FISHERIES_2016_MAR_SWG_WCRL_03.pdf (1.37 MB)
The impact on assessments of and projections for the West Coast Rock lobster resource if poaching levels are substantially larger than assumed for the present Reference Case assessment
reportposted on 2022-02-28, 04:39 authored by Susan HollowaySusan Holloway, Doug ButterworthDoug Butterworth
The current Reference Case assessment of the West Coast rock lobster resource is repeated for the scenarios for which recent levels of poaching are five (x5) and ten (x10) times larger than those presently assumed, and forward projections for these scenarios are conducted under the assumptions that both the current legal and illegal components of the catch remain unchanged. Absolute values of the present male biomass above 75 mm carapace length are not appreciably changed for these scenarios, essentially because the associated recent larger recruitments which they suggest are largely offset by the removals of lobster of sub-legal size by the poachers. It is evident from the projections that although the resource is sustained under the RC and the x5 poaching scenario, it shows a steady downward trend in the biomass of male lobsters of legal size under the x10 poaching scenario. This increases the importance of obtaining an improved estimate of the present level of poaching.
Department/UnitDepartment of Mathematics and Applied Mathematics, University of Cape Town