Improving the definition of fishing effort for important European fleets by accounting for the skipper effect
|Author(s)||Marchal Paul1, Andersen B2, Bromley D3, Iriondo A4, Mahevas Stephanie5, Quirijns F6, Rackham B3, Santurtun M4, Tien N6, Ulrich C2|
|Affiliation(s)||1 : IFREMER, F-62321 Boulogne, France.
2 : DIFRES, DK-2900 Charlottenlund, Denmark.
3 : CEFAS, Lowestoft NR33 0HT, Suffolk, England.
4 : Txatxarramendi Ugarte ZG, Inst Tecnol Pesquero & Alimentario AZTI, Fisheries Resources Dept, Sukarrieta 48395, Spain.
5 : IFREMER, F-44311 Nantes 03, France.
6 : Netherlands Inst Fishery Res, Dept Biol & Ecol, NL-1970 AB Ijmuiden, Netherlands.
|Source||Canadian journal of fisheries and aquatic sciences (0706-652X) (NRC), 2006-03 , Vol. 63 , N. 3 , P. 510-533|
|WOS© Times Cited||47|
|Keyword(s)||Fishing effort, Fishing mortality, Catch rates, GLM modeling, Skipper effect|
|Abstract||The scope of this paper is to quantify, for a wide selection of European fisheries, fishing tactics and strategies and to evaluate the benefits of adjusting the definition of. fishing effort using these elements. Fishing tactics and strategies were identified by metiers choices and a series of indices. These indices have been derived to reflect shifts in tactics (within a fishing trip) and in strategies (within a year). The Shannon-Wiener spatial diversity indices of fishing tactics (FT_SW) and strategies (YE_SW) had the greatest impact on catch rates. In particular, FT_SW was always negatively correlated to catch rates. One may anticipate that during a fishing trip, vessels with high FT_SW have been searching fish aggregations for a long time, while vessels with low FT_SW have been more efficient in finding these aggregations. The linkage between YE_SW and catch rates was of a more complex nature. Adjusting fishing effort by means of (i) the metier effect and (ii) the indices of tactics and strategies generally led to a substantial gain in the precision of the relationship between fishing mortality and fishing effort.|