Densities of neuston often not elevated within plastic hotspots territory inside the North Pacific Garbage Patch

Abstract

The North Pacific Garbage Patch, located in the eastern part of the North Pacific subtropical gyre, contains vast amounts of floating plastic debris. Research over the past decades has mainly focused on assessing the extent of plastic pollution in this oceanic region. However, the North Pacific subtropical gyre is also home to the surface-associated pelagic community known as neuston. To date, the dynamics of this ecosystem and its vulnerability towards environmental pollution and anthropogenic impacts remain poorly understood. While removing plastic debris afloat at sea can reduce negative impacts of plastic pollution on neuston and marine life in general, concerns have been raised that cleanup efforts could have an adverse effect on neuston due to potential co-accumulation of neuston and plastic at the sea surface. Here, we provide the most comprehensive assessment of neuston abundance in the eastern North Pacific Ocean and its relation to the distribution of floating plastic debris (0.05-5 cm in size) based on a first year-round survey. Our results reveal that neuston taxa inside the North Pacific Garbage Patch often show similar or lower abundances in areas with particularly high densities of floating plastic debris compared to the wider garbage patch. Targeting open-ocean cleanups on such plastic hotspot territories inside the garbage patch can therefore minimize interactions with neuston during cleanups, thus maximizing their net environmental gain. We further discover that neuston depicts substantial seasonal variability, which needs to be considered when assessing impacts on neuston.