In this study, the scientists used plastic beads of the type used in bottles, bags, textiles and hundreds of applications, ranging from four to six millimeters in diameter. After the microplastics had been in the ocean for about three weeks, dimethyl sulfide was found in the water and air around them in concentrations high enough that these types of birds may be able to smell, the scientists found, using tools that are otherwise meant for measuring sulfur in beer or wine.

The study suggests that the odor of dimethyl sulfide on or around marine plastic debris is “maladaptive foraging behavior” — that the birds are using their evolutionary traits to forage for food in ways that might be bad for them, causing problems like chemical toxicity or obstruction. According to the study, a recent projection model concluded that more than 99 percent of all seabird species will have eaten plastic debris by 2050.

Dr. Nevitt said that the study could have implications for other marine animals. Those that eat similar species to these birds — like baleen whales — or those that may also be attracted to dimethyl sulfide — like sea turtles — could be at risk. The researchers hope the study will help determine strategies for how to fight this growing environmental problem, as plastic pollution increases in the ocean.

“Fifty or 60 years ago, there was no plastic in the ocean,” Mr. Savoca said. Now, estimates hover in the hundreds of millions of tons. “We’re changing the world so rapidly that these animals can’t evolve rapidly enough to keep up.”