Significant plastic accumulation on the Cocos (Keeling) Islands, Australia

Abstract

For over 60 years, our oceans have been a reservoir for exponentially increasing amounts of plastic waste. Plastic has been documented at all levels of the marine food web, from the deepest oceanic trenches to the most far-flung beaches. Here, we present data on the presence of significant quantities of plastic on the remote Cocos (Keeling) Island group, located 2,100 km off the northwest coast of Australia. From our comprehensive surveys of debris on the beach surface, buried, and beach-back vegetation, we estimate there are 414 million anthropogenic debris items, weighing 238 tonnes, currently deposited on the Cocos (Keeling) Island group. Of the identifiable items, ~25% were classified as disposable plastics, including straws, bags, and toothbrushes. Debris buried up to 10 cm below the surface is estimated to account for 93% (~383 million items) of all debris present on Cocos, the majority of which (~60%) is comprised of micro-debris (2-5 mm). In the absence of meaningful change, debris will accumulate rapidly on the world's beaches. Small, buried items pose considerable challenges for wildlife, and volunteers charged with the task of cleaning-up, thus preventing new items from entering the ocean remains key to addressing this issue.