Measuring the direct regional economic activity generated by marine interventions: Evidence from crown‑of‑thorns starfish control on the Great Barrier Reef

Marine interventions are expanding worldwide to address climate and other stressors on marine ecosystems. As these programs expand, their evaluation is no longer limited to ecological outcomes but also includes socio-economic contributions. These can be assessed by valuing ecosystem services or by quantifying the direct regional economic activity generated by program delivery. Complementing ecosystem service valuation studies, we adopt the latter and assess the direct regional activity generated by the Crown‑of‑Thorns Starfish (COTS) Control Program in Tropical North Queensland, Australia. Using a hybrid input-output modelling framework that incorporates household effects and detailed expenditure data from Cairns-based operations, we quantify the direct and flow-on economic impacts of the program. Our analysis shows that an investment of AU$5.5 million in COTS operations during the 2023–2024 financial year generated approximately AU$20 million in total economic output and supported 61 full-time equivalent jobs, corresponding to type II output and employment multipliers of 1.9 and 1.8. The economic benefits are concentrated in professional, scientific and technical services, administrative and support services, and rental and hiring services, with smaller contributions in ships and boat manufacturing and retail trade. Beyond the ecological imperative of protecting the Great Barrier Reef, these findings highlight the tangible economic value of large-scale marine management programs for regional economies. Our case study provides a replicable approach for assessing local economic impacts of conservation programs and offers policy-relevant evidence to support continued and strategically targeted investment in reef management.