Marine OECMs (Other Effective Area-Based Conservation Measures) refer to marine areas outside formal marine protected areas that nevertheless achieve long-term biodiversity conservation through effective governance and management measures. The concept originates from the international “30×30” biodiversity target under the Kunming–Montreal Global Biodiversity Framework, which calls for conserving at least 30% of terrestrial and marine areas by 2030.

Under Article 6 of the Marine Conservation Act, the central competent authority may recognize Marine OECMs and establish relevant recognition standards. Unlike traditional marine protected areas, this framework recognizes that areas managed by local communities, indigenous peoples, industries, civil society organizations, or government agencies may still contribute significantly to marine conservation even without formal protected-area designation.

Marine OECMs must possess clearly defined geographic boundaries, management mechanisms, and demonstrable long-term conservation outcomes. Recognition criteria include habitats for endangered species, areas with high biodiversity, ecologically connected regions, blue carbon ecosystems, climate refugia, and other ecologically important marine environments.

The system further distinguishes between “Marine OECMs” and “Potential Marine OECMs.” Related regulations establish procedures for application, review, on-site inspection, information disclosure, effectiveness evaluation, amendment, and revocation. Through this framework, Taiwan aims to expand its marine conservation network, strengthen ecological connectivity and climate resilience, and encourage collaborative marine governance involving government agencies, indigenous peoples, local communities, and civil society.