FINAL REPORT An empirical relationship between changes in headrope - - PDF document

• An empirical relationship between changes in

headrope length and catch for the NPF fleet

A report to AFMA for the NPF RAG Bill Venables and Matthew Browne CMIS Report Number 07/80 29 June 2007 Commercial-in-confidence

• FINAL REPORT

• FINAL REPORT

Enquiries should be addressed to: Matthew Browne CSIRO Mathematical & Information Sciences PO Box 120 Cleveland QLD 4163 Tel.: +61 7 3826 7267 Matthew.Browne@CSIRO.au

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• Scope .................................................................................................................................................. 3

Study seasons: 1987-2006.................................................................................................................. 4 Catch and effort................................................................................................................................... 4 Vessel characteristics.......................................................................................................................... 5

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A graphical representation of the main relationship............................................................................ 9

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Stability over time .............................................................................................................................. 12 Sources of information and confounding........................................................................................... 13 Scale of the analysis ......................................................................................................................... 14 Implied link between headrope and effort changes........................................................................... 14

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Data ................................................................................................................................................... 17 Statistical model ................................................................................................................................ 18 Results............................................................................................................................................... 19 A graphical representation of the main relationship.......................................................................... 20

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• Appendix 1: The tiger prawn stock regions for the NPF
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• Appendix 2: An extract from the Effort Trade-offs report

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