Science Advisory Report 2008/026
Advice on the stock definition of redfish (Sebastes fasciatus and S. mentella) in Units 1 and 2
Summary
- In Unit 1 and 2, there are two commercially important species of redfish: Sebastes fasciatus and S. mentella.<
- Population data indicates that the two species do not have the same life history, particularly in terms of reproduction and recruitment mechanisms. It is therefore recommended that the two species should be assessed separately.<
- A review of the biological data (genetics, morphometrics and otolith chemical signature) suggests that Units 1 and 2 corresponds to a single biological population of each species. It is therefore recommended that Unit 1 and 2 be grouped as a single biological unit for each of the two species and assessed as such.<
- However, it appears that both species present a complex geographic structuring within biological units, as inferred from differences in abundance, the genetics (S. fasciatus only), otolith chemical signatures and corroborated by traditional fisheries knowledge. Seasonal migration patterns are evident. It is recommended that this structuring shall be explicitly taken into consideration in the assessment and in the development of conservation and management strategies.<
- The scientific data should be re-analyzed on the new basis of two species, with each species showing population substructure.<
- A zonal assessment meeting should be organized to review the scientific data and to define the status of each species in the area presently called Unit 1 and Unit 2.<
- These findings may have implications for adjacent management areas.
Accessibility Notice
This document is available in PDF format. If the document is not accessible to you, please contact the Secretariat to obtain another appropriate format, such as regular print, large print, Braille or audio version.
- Date modified: