Length-weight relationships （LWRs） were determined for fish species Diplodus vulgaris from the Benghazi coast along the eastern Mediterranean Sea coast of Libya. Samples were collected using trammel nets. The parame...Length-weight relationships （LWRs） were determined for fish species Diplodus vulgaris from the Benghazi coast along the eastern Mediterranean Sea coast of Libya. Samples were collected using trammel nets. The parameters a and b from the LWR formula W = aLb were estimated. The values of the exponent b of the length-weight relationships in all categories range between 2.295 in September to 3.208 in August. The total number of fish samples investigated were 290, from which 179 were males, 41 females and 70 fishes immature. The sex ratio male to female were 4.3：1. In January, August and Females the slope ＂b＂ close to equal 3, were the categories exhibited isometric relationship, in September, October and November were slope ＂b＂ not equal 3, which the categories exhibited negative allometric relationship. The mean observed length of male was 18.29 cm at mean observed weight 114.8 g, and mean observed length of female was 19.15 cm at mean observed weight 133.97 g.The general equation for the length-weight relationship for both sex was： W = 0.03835L277, for male was： W = 0.036 L274, for female, W = 0.016 L302.展开更多
The feeding habits of 140 specimens of Carcharhinus brachyurus （Fam. Carcharhinidae） inhabiting Ain-EI-Ghazala lagoon on the Mediterranean Sea, eastern Libya were studied monthly from February to June 2013. The annu...The feeding habits of 140 specimens of Carcharhinus brachyurus （Fam. Carcharhinidae） inhabiting Ain-EI-Ghazala lagoon on the Mediterranean Sea, eastern Libya were studied monthly from February to June 2013. The annual diet composition, monthly variations in the diet composition, the variations of diet with length and the intensity of feeding were studied. Carcharhinus brachyurus feed on a wide variety of prey types： Pelagic bony fishes （54.5%）, benthic bony fishes （36.4%）, Cephalopods （6.8%）, Cartilaginous fishes （1.7%） and Fish parts （0.6%）. The Pelagic bony fishes and benthic bony fishes were the major food items during the study period in question, and they were found in all length groups. According to the results that were gleamed from this study, when the size of the sharks increased, the proportion of pelagic bony fishes within the sharks＇ stomachs grew in size, while the benthic bony fishes and Cephalopods decreased in size. The feeding intensity was quite high during the winter, spring and summer, this study is the first to study the Elasmobranchs in Libya, and it will be good base to study another species, specifically.展开更多
文摘Length-weight relationships （LWRs） were determined for fish species Diplodus vulgaris from the Benghazi coast along the eastern Mediterranean Sea coast of Libya. Samples were collected using trammel nets. The parameters a and b from the LWR formula W = aLb were estimated. The values of the exponent b of the length-weight relationships in all categories range between 2.295 in September to 3.208 in August. The total number of fish samples investigated were 290, from which 179 were males, 41 females and 70 fishes immature. The sex ratio male to female were 4.3：1. In January, August and Females the slope ＂b＂ close to equal 3, were the categories exhibited isometric relationship, in September, October and November were slope ＂b＂ not equal 3, which the categories exhibited negative allometric relationship. The mean observed length of male was 18.29 cm at mean observed weight 114.8 g, and mean observed length of female was 19.15 cm at mean observed weight 133.97 g.The general equation for the length-weight relationship for both sex was： W = 0.03835L277, for male was： W = 0.036 L274, for female, W = 0.016 L302.
文摘The feeding habits of 140 specimens of Carcharhinus brachyurus （Fam. Carcharhinidae） inhabiting Ain-EI-Ghazala lagoon on the Mediterranean Sea, eastern Libya were studied monthly from February to June 2013. The annual diet composition, monthly variations in the diet composition, the variations of diet with length and the intensity of feeding were studied. Carcharhinus brachyurus feed on a wide variety of prey types： Pelagic bony fishes （54.5%）, benthic bony fishes （36.4%）, Cephalopods （6.8%）, Cartilaginous fishes （1.7%） and Fish parts （0.6%）. The Pelagic bony fishes and benthic bony fishes were the major food items during the study period in question, and they were found in all length groups. According to the results that were gleamed from this study, when the size of the sharks increased, the proportion of pelagic bony fishes within the sharks＇ stomachs grew in size, while the benthic bony fishes and Cephalopods decreased in size. The feeding intensity was quite high during the winter, spring and summer, this study is the first to study the Elasmobranchs in Libya, and it will be good base to study another species, specifically.
