A Stock Production Model Incorporating Covariates (ASPIC) for Greenland halibut (Reinhardtius hippoglossoides)
A stock production model (ASPIC) was applied to age-aggregated biomass indices covering the same time period and from surveys used in the XSA assessment accepted by Scientific Council in recent years. Results were sensitive to the starting estimates for several parameters, and resulted in two very d...
| Main Authors: | , |
|---|---|
| Other Authors: | |
| Format: | Text |
| Language: | English |
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.615.9487 http://archive.nafo.int/open/sc/2009/scr09-048.pdf |
| Summary: | A stock production model (ASPIC) was applied to age-aggregated biomass indices covering the same time period and from surveys used in the XSA assessment accepted by Scientific Council in recent years. Results were sensitive to the starting estimates for several parameters, and resulted in two very different estimates of relative biomass and fishing mortality. Retrospective patterns were also problematic for the two resulting solutions. When standardized CPUE series (from Canadian, Russian and Portuguese fisheries) were included in the model with the catch and survey indices, model diagnostics and fit were poor and results were considered unacceptable. Using only the CPUE series and catch information resulted in model fits and results similar to those using biomass indices and catch alone. Sensitivity analyses for the model including only CPUE and catch also indicated two possible solutions. Retrospective patterns for the CPUE/catch runs were severe and were not considered acceptable. |
|---|