Few creatures thrill and delight as thoroughly as the Sea Otter. Yet the otter you see in the Photo of the Week above offers us a highly cautionary tale as she floats on her back holding what appears to be a plastic bag between her dextrous paws and flippers.
For the Sea Otter—which we barely brought back from near extinction—still remains an endangered species. And scientists warn us that plastic, in its many forms, could compromise the existence of not only this charismatic sea creature but hundreds of other marine mammals, fish, crustaceans, and seabirds, as well.
Though invented in the 19th century, plastics came into wide use only after the 1930s. But now plastic has become ubiquitous, present in everything from our wallets to our clothes. Plastic microbeads make toothpaste, shampoo, and cosmetics easier to squeeze out and pour. Plastic bottles hold our water, milk, juice, and soda. Manufacturers use plastic to make clothing, carpets, and food storage containers; our pets’ chew toys and litter boxes; party balloons and fishing tackle. And, of course, disposable shopping bags.
And many of these plastic products—some after a single use—wind up in our landfills and our oceans.
In fact, researchers estimate that we annually dump 10 to 20 million tons of plastic into our oceans. Though some of it comes home again to litter our beaches, shorelines, and harbors, most of it washes out to sea, where it either sinks below the surface or rides the waves and tides to one of the five large “mid-ocean gyres” around the globe.
Oceanographers call one of the largest of these the Great Pacific Garbage Patch. “[D]escribed as a floating trash island the size of Russia,” according to a recent CNN article, the plastic debris found in the Great Pacific Garbage Patch extends “20 feet (6 meters) down into the water column” and by some estimates currently contains approximately “3.5 million tons of trash and could double in size in the next 5 years.” <http://www.seeturtles.org/ocean-plastic> Together, the five garbage patches around the world comprise an area equal to “40% of the world ocean—one third of the planet,” which means that as much as 17.5 million tons of plastic garbage await the fish, seals, turtles, whales, dolphins, albatross, puffins, shearwaters and other sea-going creatures that pass through these oceanic dumps every year.
What kind of garbage do these sea creatures encounter?
The larger pieces include the plastic ropes, lines, gill nets, and crab pots that legal and illegal commercial fishing fleets deploy and, often, discard. Since gill nets can consist of “thousands of miles of nets and lines,” even a portion of a single net can pose an imminent danger. These unexpected and barely visible materials float on or below the surface of the water directly in the paths of marine wildlife—including endangered species—as it feeds and migrates.
A survey, undertaken by marine biologists Sarah Gall and Richard Thompson, and referenced by Emily J. Gertz in “Ocean Plastic Pollution’s Shocking Death Toll on Endangered Animals,” reveals the dangers posed by plastic netting, lines, and ropes. Their study calls attention to “reports of 138 hawksbill turtles, 73 Kemp’s ridley turtles, and 62 leatherback sea turtles tangled in plastic. All three are listed as critically endangered—one step below extinct in the wild—on the IUCN Red List.”
The derelict fishing gear entrapped marine mammals, as well: “Marine mammals as a group proved especially vulnerable to marine plastic debris, with 30,896 of the reports involving these animals tangled in ropes or netting. They included 215 Hawaiian monk seals, a critically endangered species, and 38 endangered northern right whales, as well as 3,835 northern fur seals and 3,587 California sea lions.”
But far more species likely die as a result of the ingestion of plastic garbage than die from entrapment.
Although some forms of plastic can persist for thousands of years, it does not remain in the shapes it took as consumer or commercial products for very long. Exposure to the the sun causes sea-borne plastic to break apart into smaller and smaller pieces over time through a process called photodegradation. The smallest and most degraded members of this detritus, called “microplastics,” consist of tiny particles “smaller than 1mm (0.039 in) down to the micrometer range.” That’s about the size of many zooplankton, a large group of organisms (including creatures as diverse as krill and jellyfish) that float on or near the ocean surface and is part of the diet of many marine species, including small fish and the larger fish species that feed on them. Along with the plastic, the fish also consume the “chemical compounds in plastics that are know human carcinogens”—such as PCBs and BPA—that “are commonly found in plastic and are capable of bioaccumulating within the bodies of humans and marine species alike.”
In other words, the tuna in your sandwich may have consumed fish that previously consumed plastic laced with potentially injurious chemical compounds.
Ecologists estimate that “in the North Pacific alone, between 12,000 and 24,000 tons of plastic end up being ingested by marine species a year. Worldwide, about 100,000 animals will unintentionally consume plastic. As smaller fish consume these chemicals their concentration and toxic effect increases as you go up the food chain. When humans are at the top of that food chain, the levels of toxins we consume can be extremely harmful.”
What’s more: since fish can’t digest the microplastics they’re consuming, in addition to the swordfish, salmon, halibut, or other fish you have for dinner, you’ll enjoy a side of microbeads and other tiny plastic particles.
Unfortunately the ocean gyres contain a wide-ranging smorgasbord of plastic waste in various stages of decay in addition to the tiniest of plastic pieces. Bottle caps will float on the surface along with six-pack rings, water bottles, disposable lighters, plastic lids, straws, styrofoam cups, and single-use grocery bags.
Many other creatures besides fish also suffer. As Fur Seals, California Sea Lions, Kemp’s Ridley Turtles, Leatherback Sea Turtles, Humpbacked Whales, Sperm Whales, and other marine mammals consume the jellyfish, plankton, krill, squid, and other oceanic prey organisms, they’re also inadvertently ingesting plastic waste along with their food.
Tens of thousands of these species die from starvation, their stomachs filled with indigestible plastic.
Sea turtles looking for jellyfish accidentally consume plastic bags that, once denuded of color after chemical leaching and exposure to sunlight, appear indistinguishable from the turtle’s intended prey. “One in three leatherback sea turtles have plastic in their stomach, most often a plastic bag, based on a study of over 370 autopsies,” according to the EcoWatch article “Silent Killers: The Danger of Plastic Bags to Marine Life.” And the bags not only block the digestive tracks of turtles, but any actual food the turtles manage to consume after the ingestion of the bags gets trapped, releasing “gases that render them buoyant, and unable to dive for food.”
Whales, the largest of sea mammals, may be the most conspicuous of the marine mammals that die from plastic consumption as they often seek refuge near harbors and inlets or wash up dead on our beaches. In 2014, biologists reported a distressed Sei Whale swimming up a river “far from the deep waters of the Atlantic where the species, listed as endangered, is normally found.” Several days after being spotted, the whale died. Its “necropsy revealed the animal had swallowed a shard of rigid, black plastic that lacerated its stomach, preventing it from feeding.”
In 2013, a “dead sperm whale that washed up on Spain’s south coast had swallowed 17kg of plastic waste dumped into the sea by farmers tending greenhouses that produce tomatoes and other vegetables for British supermarkets.” Among the “59 different bits of plastic” it had swallowed, scientists found “thick transparent sheeting used to build greenhouses” as well as “a clothes hanger, an ice-cream tub and bits of mattress.”
These two represent only a small fraction of the whales killed by plastic ingestion or entrapment every year.
Birds, too, even those living in seemingly remote locations, die as a direct result of plastic ingestion. Take, for example, the albatross. Long lived and built for flight, they can spend months aloft traveling nearly a thousands miles a day at high altitudes foraging for food. While in flight inches over or floating on the ocean surface Albatross eat krill, fish and squid (depending on the species of Albatross) and drink salt water. And this behavior puts the Albatross and its young at risk. Because along with water and food, the Albatross ingests pieces of ocean-borne plastic.
In “How the Plastic You Use is Killing Animals on One of the World’s Most Remote Islands,” Malorie Macklin reports that “An estimated 98 percent of albatross have plastic in their stomachs, and 40 percent of chicks die every year due to plastic consumption. Once inside the digestive tract, plastic may fill up the stomach, edging out space for food and water. It can also puncture the internal organs or transport a deadly collection of toxins into the bird. For birds living miles from any major source of pollution, this should be a wake-up call for the damage our use of plastics can have on wildlife.” And because Albatross usually raise only a single chick a year and often skip a nesting season after rearing that chick, losing 40% of the nestlings in a colony annually may pose a serious threat to long-term survivability of these ancient creatures.
Plastic did not exist before we invented it. And plastic did not pollute every continent and every ocean in the world on its own. The responsibility for this environmental catastrophe belongs solely to us. Some hope that vigorous recycling will reduce the “10 million to 20 million tons of plastic [that] enter the oceans every year” Others hope to collect plastic detritus before it makes its way to the ocean. And still others have designed (and are currently testing) devices that might allow the refuse in the world’s great oceanic garbage patches to be corralled and removed.
Hopefully we can do all of the above. And succeed. But consider the following sobering statistics:
• “Around 80% of plastic waste in the oceans originates on land, and recycling rates are poor, with just 9% of plastic in the U.S. recycled, according to the EPA.”
• “Around eight million tons of plastic enter the marine environment each year, and the figure is set to rise. The Ellen Macarthur Foundation estimates that 311 million tons of plastic were produced in 2014, which will double within 20 years, and projects that there will be more plastic than fish in the oceans by 2050.”
• Marine biologists surveying “all five sub-tropical gyres, coastal Australia, Bay of Bengal and the Mediterranean Sea” estimate that “a minimum of 5.25 trillion particles [of plastic] weighing 268,940 tons” currently pollutes the ocean.
• “According to the Blue Ocean Society for Marine Conservation, more than a million birds and 100,000 marine mammals and sea turtles die every year from eating or getting entangled in plastic.” <http://www.salon.com/2007/08/10/plastic_bags/>
To do your part, please begin recycling and finding ways to reduce your use of plastic materials where possible. The lives of endangered California Sea Otters and hundreds of thousands of other vulnerable species around the world depend on our benevolent stewardship.
You can read more about Plastic Pollution and its effect on our planet’s ecosystems in the following articles:
Oceanic Garbage Patches
• Great Pacific Garbage Patch
• The plastic plague: Can our oceans be saved from environmental ruin?
• Mycroplastics [Wikipedia]
• Albatross [Wikipedia]
• Plastic Pollution in the World’s Oceans: More than 5 Trillion Plastic Pieces Weighing over 250,000 Tons Afloat at Sea
• There are 270,000 Tons of Plastic Floating in the Ocean … What Does That Really Mean?
• Plastics in Our Oceans
• Sea Turtles Eating Plastic At Record Rates Amid Surge In Pollution
• Silent Killers: The Danger of Plastic Bags to Marine Life
• Plastic-Filled Albatrosses Are Pollution Canaries in New Doc[umentary]
• For Midway Atoll’s Birds, Plastic is the Main Dish
• Plastics in Paradise: Scientists Collect 60 Tons of Junk Surrounding Remote Hawaiian Islands
• Plastic Bands and other Deadly Debris Killing B.C. Sea Lions
• ESI Field Report: Important Call: Plastics Kill!
• About 99 Percent of the Ocean’s Plastic Has Disappeared. Where It’s Ending Up Should Scare All of Us
• Your Face Scrub Could Be Starving Coral Reefs
• Threats: Bycatch [World Wildlife Fund]
• How the Plastic You Use Is Killing Animals on One of the World’s Most Remote Islands
• For Ocean Animals, ‘Death By Plastic’ Could Be Occurring More Frequently
• How a DVD Case Killed a Whale
• Spanish Sperm Whale Death Linked to UK Supermarket Supplier’s Plastic
• Ocean Plastic Pollution Costs $13 Billion a Year, and Your Face Scrub Is Part of the Problem
• Your Laundry has a Dirty Secret … and It’s Harming Marine Species and Humans!
• Ocean Plastic Pollution’s Shocking Death Toll on Endangered Animals
• Plastic Bags Are Killing Us
Possible Solutions to Plastic Pollution
• 700 Marine Species Might Go Extinct Because of Plastic Pollution. Here Are 5 Ways You Can Help!
• Ocean Plastic Pollution Could Double in a Decade—but There’s a Solution
• 3 Marine Animals Who Are Thrilled About California’s Plastic Bag Ban
• Derelict Fishing Gear Removal Project
• Can These Inventions Save Oceans From Our Plastic Habit?
• The Dutch Boy Mopping Up a Sea of Plastic
• Microbrewery’s Edible Six-pack Rings Create Eco-friendly Alternative to Plastic
• Adios, Pacific Garbage Patch: This Teenager’s Invention Could Clean It Up
• The Plastic Plague: Can Our Oceans Be Saved from Environmental Ruin?