Design and evaluation of offshore marine protected areas

Marine protected areas (MPAs) is an area defined by legally the government or local communities such as fisheries organizations, less impacted by human activities such as land use or fisheries in comparison to neighboring areas. Some small MPAs are effective to improve fisheries resources of sessile organisms like sea-urchin that is used surrounding the MPAs. Trawl nets or purse seine nets in a wide area are regulated in some offshore MPAs. In contrast, mobile MPAs that areas are not spatially fixed may be effective for migratory species like tunas. Recently a purse seine net fishery exploits Pacific bluefin tunas during the spawning season. Fisheries and spawning grounds often shift from year to year. Satellite data are probably useful to detect spawning ground for each year. I will discuss possibility of spatial design of MPAs to protect spawning ground of Pacific bluefin tunas and evaluate effects of such MPAs in the tuna stocks and fisheries.