Influence of fishers' behaviour on the catchability of surface tuna schools in the Venezuelan purse-seiner fishery in the Caribbean Sea

被引:26
作者
Gaertner, D
Pagavino, M
Marcano, J
机构
[1] ORSTOM, Inst Francais Rech Sci Dev Cooperat, Lab HEA, F-34032 Montpellier 1, France
[2] Global Chips, Cumana 6101, Sucre, Venezuela
[3] Fondo Nacl Invest Agropecuarias, FONAIAP, Cumana 6101, Sucre, Venezuela
关键词
D O I
10.1139/cjfas-56-3-394
中图分类号
S9 [水产、渔业];
学科分类号
0908 ;
摘要
The influence of Venezuelan skippers' behaviour on the catchability of surface tuna schools was modelled using logistic regressions. Data obtained from observers onboard purse seiners indicated that fishers' fine-scale decisions, such as chasing and setting a school, were influenced by (i) the skipper's skill, (ii) the fishing equipment used (e.g., whether a bird radar was used or not), (iii) the features of the tuna school, and (iv) some environmental factors. The connections among the decisions related to the fishing process and these variables were synthesized in a causal network approach. Results clearly showed that schools (i) composed by fishes under 2 kg and (ii) where biomass was lower than 5 metric tons were disregarded by fishers. Because fishers used these thresholds to decide when to set the net, modifications in their behaviour over the years may introduce serious biases in the analysis of any catch rate and abundance relationship. An average daily activity record of a purse seiner shows the proportion of time spent in searching and in setting activities and highlights the impact that the use of new fishing equipment may have on fishing power.
引用
收藏
页码:394 / 406
页数:13
相关论文
共 34 条
[1]  
Agresti A., 1990, CATEGORICAL DATA ANA
[2]  
ALLEN RL, 1984, INTERAMERICAN TROPIC, V18, P301
[3]  
ARIZ J, 1992, INT WORKSHOP FISHING
[4]  
BARD FX, 1986, ICCAT COLL VOL SCI P, V25, P11
[5]  
BUCKLAND ST, 1988, REP INT WHALING COMM, V38, P411
[6]  
BURNHAM KP, 1992, WILDLIFE 2001 : POPULATIONS, P16
[7]  
FERRARIS J, 1995, COLLOQ SEMI, P263
[8]  
FONTENEAU A, 1989, ICCAT COLL VOL SCI P, V30, P104
[9]  
Freon P., 1991, P135
[10]   Use of generalized linear models to investigate the fishing strategies of tuna purse seiners, in presence of floating objects in the western Atlantic Ocean. [J].
Gaertner, D ;
Pagavino, M ;
Marcano, J .
AQUATIC LIVING RESOURCES, 1996, 9 (04) :305-323