Decadal changes in plastic litter regurgitated by albatrosses and giant petrels at sub-Antarctic Marion Island. (October 2020) - Perold, Vonica
Abstract: Plastic ingestion by seabirds is an efficient way to monitor marine plastics. We report temporal variation in the characteristics of marine litter regurgitated by albatrosses and giant petrels on sub-Antarctic Marion Island between 1996 and 2018. Both fishery and other litter peaked during the height of the Patagonian toothfish fishery around the island (1997–1999). Comparing the two subsequent decades of reduced fishing effort (1999–2008 and 2009–2018), fishing litter decreased while other litter increased across all species. Litter increased most in grey-headed albatrosses, followed by giant petrels and wandering albatrosses. Similar ranked responses were found in the same species at South Georgia, but non-fishery-related litter has increased faster in the Indian Ocean than the southwest Atlantic, indicating regional changes in litter growth rates. These seabirds' regurgitations provide an easy, non-invasive way to track changes in oceanic litter in a remote area that is otherwise difficult to monitor. Highlights: Fishery-related litter decreased with reduced local fishing effort. Non-fishery litter items increased on Marion Island between 1996 and 2018. Increase within species is faster in the Indian than South Atlantic Ocean. Increases in most species exceed the rate of growth in global plastic production. Albatrosses and petrels are useful indicators to track changes in marine litter.