Lindsay Young of the University of Hawaii and colleagues attached location trackers to adult Laysan albatrosses on Oahu and on Kure Atoll, located 1,300 miles northwest of Oahu.
The researchers were curious to see how the foraging patterns differed at the two locations during the egg incubating and early chick-rearing season -- when the birds have to return regularly to the nest -- and afterward.
They also analyzed the pellets regurgitated by the chicks. "We noticed that there was a lot more plastic in the ones from Kure Atoll than from Oahu," Young said.
The monitors showed that the Kure Atoll birds spend a lot more time over the Western Garbage Patch, a zone off Japan where ocean currents have trapped large amounts of garbage, than the Oahu birds spent over the corresponding Eastern Garbage Patch between Hawaii and California.
Although the Kure Atoll chicks regurgitated 10 times more plastic than the Oahu birds, the pellets had about the same amount of real food.
"The fact that they cough them up usually means the chicks are going to be OK," Young noted. "It is the ones they can't cough up that are the problem."