Acronym PREMECS-II
Category
Fisheries
Title Development of predictive model of cod-end selectivity Programme FP6
Instrument (FP6)
Contact Type (FP7)
Strand (Interreg)
NA
Theme (FP7)
Activity Area (FP6)
Regional Area (Interreg)
Action (COST)
NA
Specific Programme (FP7)
NA
Funding source European Coordinator Priour Daniel Coordinator email Daniel.Priour@ifremer.fr
Coordinator institution
IFREMER - French Research Institute for Exploitation of the Sea (France)
Institutions involved
DIFRES - Danish Institute for Fisheries Research (Denmark) ,
ISEN WEST - ISEN Brest (France) ,
CNR-ISMAR - National Research Council; Institute of Marine Sciences (Italy) ,
NA - Scottish Ministry acting throug Fisheries Research Services (United Kingdom) ,
Start year 2002 End year 2005 Funding (€) € 2,151,628 Website NA Summary This proposal develops further a predictive model of cod-end selection so that the selectivity of commercially used cod-ends fished in commercial conditions can be predicted. The influence of (i) netting materials made from thicker and stiffer twines, (ii) the dynamic effects of the interaction of sea state, fishing vessel, trawl gear and cod-end and (iii) fish morphology and fish escape behaviour are investigated and included in the model. An individual Based Model of cod-end selection is also developed. This model is more complex and makes better use of the behavioural information that is available. Objectives The overall objective of this project is to further developed a predictive selectivity model, so that it can predict the selectivity of commercially used cod-ends fished in commercial conditions. Briefly, the influence of (i) netting materials made from thicker and stiffer twines, (ii) the dynamic effects of the interaction of sea state-fishing vessel-trawl gear-codend and (iii) fish morphology and fish escape behaviour will be investigated and included in the model. Description of the work - The twine bending stiffness and mesh structure of netting panels used at present by the fishing industry in the North Sea and the Mediterranean Sea will be determined. - The hydrodynamics around the cod-end will be modelled and the models tested with the results of flume tank trials. - A model of how the catch builds up at the back of the cod-end will be developed. - A dynamic trawl model will be further developed to take account of the dynamics of the vessel and the trawl doors. A dynamic cod-end model will be developed. The interaction of these models will be examined. - Sea trials will take place in the North Sea and the Mediterranean Sea to observe and quantify fish escape in the cod-end, to measure the morphology of some commercially important species and, in the Mediterranean Sea, to carry out some selectivity experiments. - All the above information will be included in the selectivity models, the predictions of which will be compared with a broad range of historic selectivity data sets. Milestones - Methodology for the measurement of mesh opening stiffness and twine elasticity of netting used on commercial fleet. - Models of catch in the cod-end, of the dynamic of the trawl and of the dynamic of the cod-end. - Measurement of selectivity, fish geometry and fish behaviour in the cod-end during sea trials. - Models of selectivity process in cod-end and comparison with results of sea trials.
The overall objective of this project is to further develop a predictive selectivity model, so that it can predict the selectivity of commercially used cod-ends fished in commercial conditions. Briefly, the influence of: (1) Netting materials made from thicker and stiffer twines; (2) The dynamic effects of the interaction of sea state-fishing vessel-trawl gear-codend; (3) Fish morphology and fish escape behaviour will be investigated and included in the model.
Keywords
Gear selectivity;
Fishing technology;
Marine Region
6
Central North Sea (27.IVb)
13
Northern North Sea (27.IVa)
5
Southern North Sea (27.IVc)
3
Marine Region Map
