Microplastic accumulation visually and fluorescently undetectable within deepwater corals of the remote equatorial Pacific

Abstract

Microplastic abundance in aquatic environments is a well-established phenomena, with the potential to disrupt ecological processes, including food webs and vector diseases via contaminated water and sediments. With the call for increasing ocean protection in remote and deep-waters, it is important to establish baselines of relative contamination, and to identify whether or not there are places relatively free from microplastic impact. Deep-sea corals are heterotrophic ecosystem engineers that have the potential to capture and ingest microplastic particles. In this study, we asked whether or not deep-sea corals in humanly remote, fully-protected, locations demonstrate evidence of microplastic ingestion using visual and fluorescence-enabled techniques. We found no strong evidence for microplastic accumulation. Despite these specific results, maintaining plastic-free environments in remote deep-sea systems will benefit from increased protections that limit or prevent anthropogenic activities. As such, open ocean and deep-water marine protected areas should consider including decreased pollution risk among their potential benefits.