Reference: Gacutan, J., Johnston, E.L., Tait, H., Smith, W., Clark, G.F.(2022). Continental patterns in marine debris revealed by a decade of citizen science. Science of The Total Environment 807: 150742.
Monitoring marine debris
Marine debris or litter introduced into the ocean by humans is a known problem. We see it accumulating on our shorelines, posing a threat to wildlife, and detracting from maritime activities. The best way to effectively manage marine debris is to first determine where the debris is coming from and what types of debris are a problem (single use plastics, fishing gear, etc.). This requires extensive monitoring efforts. Citizen science projects encourage everyday people to get outside and collect information in the name of science. In this case, shoreline cleanups are not only a service to the local community and wildlife but can be used to record the types and amounts of debris found along the shore. Researchers can use the information collected to find where the marine debris came from and determine the best tactic to limit more pollution. However, because citizen science projects don’t collect data in a standardized way, it is often difficult to compare the data collected across projects.
Making the data work
This study, conducted by researchers in Sydney, Australia in association with the Tangaroa Blue Foundation, sorted through a database of cleanup efforts along the entire shoreline of Australia. Datasets collected by different organizations or groups (e.g., schools or nonprofit organizations) may not be comparable. The volunteers may inadvertently introduce bias by focusing on specific types of debris or collecting more easily visible debris. These inconsistencies can affect data quality and make it difficult to figure out what and how much marine debris is found across large regional and temporal scales. For these reasons, the researchers limited their analysis to cleanups on ocean-facing, sandy beaches completed in one day without any missing information. Cleanups that didn’t remove all marine debris within the one day were omitted. The number of debris collected per day was used to estimate the rate that debris has accumulated on sandy, Australian beaches over the past decade.
Findings
The research shows that the most debris accumulated on the east coast of Australia, outside of major cities, suggesting that there are higher levels of pollution in urban areas. Unsurprisingly, plastic waste made up most of the trash collected because of littering. Hard plastic container lids, Styrofoam containers, and cigarette butts were among the most common types of debris found.
While this study provides us with a better idea of what kinds of trash need to be regulated, the methods for filtering quality datasets out of a large citizen science database are instrumental for big-picture monitoring efforts. The filtered database can be used to compare sampling strategies across groups (businesses, schools, non-profit organizations, individuals) to help improve citizen science techniques. While the data may not be perfect, citizen data collection can help fill in the gaps with monitoring efforts as it is logistically and financially impossible for scientists to cover the necessary areas alone. These data inform the public and can lead to proper management efforts including bans on certain products, or regulations on both littering and the industries contributing to shoreline debris. So don’t be afraid to pick up some trash and get involved in a community cleanup effort. Your local scientists and wildlife will thank you.
I am a PhD candidate at the University of Connecticut-Avery Point exploring the dynamic interactions of microplastics and suspension feeding invertebrates. Through both field and laboratory work, I am working to understand which kinds of microplastics (different shapes, sizes, compositions) oysters, mussels, tunicates, and slippersnails consume and determine which species can be used to monitor microplastic pollution in our coastal waters. When I am not working on my research, I enjoy hiking with my husband and pup, being near or in the water, and spending time with family and friends.
