There are lots of theories about why sea turtles or other animals are ingesting plastic. Some have speculated that turtles mistake plastic for food due to its appearance and flow; for example, when a turtle eats a plastic bag that looks like a jellyfish. Sea turtles around the world have been snacking away on plastic for years, but scientists didn’t exactly know why until now.
The University of North Carolina at Chapel Hill’s scientists conducted a study, published in Current Biology, on whether turtles could be attracted to how plastic smells. They presented captive sea turtles with many different smells and found that plastic bags smell like a tasty treat to the turtles because of the bacteria and algae that accumulate on their surface.
Kenneth J. Lohmann, biologist at UNC-Chapel Hill, said:
“This finding is important because it’s the first demonstration that the odor of ocean plastics causes animals to eat them. It’s common to find loggerhead turtles with their digestive systems fully or partially blocked because they’ve eaten plastic materials.”
The team held 15 loggerhead turtles captive for five months as they delivered a series of airborne smells through a pipe. The turtles ignored the scents of water and clean plastic but responded to the smell of ocean-soaked plastics and food by sticking their little noses out of the water to smell. When the turtles smelled bio-fueled plastic, they stuck their noses out three times as long to smell, in the same way they responded to real food. Biofueled plastic is plastic that has been in the water long enough to accumulate microbes, algae, plants, and small animals on its surface.
This study reveals the consequence of how increasing amounts of plastic waste are life-threatening for turtles and other marine animals, including seabirds, fish, and even whales.
Researchers estimate that more than 50% of the world’s sea turtles, and nearly every single seabird, have ingested plastic. This is no surprise, as over 8 million tons of plastic are thrown into the oceans every single year.
Previous research has shown that consuming only 14 pieces of plastic can kill turtles. Young turtles are particularly vulnerable because they like to swim in currents where a significant amount of plastic waste accumulates. Once a turtle ingests the plastic, they are unable to throw it back up again. As a result, the consumed plastic gets stuck in the turtle’s gut and limits its ability to digest and absorb food.
Joseph Pfaller, co-author of the study, explained:
“The plastic problem in the ocean is more complex than plastic bags that look like jellyfish or the errant straw stuck in a turtle’s nose. These are important and troubling pieces to the puzzle, and all plastics pose dangers to turtles.”
Matthew Savoca, one of the study’s authors, believes that this issue is a concern not only for sea turtles but for other animals, too. “Past research suggests that sea birds and some species of fish may also be tricked by their instincts into eating plastic,” said Savoca.
When sea turtles fill up their stomachs with plastic, their bodies are fooled into thinking they’re full, causing them to starve to death eventually. In other cases, harder and sharper pieces of plastic puncture the turtles as they try to swallow it, or it ends up getting caught in their throats, and they choke to death.
This issue extends beyond sea turtles; other marine animals, such as African Sideneck turtles, require special care to prevent the ingestion of plastic and its harmful effects. It is crucial to reduce plastic consumption and prioritize recycling to protect the health and well-being of these vulnerable species, including proper African Sideneck turtle care.
However, there are two simple solutions: reducing plastic consumption and recycling.
