Second report of mesh selection studies conducted in the People's Democratic Republic of Yemen on the cuttlefish Sepia pharaonis
| dc.coverage | Yemen | |
| dc.creator | Sanders, M.J.;Bouhlel, M.B. | |
| dc.date | 2023-04-27T12:11:09Z | |
| dc.date | 2023-04-27T12:11:09Z | |
| dc.date | 1982 | |
| dc.date | 2018-01-10T07:24:51.0000000Z | |
| dc.date.accessioned | 2026-06-27T20:13:00Z | |
| dc.description | This paper describes a repeat of an earlier study by the authors, concerning the mesh selection properties of trawl cod-ends of various mesh sizes on the cuttlefish Sepia pharaonic. A brief resume of the findings is as follows: the estimated 50% selection lengths with 95% confidence limits for single braided polyethylene cod-ends of 12.4 cm, 13.6 cm and 16.8 cm mesh sizes were 17.87+0.28 cm, 20.74+- 0.53 cm and 26.95+-1.07 cm; the 50% selection lengths and selection ranges were very similar to t hose obtained in the earlier study in respect to the 12.4 cm cod-end, but higher in respect to the 13.6 cm cod-end; the 16.8 cm cod-end had not been previously used; the previously held assumption that the 50% selection lengths and cod-end mesh sizes were proportionally related was seen as inappropriate, and hence also the estimation of selection factors; the more appropriate relationship was seen to be one of non-proportional linearity, and the regression equation considered most compatible wit h the observations as 50% selection length (cm)=2.03 mesh size(cm) -7.41; for a chosen value of the 50% selection length, this equation gives substantially different values for the choice of appropriate cod-end mesh size, than the selection factors estimated from the earlier study. | |
| dc.format | 29 | |
| dc.format | application/pdf | |
| dc.identifier | https://openknowledge.fao.org/handle/20.500.14283/bt930e | |
| dc.identifier | http://www.fao.org/3/a-bt930e.pdf | |
| dc.identifier.uri | http://hdl.handle.net/123456789/187797 | |
| dc.language | English | |
| dc.publisher | FAO ; | |
| dc.rights | FAO | |
| dc.title | Second report of mesh selection studies conducted in the People's Democratic Republic of Yemen on the cuttlefish Sepia pharaonis | |
| dc.title | Second report of mesh selection studies conducted in the People's Democratic Republic of Yemen on the cuttlefish Sepia pharaonis | |
| dc.type | Document |