Abstract
Despite an increasing research conducted on ocean plastic pollution over the last decade, there are still large knowledge gaps in our current understanding of how floating plastic debris accumulating in subtropical oceanic gyres may harm the surface-associated pelagic community known as neuston. Removing floating plastic debris from the surface ocean can minimize potentially adverse effects of plastic pollution on the neuston, as well as prevent the formation of large quantities of secondary micro- and nanoplastics. However, due to the scarcity of observational data from remote and difficult to access offshore waters, neuston dynamics in subtropical oceanic gyres and thus the potential impacts of plastic pollution as well as of cleanup activities on the neuston remain uncertain. Here, we provide rare observational data of the relative distribution of floating plastic debris (0.05–5 cm in size) and members of the neuston in the eastern North Pacific Ocean. Our results reveal that the dominant neustonic species co-occurring with high concentrations of floating plastic debris in the North Pacific Garbage Patch (NPGP) such as Porpita porpita, Halobates spp., pteropods, isopods, heteropods, and crabs depict either a low atmospheric drag due to physical attributes or a potential plastic-associated fitness benefit such as increased surface area for oviposition and structure for habitat. We further observe relatively higher plastic to organism ratios inside the NPGP for most target species compared to waters outside the NPGP. The findings presented here provide a first observational baseline to develop ecological models that can help evaluate the long-term risks of plastic pollution and of offshore cleanup activities for neuston in the eastern North Pacific Ocean. We further suggest that offshore mitigation strategies aiming at removing floating plastic debris from the ocean surface need to evaluate both, the direct impact of neuston bycatch during plastic removal on neuston population dynamics, as well as the potential benefits of reducing the negative effects of plastic pollution on the neuston.
Highlights
Pollution of our oceans by plastic debris is widely recognized as a major environmental problem
High concentrations of floating plastic debris are observed in the surface ocean of remote subtropical oceanic gyres, accumulation zones known as ocean garbage patches, where plastic concentrations can exceed one million pieces per km2 for fragments >0.5 mm and hundreds of kilograms per km2 (Cózar et al, 2014; Eriksen et al, 2014; Van Sebille et al, 2015; Lebreton et al, 2018)
The data available to date indicate that most of the plastic mass in the North Pacific Garbage Patch (NPGP) is still afloat in the surface ocean (Egger et al, 2020b) and that the plastic debris accumulating in these offshore waters could persist at the sea surface for decades (Lebreton et al, 2019)
Summary
Pollution of our oceans by plastic debris is widely recognized as a major environmental problem. The characteristics of geographically remote ecosystems such as the subtropical oceanic gyres or the underlying deep-sea, which have evolved in relatively constant environmental conditions with little human influence and which often contain a large number of endemic and sensitive species suggest that they might be especially vulnerable to adverse effects of plastic pollution (Horton and Barnes, 2020). Due to their remoteness, the subtropical gyres remain severely under sampled (Karl, 1999; Karl and Church, 2017). The ecosystem structure and dynamics in these offshore waters, as well as the impacts of plastic pollution and of associated rafting of invasive species on the fitness of individual endemic organisms or possible population-level impacts are still poorly understood
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
