Some of the most heartbreaking encounters I have had while scuba diving in the Sea of Cortez have occurred when marine life has met with human garbage. I have seen dolphins drowned in ghost nets and sperm whales dragging hundreds of feet of discarded monofilament net (which was thankfully removed by scuba divers). One particular incident stands out for me.
We were headed out to dive at Isla San Pedro Nolasco from San Carlos. Excitement on the boat grew at the sight of a sea turtle bobbing its head out of the water a couple of miles from the island. As the boat drew closer, we were dismayed to see that the turtle was hopelessly entangled in fishing net, and was struggling to keep its head above water. Several of us jumped in with snorkeling gear, dive knives, and shears to attempt to free the turtle.
When we reached her it was apparent that we couldn’t safely free her in the water. Line was wrapped in her mouth, it had cut deeply into her skin, and one of her forelimbs had been severed completely. She had obviously been dragging the line for many days, as the severed limb had already begun to heal over, although it was still raw near where the bone had been cut. She was brought on board and we began to carefully cut away the line and clean her wounds. She was at least lucky that we had both a marine biologist and a veterinarian on board.
At the time, there was no sea turtle rescue facility nearby. Hopefully this has changed, or will soon. In fact, turtles are regularly poached in the area and sold for food. We decided that her best hope for survival would be to release her at San Pedro Island, where there is plentiful food in shallow waters, and she would be farther from terrestrial predators, including poachers. We covered her in moist towels to cool her and keep her calm. When we reached the sheltered bay at lighthouse point, we hoped we had done all we could and slid her into the water.
She cruised the bay for a little while and disappeared around the North point. Without intervention, she would have surely perished. Plastic fishing gear remains intact for decades, possibly even centuries, all the while, drifting and continuing to kill any organisms that might become entangled. At least with the netting removed, the turtle had a chance. We hope she survived.
While entanglements are an obvious and easily visualized hazard, plastic debris represents an even more insidious threat. Marine life has swum in plastic-free seas for millions of years. They do not have the capability to identify plastics as something not to be eaten. To a sea turtle, plastic bags look just as tasty as the jellyfish that sea turtles feast on. The result is choking and intestinal blockages. Whether the animal chokes outright, or slowly starves to death, the end result is the same.
My longtime friend Wallace “J.” Nichols, PhD, of the California Academy of Sciences recently coauthored an editorial with Colette Wabnitz, PhD, of the University of British Columbia in the Marine Turtle Newsletter, regarding the effects of plastic debris on turtles. I am reprinting the press release about the article below. It does a great job of summarizing the full article, which is a thorough and very informative piece, compiling many years of research by numerous individuals and agencies. I definitely recommend reading the full editorial if you are interested. The PDF can be accessed at seaturtle.org.
Reading these articles, you will likely be astounded at how much plastic ends up in the marine environment. There are a lot of good tips in the articles on how we can all help. These can be generally summed up as four basics: Minimize your use of disposable plastics when you can. Secure your plastics when on-board or at the beach. Dispose of your waste properly. When visiting the ocean, try to leave it a little cleaner than when you arrived.
So with no further ado, here is the release. Please consider visiting seaturtle.org for more info on how we can all help to keep the oceans safe, both for our own enjoyment, and the health of our aquatic friends.
Our Plastic Food Chain -or- The Turtle Who Pooped Plastic
As ocean pollution experts meet in Hawaii, disturbing new report chronicles effects of decades of plastic pollution on sea turtles—and what we can do about it.
Honolulu, 22 March 2011
In 2009, marine biologists with Disney’s Animal Programs in Melbourne Beach, Florida, discovered a green sea turtle that was having trouble digesting food. They found that a piece of plastic had lodged in the turtle’s gastrointestinal tract. When biologists removed the obstruction, the turtle defecated 74 foreign objects in the subsequent month. Among the items documented were four types of latex balloons, five different types of string, nine different types of soft plastic, four different types of hard plastic, a piece of carpet-like material, and two tar balls to boot.
The list of items from this one turtle read like a catalog of a growing and deadly concern for virtually all marine animals—single-use plastics are having a lethal effect on animals living in the sea.
Experts on plastic pollution from around the world, determined to solve this growing problem, have gathered this week for the Fifth International Marine Debris Conference in Honolulu, Hawaii, a mecca for green sea turtles.
Now, in a recent editorial published in the Marine Turtle Newsletter, marine biologists Colette Wabnitz, PhD, of the University of British Columbia and Wallace “J.” Nichols, PhD, of the California Academy of Sciences, lay out the entire disturbing history of plastics in the ocean, from the first scientific report to the latest surveys, to call attention to the concerns from 1972 to today. The report is grim, but provides a ray of hope in the form of proactive steps that can and should be undertaken to curtail overproduction and careless discard of single-use plastics.
The authors were careful to acknowledge that certain plastics have done much good in the world. The report firmly lays the blame at the feet of so-called “disposable” plastics: commonly used beer cups, water bottles and caps, grocery bags, plastic utensils, and so forth, intended to be used just once and thrown away. While these plastics are cheap and convenient, they are also durable and buoyant—making for a potent and deadly combination in the water
Though plastics like these do break down from exposure to sunlight and other elements, the molecules of plastic never fully biodegrade—they just break into smaller and smaller pieces but never completely disappear. Eventually, many of these small particles get blown or washed into tributaries that feed rivers, which flow to the ocean where plastics coalesce in ocean currents. Here they swirl in the eddying currents forming a sort of plastic soup where they float virtually forever and are often—the whole pieces and broken bits—ingested by the creatures of the sea. Once in the guts they can do great harm, or even kill, animals such as sea turtles.
Among the more startling facts reported is that 1 billion single-use plastic bags are distributed free of charge every day, of which an estimate 0.2-0.3% make their way to the ocean. Even that small percent means hundreds of millions of bags each year are left to float in the sea. In particular, the crisis has had a deleterious effect on sea turtles, which mistake the floating bags for jellyfish, a favorite food.
All seven species of sea turtle are listed as endangered on the World Conservation Union’s “Red List” of species in danger of extinction, a situation made even more urgent for many animals by plastic pollution.
“Last year I counted 76 plastic bags in the ocean in just one minute while standing in the bow of our sea turtle research boat at sea in Indonesia”, reports Dr. Wallace J. Nichols, Research Associate at the California Academy of Sciences and coauthor of the review. “The science is becoming crystal clear: sea turtles and plastic pollution don’t mix well. Sea turtles have spent the past 100 million years roaming seas free of plastic pollution, and are now sadly the poster animal for impacts of our throw away society on endangered species”, states Nichols.
Other facts reported by Wabnitz and Nichols and explicitly illustrated in the accompanying photo library, include:
• Worldwide, plastic pollution is adding to the stress on endangered ocean wildlife, like sea turtles;
• Plastic can be ingested by or entangle sea turtles and can physically interfere with their nesting activity on beaches when it accumulates in large amounts;
• Approximately half of all sea turtles surveyed had ingested plastic items; and,
• Micro-plastics are accumulating in molluscs and crustaceans sea turtles eat.
The authors were not without suggestions for corrective measures to ameliorate or end the plague of plastics in the ocean. In addition to broader policy efforts recommended by the authors, were simpler—”off-the-shelf”—personal behavior solutions, including:
• Avoiding plastic-bottled beverages;
• Buying products with minimal or reusable packaging;
• Buying in bulk whenever possible to reduce packaging;
• Buying used items;
• Seeking out reusable shopping and produce bags like those made from renewable sources (e.g., natural fibres) and always bringing them along;
• For coffee and or tea – bring your own mug;
• For food – bring your own container.
“Sea turtle researchers and conservationists have a unique role to play in our cultural evolution away from plastic pollution, as we have watched the havoc the surge of plastic has caused first hand”, notes Dr. Colette Wabnitz of the University of British Columbia.
“Sea turtle researchers from around the world have been submitting photos of interactions with plastic to the Image Library on Seaturtle.org. Given the amount of disposable plastic I see alongside the road everyday and the garbage my kids pick up whenever we go to the beach, the results are not surprising”, added Dr. Michael Coyne, founder and director of SeaTurtle.org.
The pdf of the report and a collection of images from around the world depicting in excruciating detail the impact of plastic on sea turtles can be found at: http://www.seaturtle.org/plasticpollution/