When veterinarians at the Taronga Zoo in Sydney rescued a tiny turtle from a nearby beach, the first thing they noticed was that it had one of its back flippers chomped off by something. But then they soon noticed something even more shocking: the small marine creature was pooping plastic — and nothing but plastic. It did so for six days straight until the turtle finally expelled most of the plastic fragments from its intestines. The rescued turtle is now doing well, but its ordeal illustrates how rampant plastic pollution is in the world’s oceans.
“He defecated six days of plastic. No feces came out, just pure plastic,” veterinary nurse Sarah Male said during a video posted on the zoo’s video.
“It was all different sizes, colours, and compositions. Some were hard, some were sharp, and with some, you could tell the plastic had writing on it. This is all some of these poor little things are eating. There’s so much plastic around they’re just consuming it as their first initial food,” she said.
When it doesn’t end up in landfills or litters the terrestrial environment, plastic waste often ends up in the ocean, the ultimate garbage sink. According to the WWF, human activity is responsible for dumping over 8 million tonnes of plastic into the sea every year. At this rate, the amount of plastic could outweigh all fish by 2050.
Plastic can be found across all oceans and at virtually all depths — and this includes the Mariana Trench, the deepest point on Earth, where researchers found a plastic shopping bag, exactly like the one you’d find in grocery stores.
The problem with plastic is that it doesn’t really decompose — it simply breaks off into smaller and smaller pieces, accumulating in the oceans. Plastic pollution is already one of the most serious threats to ocean ecosystems. Previous studies have found that there are trillions of plastic pieces in oceans, and the ocean sediments are already a plastic cemetery.
Plastic pollution threatens wildlife in a number of ways. First, through ingestion — we’ve seen many times the dramatic effects ingested plastic can have on unfortunate creatures. Microplastic can even be ingested by zooplankton and then transferred up the food chain, including to some species of economic importance, which means that ultimately, we humans may be ingesting the plastic ourselves.
Sea turtles are some of the most vulnerable marine creatures in the face of plastic pollution. Plastic bags look very similar to jellyfish and fishing nets often look like tasty seaweed, so turtles think they’re consuming some of their staple foods when really they’re welcoming harmful substances into their digestive tract. Research conducted by the Commonwealth Scientific and Industrial Research Organisation (CSIRO) and the University of the Sunshine Coast (USC) found that a turtle had a 22% chance of dying if it ate just one piece of plastic. Once a turtle had 14 plastic items in its gut, there was a 50% likelihood that it would die.
Miraculously, the tiny hatchling rescued at Taronga Zoo thankfully survived, but it was also very, very lucky. The hospital at Taronga where he was cared for looks after up to 80 turtles a year, many of whom are admitted with injuries after becoming entangled in fish nets.
While this incident serves to illustrate the numbers and stats we often gloss over from studies, there is sometimes also good news. Recently, researchers at CSIRO in Australia found that local action does actually work, concluding that the amount of plastic pollution on the country’s coast had decreased by up to 30% on average thanks to programs from local authorities.
Tibi is a science journalist and co-founder of ZME Science. He writes mainly about emerging tech, physics, climate, and space. In his spare time, Tibi likes to make weird music on his computer and groom felines.