Scientists have released an alarming new study indicating that seabirds are behaving in a bizarre manner, and one that is hazardous to their health: gobbling up plastic debris in the ocean because it smells like food to them.

Seabirds such as albatrosses and petrel use their olfactory senses to track down krill, their main food. The way they find krill is to detect the smell of dying algae, indicating that krill are feeding. But scientists have found that algae also sticks to plastic that is floating in the ocean, and it dies and gives off a similar smell, drawing seabirds in who eat the plastic, according to the study, put out by UC Davis and published in the journal of Science Advances.

Scientists made the discovery by taking three types of plastic most commonly found in the ocean and putting it in a mesh bag, tying it to a buoy to prevent it from floating out to sea. Three weeks later, they pulled the plastics in to find lots of algae that was dying and giving off the scent, likely drawing seabirds to it.

“It’s important to consider the organism’s point of view in questions like this,” said lead author Matthew Savoca, who performed the study as a graduate student in the lab of UC Davis professor Gabrielle Nevitt and who is with the Graduate Group in Ecology. “Animals usually have a reason for the decisions they make. If we want to truly understand why animals are eating plastic in the ocean, we have to think about how animals find food.”