In this research, using the statistic catch data of northwest pacific saury from the Overseas Fisheries Development Council of The Republic of China between 2004 to 2007 to conduct an resource assessment on pacific saury. First of all, calculate and compare the equilibrium level of open access fishery and the net present value maximization fishery. And then, using the northwest pacific saury statistic catch data from the Food and Agriculture Organization of The United Nations between 2005 to 2007 for the simulation analysis of resource of pacific saury, and the results simulated with the two fishing grounds of the equilibrium value for comparison. The results showed that the problem of depletion of the resource does not exist. The final, assumption that the value of parameters are changing in the range of reasonable in order to understand the impact of the changing in the fishery resource of the stock and effort. Collate and analyze the results, and expect that the results can be a management reference for the management of the northwest pacific saury fisheries.

Abstract Because the number of sharks is decreasing , the problem has been concerned in recent years. In this paper , I conduct a research about the shark bycatch problem¡Ataking the target specie of bigeye tunas and the bycatch specie of sharks as the research objects . Initially I collect from 2000 to 2007 Atlantic bigeye tuna and shark catches datas for resource assessment.and then making comparasion with resource equilibrium values of open access fishery model and net present value maximization fishery model. it is found during the period it has showed a upward trend for bigeye tuna resources¡Abut it has not showed the bigeye tuna resources achive the optimal level. It has showed a diminishing trend for shark resources, the result shows the resources will face extinction crisis if the fishery is not controlled well. Then, doing sensitivity analysis to understand the effects of exogenous parameters to bigeye tuna and shark catches, resources and efforts. Finally, facing with the sharks bycatch problem , discussing the effect of improved fishing gears on sharks bycatch control by doing the sensitivity analysis of fishing hook cost and bycatch coefficient to shark resources and catches¡OFrom the results , it shows that no matter affecting the fishing hook cost or bycatch coefficient , the amount of shark can be reduced effectively by adopting improved fishing gears.