At COP16 in Calí, Colombia, member states are currently discussing how the global nature agreement adopted in Montreal in 2022 can be implemented. The goals include protecting 30% of the world’s land and sea areas by 2030. In a new study an international team of researchers led by the Leibniz Centre for Tropical Marine Research (ZMT) uses the example of Indonesia to provide critical insights into how alternative forms of conservation – so-called “other effective area-based conservation measures” (OECMs) – can complement marine protected areas (MPAs) to meet this biodiversity target. The results of the study have recently been published in the journal Ocean & Coastal Management.