KPFM2, be careful what you ask for – you just might get it

We have substantially revised the krill-predator-fishery model that was presented to the WG-EMM in 2005. The new version of our model is called KPFM2, and we have addressed all four of the changes which the WG-EMM indicated would be required to use the model for providing advice on the allocation of catch among the SSMUs (i.e., add seasonality, consider alternative movement hypotheses, add thresholds in krill density that cause fishing to cease, and compute a performance measure that compares the distribution of simulated catch to the distribution of historical catch). We have added a substantial number of other features to the model as well. Many of these features were suggested to us at the 2005 meeting of the WG-EMM but not recorded as requirements; we have made a serious attempt to address most suggestions. These additional, features include
• predators that can forage outside their natal SSMUs;
• predators whose survival is a function of their foraging performance;
• differential competitive strengths among predators and the fishery;
• control over the seasonal timing of fishing and predator breeding that allows fishing and breeding to overlap or be disjunct;
• a facility for conducting simplified management strategy evaluations; and
• general improvements to the flexibility, performance, and usability of the model.
In our opinion, KPFM2 can be a useful tool for evaluating the outcomes of the six management procedures that are candidates for allocating the precautionary krill catch among SSMUs.