Evolution of operational management procedures for the South African West Coast rock lobster (Jasus lalandii) fishery

摘要

The commercial fishery for Jasus lalandii, the South Africa West Coast rock lobster, began in the late 1800s and at its peak in the early 1950s yielded an annual catch of 18 000 t. Although this annual catch has dropped to only some 2000 t over recent years, the fishery remains South Africa's third most valuable for landed value. The primary reason for the low total allowable catch (TAC) over these recent years has been a marked drop in somatic growth rate that occurred at the end of the 1980s, for reasons that remain unexplained. A key problem in formulating TAC recommendations with longer-term objectives in mind, has been uncertainties about likely future trends, particularly in somatic growth and recruitment. To address this problem, an "operational management procedure" (OMP) was adopted in 1997 and has twice been re-evaluated and modified (in 2000 and 2003) in the light of further data and changing perceptions of resource dynamics. The history of this process is reviewed, concentrating on the most recent modification. In particular, a summary is given of the process by which the merits of alternative management procedures were evaluated over a range of important uncertainties about the dynamics of the resource. This summary includes a discussion of the key trade-offs between resource rebuilding, future TAC trends and TAC variability, and the eventual choice that was made.The paper concludes by listing a number of lessons learnt concerning best practice for OMP development as this process evolved.