Comparison of age- and length-based harvest control rules for the South Georgia icefish (Champsocephalus gunnari) fishery

An age-based operating model was constructed and used to derive an initial numbers at age vector for the population. An age-based harvest control rule was then applied using the operating model dynamics and assuming perfect knowledge of the resource (initial numbers at age, maturity and weight at age). The initial numbers at age was also converted to numbers at length, which was used to initialise the length based harvest control rule, again assuming perfect knowledge of the resource. Total allowable catches (TACs) and harvest rates (H) from the length and age based methods could then be compared to test the performance of the length based method, with results suggesting that the two approaches determine similar harvest strategies.