From Paper Parks to Real Protection: Ecological Performance of No-Take Zones in Aceh Besar, Indonesia

This study aimed to quantify the ecological responses of coral reef habitats and fish communities within four adjacent no-take zone (NTZs): Lhoknga, Lampuuk, Bunta Island, and South Batee Island in Aceh Besar Marine Protected Area, Indonesia, and to test whether protection implemented between 2018 and 2024 has improved ecosystem condition. Using a before-and-after comparative design, benthic cover and reef fish community structure were quantified from field surveys. Field survey data were integrated with satellite-derived water quality parameters, including sea surface temperature and nutrients. Results revealed spatial heterogeneity in recovery trajectories, with no statistically significant aggregate changes in live coral cover, fish abundance, or fish biomass across the NTZ network. South Batee Island exhibited exceptional benthic recovery but a substantial decline in fish biomass, indicating a critical disconnect between habitat improvement and resource protection, driven by weak enforcement. In contrast, only Bunta Island maintained concurrent positive trends in both habitat conditions and fish biomass. Across all sites, rising sea surface temperatures imposed chronic thermal stress. These findings challenge the assumption that regulatory designation of no-take zones guarantees ecosystem restoration in Aceh Besar, revealing instead that enforcement intensity, habitat quality, and climate stress determine NTZ effectiveness to a far greater extent than legal status alone, underscoring the urgent need to shift management focus from nominal protection to active compliance monitoring and adaptive management.