Fishing gear like nets, fishing line and buoys pose greatest threat to marine wildlife, followed by plastic bags
For the first time, scientists have quantified the impact of plastic waste and trash on marine wildlife around the world.
The study found that nets, fishing line and buoys were found to pose the greatest overall threat to marine wildlife, primarily because of entanglement.
Plastic bags emerged as the second most harmful item as they are often confused for food by marine mammals. Smaller items like balloons were also found to be harmful.
The threats to marine wildlife included entanglement, ingestion, or contamination, suggesting that a comprehensive approach to preventing plastics from entering the ocean is vitally needed.
Scientists at Ocean Conservancy and Commonwealth Scientific and Industrial Research Organisation (CSIRO) released the study in the journal Marine Policy.
The analysis was based on a survey of 274 experts representing 19 fields of study assigned scores for entanglement, ingestions and contamination on a shortlist of items culled from 30 years of data from Ocean Conservancy’s International Coastal Cleanup.
“We now have the best, most comprehensive assessment of trash and plastic waste on some of our most iconic marine wildlife,” said Nicholas Mallos, director of the Trash Free Seas Program at Ocean Conservancy.
“With this knowledge comes the responsibility to seek the most effective solutions to stem the tide of plastics into our ocean. These solutions must range from changing our own behavior as consumers to local efforts like coastal cleanups and product- specific policy, to transformative ways to manage plastic waste at the global scale.”
Eight million metric tonnes of plastic leak into the world’s ocean every year and the amount continues to grow. Without concerted global action, there could be one ton of plastic for every 3 tons of fish by 2025, leading to significant environmental, economic and health issues, Ocean Conservancy said in a press release.
At least 80 per cent of ocean plastic originates from land-based sources.
The study, “Using Expert Elicitation to Estimate the Impacts of Plastic Pollution on Marine Wildlife,” calls for a holistic, cross-sector approach to minimize the overall impact of plastic pollution on the ocean. Product-by-product approaches to reducing ocean plastic impacts alone will not suffice—a key finding from Ocean Conservancy’s Stemming the Tide report that outlines a solution set to reduce ocean plastic pollution by 45 per cent by 2025.
“Our study confirms what many scientists have suspected for some time — that there are likely to be substantial numbers of animals injured or killed by fishing line, plastic bags, balloons and other plastic consumer items every year,” said Chris Wilcox, senior researcher at CSIRO and lead author on the paper.
The study informs the work of the Trash Free Seas Alliance, an effort by Ocean Conservancy to unite industry, science and conservation leaders who share a common goal for a healthy ocean free of trash.
“America’s plastic makers welcome this new study as a contribution to better understanding how litter—and in particular fishing gear—affects the marine environment,” said Keith Christman, managing director of plastics markets for the American Chemistry Council.
“Although the study identified fishing gear as the greatest concern, we look forward to continued work on programs, projects and other collaborations to eliminate the flow of trash into our oceans.”
Through the American Chemistry Council, America’s plastics makers have helped lead the development of the plastics industry’s “Global Declaration on Marine Litter,” which has been signed by more than sixty plastics associations in 34 countries. Today, more than 185 projects focused on researching, preventing or reducing marine debris are underway around the globe.