Efficient Beach Litter Monitoring: Accelerated Surveys of Pollution Hotspots—A North African Case Study

Marine litter is a critical environmental issue, with beach litter being its most visible indicator. Despite severe pollution on Mediterranean beaches, Tunisia currently lacks a national beach litter monitoring program. To address this gap and support the development of such a program, particularly at pollution hotspots like urban beaches, we conducted a one-year study on six Tunisian beaches. We employed an innovative, accelerated multiple 10 m transect method tailored to highly polluted beaches, focusing on macro-litter (>2.5 cm). This method significantly reduces survey time compared to the standard 100 m approach while maintaining comparable pollution metrics, offering a practical and efficient solution for areas with high litter density. Our findings reveal an average litter density of 1.01 ± 1.08 pieces/m2, with higher pollution in urban areas. Based on the Clean Coast Index (CCI), two beaches were classified as extremely dirty, one as dirty, two as moderately clean, and one as clean. Plastics (59.2%) and cigarette butts (21.1%) were the most prevalent pollutants, with single-use plastics comprising 52.5% ± 5.3% of total litter. Most of the litter (60.6%) originated from shoreline activities and poor waste management. These findings underscore the urgent need for a long-term national beach litter monitoring program. The integration of our accelerated transect method would enable efficient, effective surveys on highly polluted beaches, providing critical data to address litter sources and support targeted strategies for mitigating pollution and protecting Tunisia’s coastal ecosystems.