Modelling cannibalism and inter-species predation for Cape hake Merluccius capensis and M. paradoxus: Model specifi?cations and preliminary results

In summary, this work aims to build on that done by Punt and Leslie (1995) and Punt and Butterworth (1995) in the development of a multispecies model for the two Cape hake species, Merluccius capensis and M. paradoxus. There, the authors aimed to construct a model which included hake, seals and other predatory fish and then to use this model to assess the consequences of different levels of consumption of hake by seals on the hake fishery in the context of the change in the size of sustainable hake TACs and catch rates. They also aimed to investigate the effect of seal culling on the fishery. In the years that have passed since, more data have become available, and the hake assessment models have been continuously developed. The aim of the hake cannibalism and inter-species predation model presented in this document is to update the work done by Punt and Leslie (1995) with new data, and to extend the model to the level of the current hake assessment model.