Rapid assessment is a visual estimation survey method used to understand the standing stock of coastal debris. Through this method, we have been able to ascertain the volume, hotspots of distribution, and major types of debris. Averaging over four surveys conducted between 2018 and 2019, the mean amount of coastal debris in Taiwan was estimated to be 406.6 kg/km, with plastic bottles, foamed plastics, and fishing nets and ropes being the three most abundant types.
The results showed a highly aggregated pattern of debris, similar to what is observed in Japan and South Korea. This suggests that the debris is concentrated in few, highly polluted areas and that cleanup efforts should prioritize these hotspots in order to reduce plastic pollution. From 2018 to 2022, we continued to conduct the rapid assessment survey, and the data obtained thus far indicates that the standing stock of coastal debris has decreased by 46% since 2019. The findings were published in Science of the Total Environment and Regional Studies in Marine Science.