How much plastic does it take to kill a sea turtle?

How much plastic does it take to kill a sea turtle? According to new research, it does not take much.

A study published in the journal Nature On Thursday, sea turtles have a 50% chance of mortality once they ingested 14 pieces of plastic.

This means that researchers expect that 50% of marine turtles that have consumed this amount of plastic die. Scientists also found that if a turtle had at least 226 pieces of plastic in his intestines, then he was certain that she would die.

Scientists have stepped up their efforts to examine the precise impacts of ocean pollution on marine life, now that plastics have been found to affect 700 different marine species, according to New Student Principal Investigator Britta Denise Hardesty .

To calculate the impact, a team of scientists led by Hardesty examined data on about 300 necropsies of turtles in Australia whose deaths were recorded in three different categories: non-plastic, unknown cause, plastic-related.

Using these distinctions, researchers were able to compare unknown and plastic-related deaths with plastic-related deaths to determine what is considered a normal amount of plastic ingested by turtles.

Within the sampled population, the amount of debris found in the bowels of turtles ranged from a 329-piece coin.

However, not all scientists agree with the findings of the study.

"I'm more optimistic than the authors," said biologist Jennifer Lynch, who is not affiliated with the study, in an email.

A study she conducted in 2017 found that turtles are not affected by small amounts of plastic debris or even after ingesting 200 to 300 pieces of plastic.

"All studies have some sort of bias, my study was biased towards turtles that were healthy and actively feeding when they drowned in a hook," Lynch said.

"[The present] The study is skewed in favor of stranded turtles that have died from various causes, the causes of which are often unknown. "

That said, the new study adds to a growing number of scientific publications on plastics and turtle mortality.

Another important discovery in the study concerned the age of turtles affected by debris.

Researchers also found a significantly greater amount of plastic in juveniles than in adults. For them, this meant that adults are less likely to ingest plastic by mistake than younger ones.

Brendan Godley, a conservation scientist not affiliated with the study, said in an email that this research indicated the likelihood that plastics pose a major threat to the youngest, suspected, but unknown life stages.

"This is particularly worrying because plastic pieces and baby turtles are both likely to be clustered in similar areas," he explained.

But that does not mean that turtles are in danger of extinction. Sea turtle populations respond well to conservation efforts.

It just says that if ocean pollution gets worse, sea turtles are in danger, Godley said.

While the exact amount of plastics leading to death can be hotly debated, scientists have been aware that plastic has been a threat to sea turtle populations for some time. In fact, sea turtles were among the first animals to ingest plastic.

And with the rise of plastic deposits in the ocean, the threat posed by debris to marine life has extended well beyond sea turtles and will continue to grow if a solution is not found.