Namibian orange roughy age-structured production model assessments and projections for 2006
| dc.contributor.author | Brandão, Anabela | |
| dc.contributor.author | Butterworth, Doug S | |
| dc.date.accessioned | 2016-03-22T09:12:59Z | |
| dc.date.available | 2016-03-22T09:12:59Z | |
| dc.date.issued | 2006 | |
| dc.date.updated | 2016-03-22T09:08:15Z | |
| dc.description.abstract | Updated assessments of the four orange roughy aggregations off Namibia, based upon a maximum penalised likelihood approach which uses all available indices of abundance and reflects the proportion of a stock present at the fishing aggregation each year, are presented, and projections under constant catch levels reported. Results suggest that Frankies and Rix are presently at some 60% of their pre-exploitation level, but that Hotspot is perhaps much more depleted at about 10%. Estimates for Johnies range between these extremes, depending on the relative weight accorded survey and CPUE indices of abundance. Overall, medium term sustainable yields would seem to be in the vicinity of 1750 to 2 500 tons. Broadly speaking, MSY estimates are some 5– 30% less than estimated a year previously. However, varying proportions of abundance present at aggregations from year to year would lead to difficulties in making a catch of this size every year. | en_ZA |
| dc.identifier.apacitation | Brandão, A., & Butterworth, D. S. (2006). <i>Namibian orange roughy age-structured production model assessments and projections for 2006</i> University of Cape Town ,Faculty of Science ,Marine Resource Assessment and Management Group. Retrieved from http://hdl.handle.net/11427/18146 | en_ZA |
| dc.identifier.chicagocitation | Brandão, Anabela, and Doug S Butterworth <i>Namibian orange roughy age-structured production model assessments and projections for 2006.</i> University of Cape Town ,Faculty of Science ,Marine Resource Assessment and Management Group, 2006. http://hdl.handle.net/11427/18146 | en_ZA |
| dc.identifier.citation | Brandão, A., & Butterworth, D. S. (2006). Namibian orange roughy age-structured production model assessments and projections for 2006. Namibian Ministry of Fisheries and Marine Resources document: DWFWG/WkShop/Feb06/Doc, 3. | en_ZA |
| dc.identifier.ris | TY - Working Paper AU - Brandão, Anabela AU - Butterworth, Doug S AB - Updated assessments of the four orange roughy aggregations off Namibia, based upon a maximum penalised likelihood approach which uses all available indices of abundance and reflects the proportion of a stock present at the fishing aggregation each year, are presented, and projections under constant catch levels reported. Results suggest that Frankies and Rix are presently at some 60% of their pre-exploitation level, but that Hotspot is perhaps much more depleted at about 10%. Estimates for Johnies range between these extremes, depending on the relative weight accorded survey and CPUE indices of abundance. Overall, medium term sustainable yields would seem to be in the vicinity of 1750 to 2 500 tons. Broadly speaking, MSY estimates are some 5– 30% less than estimated a year previously. However, varying proportions of abundance present at aggregations from year to year would lead to difficulties in making a catch of this size every year. DA - 2006 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2006 T1 - Namibian orange roughy age-structured production model assessments and projections for 2006 TI - Namibian orange roughy age-structured production model assessments and projections for 2006 UR - http://hdl.handle.net/11427/18146 ER - | en_ZA |
| dc.identifier.uri | http://hdl.handle.net/11427/18146 | |
| dc.identifier.vancouvercitation | Brandão A, Butterworth DS. Namibian orange roughy age-structured production model assessments and projections for 2006. 2006 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/18146 | en_ZA |
| dc.language | eng | en_ZA |
| dc.publisher.department | Marine Resource Assessment and Management Group | en_ZA |
| dc.publisher.faculty | Faculty of Science | en_ZA |
| dc.publisher.institution | University of Cape Town | |
| dc.title | Namibian orange roughy age-structured production model assessments and projections for 2006 | en_ZA |
| dc.type | Working Paper | en_ZA |
| uct.type.filetype | Text | |
| uct.type.filetype | Image | |
| uct.type.publication | Research | en_ZA |
| uct.type.resource | Research paper | en_ZA |