Objective:To investigate the length distribution,sex ratio,length-weight relationship,age and growth of Rostroraja alba in the Gulf of Gabes.Methods:This study estimated age and growth of the white skate,Rostroraja al...Objective:To investigate the length distribution,sex ratio,length-weight relationship,age and growth of Rostroraja alba in the Gulf of Gabes.Methods:This study estimated age and growth of the white skate,Rostroraja alba by counting vertebral band pairs from 112 specimens taken by commercial fisheries during 2006-2009 from the Gulf of Gabes(Southern Tunisia,Central Mediterranean Sea).Results:This is the first and only known information in regards to the age and growth of this species in Tunisia.Vertebra diameter was strongly correlated with total length and age,which were expressed by linear or cubic regression equations.The oldest female in this study was 35 years and 160 cm,whereas the oldest male was 32 years and 150 cm.The von Bertalanffy growth parameters were TL_(∞)=(202.26±3.40)cm,K=(0.040±0.038)/year and t_(0)=(1.84±0.01)10^(-1)/year for females and TL_(∞)=(198.60±3.61)cm,K=(0.060±0.076)/year and t_(0)=(1.28±0.04)/year for males.Conclusions:This study would be an effective tool for fishery biologists,managers and conservationists to initiate management strategies and regulations for the sustainable conservation of the remaining stocks of this species in the Gulf of Gabes(Southern Tunisia)ecosystem.展开更多
基金Supported by the National Institute of Science and Technology of the Sea of Sfax(Tunisia).
文摘Objective:To investigate the length distribution,sex ratio,length-weight relationship,age and growth of Rostroraja alba in the Gulf of Gabes.Methods:This study estimated age and growth of the white skate,Rostroraja alba by counting vertebral band pairs from 112 specimens taken by commercial fisheries during 2006-2009 from the Gulf of Gabes(Southern Tunisia,Central Mediterranean Sea).Results:This is the first and only known information in regards to the age and growth of this species in Tunisia.Vertebra diameter was strongly correlated with total length and age,which were expressed by linear or cubic regression equations.The oldest female in this study was 35 years and 160 cm,whereas the oldest male was 32 years and 150 cm.The von Bertalanffy growth parameters were TL_(∞)=(202.26±3.40)cm,K=(0.040±0.038)/year and t_(0)=(1.84±0.01)10^(-1)/year for females and TL_(∞)=(198.60±3.61)cm,K=(0.060±0.076)/year and t_(0)=(1.28±0.04)/year for males.Conclusions:This study would be an effective tool for fishery biologists,managers and conservationists to initiate management strategies and regulations for the sustainable conservation of the remaining stocks of this species in the Gulf of Gabes(Southern Tunisia)ecosystem.
