Development of a stock-recruit model for simulating stock dynamics for uncertain situations: the example of northeast atlantic mackerel (scomber scombrus)

• Main Authors: Simmonds, E. J., Campbell, A., Skagen, D., Roel, B. A., Kelly, C.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Oxford University Press (OUP) 2011
• Subjects: fisheries management; model probability; stock-recruit relationship; population-dynamics; fish recruitment; climate-change; regime shifts; management; ecosystem; fisheries; sea; strategy; proposal; Northeast Atlantic
• Online Access: http://hdl.handle.net/10379/13916; https://doi.org/10.13025/28049; https://doi.org/10.1093/icesjms/fsr014

The assumption of a relationship between recruitment and a spawning stock is the cornerstone of the precautionary approach and may constrain the use of a maximum sustainable yield (MSY) target for fisheries management, because the failure to include such a relationship suggests that providing a measure of stock protection is unnecessary. The implications of fitting different functional forms and stochastic distributions to stock-and-recruit data are investigated. The importance of these considerations is shown by taking a practical example from management: the management plan for Northeast Atlantic mackerel (Scomber scombrus), a fish stock with an average annual catch of 600 000 t. The historical range of spawning-stock biomass is narrow, and historical data from a stock assessment explain only a small proportion of the recruitment variability. We investigate how best to reflect the uncertainty in the stock-recruit relationship. Selecting a single model based on simple statistical criteria can have major consequences for advice and is problematic. Selecting a distribution of models with derived probabilities gives a more complete perception of uncertainty in dynamics. Differences in functional form, distribution of deviations, and variability of coefficients are allowed. The approach appropriately incorporates uncertainty in the stock-recruit relationship for F-MSY estimation.