’s quite possible, Goldstein said, thatthe graduate student researchers leading the trip — despite diligent preparations and knowledge gained from previous trips headed by the Algalita Marine Research Foundation — might notfind any plastic in the gyre.
But less than a week into the voyage such provisos evaporated into wisps of sea air. The plastic indeedwas there in the gyre. And there was lots and lots of it.
During the second week of the expedition, Goldstein and three SEAPLEX voyagers sat in an inflatable boatdeployed off the Scripps research vessel New Horizon to examine the debris up close. Hollywood couldn’thave framed a more striking scene with a blazing summer sun and an extraordinarily calm sea that bordered on disturbing.
But way out here in the open ocean, a thousand miles from land, the plastic was all aroundthe boat. Litters of small flecks were here. A floating bucket and a piece of shoe there.
Today, the graduate student researchers are well into the analysis phase of their science. Now thatthe plastic has been found and documented, they are hoping the SEAPLEX journey will reveal answers toquestions such as how the plastic is impacting the gyre’s marine ecosystems and animals. The informationwould provide key information about human-produced marine pollution and how to grapple with a risingenvironmental problem that could be turning all of the ocean’s gyres into trash dumps.
Plastic in a Biological Desert
From a visual perspective, the SEAPLEX voyagers encountered jaw-dropping displays on a daily basis. Vivid, glassy blue waters gave way to purple-crimson sunsets, which gave way to pitch-black nights and a dome of stars that surrounded the ship, seemingly at arm’s reach.
Sea life observed from New Horizon was spectacular, from curiously shaped sunfish to albatrosses and an eerie vampire squid.
Still, SEAPLEX scientists called the North Pacific Gyre a “biological desert,” an area with marine life, to be sure, but devoid of robust, productive ecosystems seen elsewhere. Goldstein said there are very few large fish in the area simply because there is nothing for them to eat.
The gyre exists as a consequence of the earth’s rotation called the Coriolis Force that pushes wind in a clockwise circle around the North Pacific Ocean. The force, also responsible for gyres in the South Pacific as well as the planet’s other oceans, causes water to collect in the middle of the wind, creating a vortex known as a “convergence zone.” Gentle winds and circulation make the gyre a place most seafarers avoid and its remoteness has made it an understudied location.
“As the winds move new water into the middle of the convergence zone, the water that was there before sinks,” Scripps graduate student and SEAPLEX voyager Pete Davison exploained. “The sinking water leaves floating material behind. New plastic comes in and the old plastic stays behind.”
Scripps graduate student researcher and SEAPLEX zooplankton specialist Jesse Powell’s grim assessment was obvious not only in his words but plain to see on his face.
While bringing up a sea surface sampling device called a manta net off the side of New Horizon, Powell and a volunteer accidently slammed the instrument against the side of the ship, causing the manta’s frame to snap at its apex. This was not a trivial setback.
Scientists deploy manta nets, named because of a shape that resembles a manta ray, to collect small specimens and objects from the sea surface. Now, early into the SEAPLEX voyage, Powell held the wounded device in his hands. It was virtually useless in its broken state.
Randy Flannigan, the ship’s chief engineer, and his team quickly devised a solution. Their impromptu repair was a success.
By the early morning hours of the next day, the manta net would be the first of the expedition’s four main collection tools to retrieve plastic samples. More would be found with the manta net later that day. In the end, it collected plastic samples in every haul, for more than 100 consecutive tows across a distance of more than 2,375 kilometers (1,700 miles).
“The thing that has shocked me and I think the rest of the science crew is just how much plastic is out there,” said Goldstein. “We found a lot of plastic because there is a lot of plastic out there.”
During the survey in the inflatable boat, Goldstein used a quadrat, a frame that defines an area of a habitat, to gauge the quantity of plastic in a given area. At maximum, she detected 11 pieces per square meter.
“That’s a lot of anything to be out in the open ocean,” said Goldstein. “The thing I found sad and shocking was that we could see some amazing, cool creatures just below this thick layer of plastic. Here’s this very unstudied ecosystem where not many people come and there is all this stuff floating at the top that’s a sign of industrial society.”
The Garbage Patch Kids
As New Horizon began steaming back to port, the researchers discussed the lessons learned from the voyage, especially facts countering public myths about the Garbage Patch.
Yes, they found lots and lots of plastic and debris in the gyre, but no, the “patch” isn’t an island of trash, as is commonly believed. You can’t walk across it. There is indeed a vast amount of large pieces of debris, but by far the overwhelming majority is broken down bits of plastic the size of a thumbnail and smaller. You can’t see a defined patch or a swirl of debris from the air or space. The plastic is dispersed across thousands of miles of ocean.
As for the size of the Garbage Patch, “twice the size of Texas” has been conjectured in countless news reports. Goldstein believes, however, that much more exploration and analyses are needed to obtain a true definition of its size, if true boundaries can be demarcated.
Hundreds of samples and specimens from SEAPLEX are being analyzed and results are on the horizon. For Davison, the “fish guy” on the science team, the specimens have already yielded tantalizing returns. He and fellow Scripps graduate student Rebecca Asch have dissected the stomachs of more than a hundred specimens. In their Scripps laboratory, they have used a stain and filtering process to segregate biological from human-made substances and found direct evidence that deep-sea gyre fish such as lanternfish are ingesting bits of plastic. Even a low percentage of plastic ingestion is raising troubling questions about how garbage can work its way through the marine food chain.
“The pollutants are potentially harmful to the fish,” Davison said. “We don’t eat these fish directly, but fish that we do eat feed on them so plastic entering the food chain may be a concern to people.”
Chelsea Rochman, a San Diego State University and UC Davis graduate student, is analyzing the toxicological aspects of plastic ingestion by animals in the gyre, specifically how plastics might be a transport medium for toxins such as the industrial chemical BPA (bisphenol A) to enter the food web, with possible future implications for human health.
Goldstein is probing the impact of plastic debris on marine invertebrates. Students Darcy Taniguchi and Meg Rippy are analyzing water samples taken during the cruise to investigate the influence of debris on bacteria and phytoplankton.Through SEAPLEX, the scientists have set a baseline that will inform future missions targeting the North Pacific Gyre, and possibly other ocean gyres in the future.
Doug Woodring is a business executive, environmentalist, andcofounder of Project Kaisei, which supported part of the SEAPLEXexpedition along with UC Ship Funds. He used the expedition as a springboard to begin to formulate solutions to the plastics problem on different fronts. At sea, he and his partners are evaluating new remediation technologies and techniques to capture debris. On land, he is discussing solutions with multinational industry representatives to encourage new packaging — specifically biodegradable materials — in an effort to stop the garbage problem before it ever reaches the sea.
“Like most people, I expected to see large volumes of big material en masse in the gyre. I now realize that the sun plays a big role in breaking down material, which then degrades and scatters,” said Woodring.
Although human-produced plastic made its debut in 1862 at the GreatInternational Exhibition in London, the material propagated throughmass production in the 1930s and ’40s. By the 1970s, plastic found itsway into virtually every aspect of human lives.
Despite gains in recent years, Woodring says that approximately 90 percent of all consumer materials are not recycled. When SEAPLEX’s scientific findings emerge, he hopes they will force societies into thinking about the plastic surrounding them.
“It’s tragic that (the ocean debris problem) has been allowed tohappen, and it happened in the last 40 or 50 years,”said Woodring. “A lot of plastic is permanentmaterial for disposable uses. This should be a wake up call to all ofus that we need something more environmentally friendly.”
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