Acoustic sensors logged 3,548 blast-fishing explosions on one Indonesian reef across 483 days

Researchers placed hydrophones at multiple reef sites and trained algorithms to distinguish blast signatures from other underwater sounds. The 483-day deployment captured 3,548 events with clear spatiotemporal clustering near known fishing grounds, far exceeding visual patrol estimates. This passive method eliminates observer bias and operates continuously regardless of weather or darkness. Blast fishing collapses reef structure and removes both target and non-target species, accelerating biodiversity loss on reefs already stressed by thermal bleaching. Economic analyses show short-term income spikes for fishers mask multi-year declines in catch per unit effort and tourism revenue. Indonesian enforcement data remain sparse; the acoustic record supplies the first high-resolution baseline that can be paired with patrol logs or satellite imagery. Community livelihood programs paired with targeted enforcement have reduced blasts elsewhere in Southeast Asia when sustained beyond two years. Scaling similar acoustic networks across priority reefs would allow managers to test whether fines or gear-substitution incentives cross the threshold needed for measurable recovery within five years.