A floating island of plastic-laden trash “lives” east of North Carolina in the Sargasso Sea region in the Atlantic Ocean. Named the Atlantic Ocean Garbage Patch, it’s not as big as its Pacific Ocean cousin, but it poses the same serious health risk to animals, birds, other marine life and humans.
The National Oceanic and Atmospheric Administration (NOAA) tells us that the Sargasso Sea is the only sea without a land boundary. It is defined by ocean currents, so the Sargasso Sea’s borders are dynamic and reflect seasonal variations. The Gulf Stream, about 50 miles off the North Carolina coast, forms the Sargasso Sea’s western boundary. Bermuda is the most identifiable prominent land mass within the Sargasso Sea region.
NOAA said: “The Sargasso Sea is named for a genus of seaweed called sargassum, which floats freely and reproduces by vegetative fragmentation on the high seas. Sargassum provides a home to an amazing variety of marine species. Turtles use sargassum mats as nurseries where hatchlings have food and shelter.”
The dark plant matter also absorbs warmth from the sun, providing healthy “thermal benefits” to young turtles.
Baby loggerhead turtles, for example, are programmed to head toward the Sargasso Sea as soon as they enter the surf. New research, however, is showing the turtles are dying because they are ingesting plastic trash that is trapped in the Sargasso Sea ocean gyre.
A gyre is a large system of circular ocean currents formed by global wind patterns and forces created by Earth’s rotation. The water circulates in a slow spiral. Winds are light and the currents tend to push any floating material into the low-energy center of the gyre. The sea garbage is in a state of never-ending rotation.
NOAA scientists refer to the gyre contents as “trash soup, a collection of pelagic plastic particles, consumer products and sludge. The plastic particles seen of the surface of the water form just a portion of what’s there, since plastic also gets pushed down below the surface.
“Since plastic doesn’t biodegrade, what is thrown into the ocean will always be there. Trillions of these plastics get trapped in the floating trash pile,” NOAA contends. Toxic chemicals that do not dissolve in water are there, too, “absorbed by plastic just like a sponge.”
Hakai Magazine, published in Victoria, British Columbia, Canada, seeks to protect the world’s coastal ecosystems. An article from a December 2018 issue, authored by Allison Salerno, created quite an “environmental uproar” with its headline: “Turtles’ Tummies Found Clogged with Plastic.”
She reported: “Tiny pieces of plastic in the ocean are killing juvenile loggerhead turtles…threatening the survival of the species.” It’s everywhere in the sargassum where the loggerhead turtles forage for food.
Research scientist Evan White of the University of Georgia at Athens and colleagues examined the gastrointestinal tracts of 52 turtles that died at only days or months old and found that 48 contained plastic, Salerno reported. The plastic bits, which were up to a millimeter wide, were sometimes lodged in the turtles’ stomachs or narrow, winding intestines, blocking the passage of food, causing the turtles to starved, she wrote.
Dr. Charles Manire, a veterinarian at the Loggerhead Marinelife Center in Juno Beach, Fla., was a partner in the research project. He and his colleagues collected 97 “wash backs” – young turtles that made it offshore and into the sargassum but were blown ashore and stranded by a storm or high winds two to six months later.
Dr. Manire’s team rehabilitated and released 45 of these turtles after treating them and giving some of those with suspected plastic blockages an enema. The dead turtles were frozen to preserve their tissues, enabling researchers to perform necropsies during which they found the plastic in their gastrointestinal tracts. The plastic was just a tiny percentage of their body weight, but enough to kill them, Salerno said.
When Dr. Manire began working as a marine veterinarian 25 years ago, he told Salerno that he would occasionally see plastic in turtles. Now, “it’s no longer a question of if they have plastic, it’s a question of how much.”
Loggerheads and other sea turtles have always had a high mortality rate: one in every 1,000 loggerheads is estimated to survive to maturity, even without plastic pollution to contend with, Salerno said.
Dr. Manire thinks the death rate now is much higher. “It may be that the one in 1,000 number is now one in 100,000 or one in a million,” he says.
Findings from these two scientific studies show how serious the dangers of microplastic are to the survival of loggerhead turtles, says Dr. Jeanette Wyneken of Florida Atlantic University in Boca Raton, Fla.
In understated tones, she told Salerno that plastics are “considered a pretty substantial threat to survival of the species.”
Enough is enough. The loggerhead turtles are pleading for our help – for us to come to their rescue.