Sea turtles may confuse the smell of ocean plastic with food
To a sea turtle, plastic debris might smell like dinner. As the plastic detritus of modern human life washes into oceans, marine creatures of all kinds interact with and sometimes eat it (SN: 11/13/19). Recent research suggests that this is no accident. Plastic that’s been stewing in the ocean emits a chemical that, to some seabirds and fish, smells a lot like food (SN: 11/9/16). That chemical gas, dimethyl sulfide, is also produced by phytoplankton, a key food source for many marine animals. Now, scientists have determined that loggerhead sea turtles may also confuse the smell of plastic with food, according to a study published March 9 in Current Biology. Over two weeks in January 2019, 15 captive loggerheads in tanks were exposed at the water surface to a slew of scents, including the largely neutral scent of water as a control, of food such as shrimp and of new and ocean-soaked plastic. The turtles (Caretta caretta) largely ignored smells of water and clean plastic. But when the...