Statistical Catch-at-Length Assessment of S. mentella and S. fasciatus in Units 1+2

Assessments of the two redfish species in these Units is attempted simultaneously to take account of the fact that they are distinguished only in the survey results and not in the commercial catches. Fitting the declines in the survey indices in Unit 1 for the earlier years proves a particular problem, and leads to the question of whether bounds could be placed on survey catchabilities (q) to avoid what seem to be some unrealistically high estimates of q for S. fasciatus. Allowing for occasional large recruitments in these populations shows promise for improving the fits to those survey indices. However this needs further investigation to determine whether associated poor fits to the survey catch at-length data can be avoided, and whether estimation stability can be improved.