Turtles mistake smell of plastic for food

Plastic gauze in the sea could attract turtles because of its smell, according to a study.

A team led by joseph pfaller of the university of florida in gainesville reports in the journal "current biology" that sea turtles react to the smell of plastic on which microorganisms and other creatures have accumulated in the same way as they do to fragrances in food. "This suggests that turtles are attracted not only to the look but also to the smell of plastic gauze," pfaller is quoted as saying in a news release.

Turtles die again and again from eaten plastic or become entangled in mud floating in the sea. Until now, scientists have assumed that animals confuse plastic with prey because of its appearance, for example, plastic turkeys with jellyfish.

Researchers exposed 15 young, captive-reared loggerhead turtles (caretta caretta) to certain odors and then observed their behavior. The odors were passed through a tube over a small tank. In addition to the smell of fish and shrimp, they also include the smell of plastic on which microbes, algae, plants and small animals have deposited. Deionized water and clean plastic were used as control odors.

According to the researchers, the behavior of the turtles was significant: compared to the control odors, they kept their noses out of the water more than three times longer when the researchers passed the smell of food or plastic with debris over the water. "We were surprised that tortoises reacted to smells from plastic with deposits with the same intensity as to their food," says pfaller. Future studies now had to find out what kind of compounds on plastic led the turtles on the wrong trip.