Marine ecological footprint indicates unsustainability of the Pohnpei (Micronesia) coral reef fishery

摘要

Throughout the tropics, developing countries and territories are highly dependent on nearshore marine resources for food and income, however information on the sustainability and proper management of these fisheries is lacking. In Pohnpei, Micronesia, the sustainability of a coral reef finfishery was assessed by comparing coral reef fish demand to coral reef biocapa-city using a marine ecological footprint (MEF) analysis. Based on geo-referenced satellite and aerial imagery, Pohnpei and surrounding atolls have 184.2 km~2 of coral reef habitat with a sustainable finfish yield of 573-1118 t yr~(-1), however total harvest was estimated at 4068 t yr~(-1), exceeding biocapacity by 360-710%. The MEF was supported by observed impacts to coral reef resources, including (1) long-term declines in fish spawning aggregation density, (2) reductions in mean size, age and fecundity of key commercial species, (3) reliance on undersized fish, and (4) decadal declines in mean size and abundance of fishes of iconic value and critical to ecosystem maintenance. The commercial fishery was responsible for 68% of finfish catch volume, while reef fish consumption, at 93 kg person~(-1) yr~(-1), was among the highest in the region. To sustainably meet current demand, up to 833 km~2 of additional reef area would be required. The study illustrates the MEF, at least rudimentarily, reflects biological reality on local reefs and represents a valuable analytical tool in a marine policymaker's toolbox.