A new hotspot of macro-litter in the Rutland Island, South Andaman, India: menace from IORC

Supralittoral zones of 13 sandy beaches of remote Rutland Island were divided into three zones to identify the litter contamination, its source, pathway of plastic transport to determine the level of macro-litter contamination, and its impact on coastal biota. Owing to the floral and faunal diversity, apart of the study area is protected under Mahatma Gandhi Marine National Park (MGMNP). The supralittoral zones of each sandy beach (between low-tide and high-tide line) were individually calculated from 2021 Landsat-8 satellite imagery before conducting the field survey. The total area of the surveyed beaches was 0.52 km² (5,20,020.79 m²), and 317,565 litters representing 27 distinct litter types were enumerated. Two beaches in Zone-II and six in Zone-III were clean; however, all five in Zone-I were very dirty. The highest litter density (1.03 items/m²) was observed in Photo Nallah 1 and Photo Nallah 2, whereas the lowest (0.09 items/m²) was observed in Jahaji Beach. According to the Clean Coast Index (CCI), Jahaji Beach (Zone-III) is the very cleanest beach (1.74) while other beaches of Zone-II and Zone-III are clean. The findings of the Plastic Abundance Index (PAI) indicate that Zone-II and Zone-III beaches have a low abundance of plastics (< 1), while two beaches of Zone-I, viz., Katla Dera and Dhani Nallah, exhibited a moderate abundance of plastics (< 4) while a high abundance of plastics (< 8) was observed in the rest of three beaches of the same zone. The primary contributor of litter on Rutland's beaches was plastic polymers (60-99%), which were presumed to originate from the Indian Ocean Rim Countries (IORC). A collective litter management initiative by the IORC is essential in preventing littering on remote islands.