A lot of plastic ends up in our oceans every year, and animals love to eat it.
For a long time, scientists just assumed the animals ate the plastic because it looked like food. But it turns out, it smells like food, too.
In fact, it smells so enticing that 90 percent of seabirds eat it right now. And by 2050, nearly all of them are expected to dine on it.
When algae coats plastic in the ocean, it gives off the same smell it would have if animals like krill were eating it. Since the birds like to eat krill, they're attracted to the smell of the algae.
One of the big problems with plastic is that it doesn't decompose. Instead, it breaks down into smaller and smaller chunks as it's weathered by the elements.
When an animal eats those chunks, plastic can stay in the animal's system for a long time because its stomach doesn't break the plastic down.