Monitoring litter on Arctic and sub-Arctic shorelines: Current status, and next steps for monitoring programs

Plastic pollution is ubiquitous, and the Arctic is no exception. One important step to understand the extent of the problem, and to monitor its impact is to have repeatable, comparable, and relevant measures across time and space that allow for the detection of marine litter trends. Arctic shorelines are a critical part of monitoring efforts. Pan-Arctic monitoring of litter on shorelines is also an essential component to examining global trends. Based on previous work examining litter in some regions of the Arctic, we suggest steps towards more harmonized protocols that include community-based monitoring, crowdsourced science programs, and science team-based surveys that are specific for the Arctic. Specifically, we recommend that shoreline survey sites for long-term monitoring be established where possible and be at least 50 m and surveys carried out with regular intervals of at least twice a year by any type of research team. Criteria for the selection of sites should be grounded in Indigenous and other local community and regional priorities and should result in representation of both remote shorelines impacted by distant-source marine litter and shorelines impacted by more local sources. Results of any Arctic shoreline litter surveys should be made regularly available either through publications which include datasets, and/or accessible databases to promote regional comparisons and trend analysis across the Pan-Arctic.