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Fixed closure (FC) is a standard fisheries management tool for protecting sensitive species or species requiring conservation. However, an FC might not effectively manage migratory species because of the large uncertainties of their migration. Adaptive real-time closure (ARTC) is a tool that updates closure areas according to the latest information. This study aimed to evaluate the effectiveness of ARTC to conserve sensitive species for data-limited fisheries by a series of simulations using migration models with hotspots. In the single species simulation, the conservation ratio for the sensitive species in FC varies widely at greater migration uncertainty. In ARTC, a longer duration of a hotspot resulted in a higher conservation ratio. When the mean duration of hotspots was medium or long, the conservation ratio for the sensitive species was more than 50 % in more than 99 % of the simulation trials. In multispecies fisheries, a clear trade-off was observed between the conservation ratio of sensitive species and other species. ARTC was more effective than whole closure when the proportion of sensitive species was high or without closure when the proportion was low. Conditions in which ARTC was most appropriate were described for hotspot duration, increased numbers of individuals in a hotspot, and the relative value of conservation, representing the ratio of the value of conserving sensitive species to one of catching other species.

Cognizant of the state of depletion and to some extent, collapse of the fishery resources particularly in coastal areas, concerned ASEAN Member States (AMSs) have increasingly placed focus on the under-utilized marine fishery resources in the offshore areas of their respective Exclusive Economic Zones (EEZs). Many AMSs are therefore making considerations to exploit these offshore fishery resources to reduce fishing pressure on their respective coastal resources and give the coastal fishery resources respite for recovery and rebuilding (Garcia et al., 2018). The same concern was addressed by the AMSs during the June 2011 ASEAN-SEAFDEC Conference on Sustainable Fisheries for Food Security Towards 2929 “Fish for the People 2020: Adaptation to a Changing Environment” that led to the adoption of the “Resolution and Plan of Action on Sustainable Fisheries for Food Security for the ASEAN Region Towards 2020,” which include among others, the advocacy to: “Investigate the potential of under-utilized fisheries resources and promote their exploitation in a precautionary manner based upon analysis of the best available scientific information.” Responding to such needs and requirements, the Southeast Asian Fisheries Development Center (SEAFDEC) through its Training Department (SEAFDEC/TD) has been working closely with the AMSs for the conduct of marine fishery resources surveys and studies on the marine environment of specific offshore areas, such as the Gulf of Thailand, Andaman Sea, and South China Sea, utilizing the SEAFDEC research vessels, the M.V. SEAFDEC and the M.V. SEAFDEC 2, that aim to collect information on the status of marine fishery resources and oceanographic conditions, as well as build the capacity of human resources in the aspects of fisheries and oceanographic surveys, on board navigation practices, and marine engineering. The most recent of such surveys facilitated by SEAFDEC/TD, was the two month “Collaborative Research Survey on Marine Fishery Resources an