This thesis is based on Gordon-Schaefer model, and assesses Argentine shortfin squid¡¦s stock by using the data of Southwest Atlantic from FAO between 1983 and 2009. First, estimate the equilibrium level of the open-access fishery and dynamic optimization fishery and compare to each other. Then estimate annual Argentine shortfin squid¡¦s stock size, comparing the stock size with the equilibrium level of the two fishery models. The result is that Argentine shortfin squid¡¦s stock size has no crisis of extinction now in Southwest Atlantic. In addition, simulate Argentine shortfin squid¡¦s stock size under management and no management status in the future. The result is that it will make the Argentine shortfin squid sustainable development under dynamic optimization fishery, and this fishery model will be a good management. Finally, this thesis based on the catch of Southwest Atlantic Argentine shortfin squid, which we figure out the fluctuation of catch by literatures, and do the sensitivity analysis.

This research is based on Gordon-Schaefer model, using the statistic data from the FAO between 1983 to 2007 to conduct an assessment on Argentine shortfin squid, Illex argentinus. First of all, calculate and compare the equilibrium levels of open access fishery and present value maximization fishery, then evaluate the stock size of Illex argentinus and compare the equilibrium levels of two models with the statistic readings, the result shows that Illex argentinus has no sign of depletion, but it has not yet reached the best status for development. By using sensitivity analysis,we understand the changes on the effort and stock effected by varying different parameters. Finally, by simulating the stock size of open access fishery and present value maximization fishery, we find that unrestricted developing can end up the resources, but Illex argentinus will receive sustainable development, if it can be effectively managed.