Stochastic projections for the toothfish (Dissostichus eleginoides) resource in the Prince Edward Islands vicinity
For stochastic future recruitment and for annual catch levels of 0, 200, 400, 575 and 675 tonnes, the median of the spawning biomass estimates for the New Base case model drops initially, but returns to its current level within a decade. However, for variants of this model that attempt to improve th...
| Main Authors: | , |
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| Format: | Report |
| Language: | English |
| Published: |
Faculty of Science
2018
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| Subjects: | |
| Online Access: | http://hdl.handle.net/11427/30231 https://open.uct.ac.za/bitstream/11427/30231/1/FISHERIES_2018_OCT_SWG-DEM_66%20Toothfish%20stochastic%20projections.pdf |
| Summary: | For stochastic future recruitment and for annual catch levels of 0, 200, 400, 575 and 675 tonnes, the median of the spawning biomass estimates for the New Base case model drops initially, but returns to its current level within a decade. However, for variants of this model that attempt to improve the fit to the trotline CPUE or which adjust the projected recruitments to reflect a possible regime shift, only annual catches in the range of 200 to 400 tonnes maintain the spawning biomass above the current level at the end of a 20 year period. This suggests that consideration should perhaps be given to recommending some decrease in the present annual TAC of 575 tonnes. |
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