The Gulf of Beibu, recognized as one of the traditional fishing grounds, is a center of rich biodiversity in
the northern South China Sea. Based on the Beibu Gulf ecosystem constructed by the Ecopath and Ecosim
model (in the late 1990s), we used Ecospace to evaluate the existing fishery management system and
assess the potential of marine protected areas (MPAs) in the Beibu Gulf over a short (5-year), medium
(10-year), and long-term (20-year) scenario. The results suggest that the current trawl closure and the
midsummer moratorium system used in the Gulf fishery management approach appear to offer minimal
benefits for stock recovery because of the high implementation and administrative costs; also, the biomass
of valuable groups would decrease drastically with simulation time, and the large predator groups, such
as the large demersal and pelagic fishes, would even be reduced to depletion in the long-term (20-year)
simulation.