Biological studies on the Milk Shark, rhizoprionodon acutus in the Gulf of Suez /
Amgad Mohamed Shaaban
Biological studies on the Milk Shark, rhizoprionodon acutus in the Gulf of Suez / دراسات بيولوجية على القرش الحليبى رايزوبرايونودون أكيوتاس بخليج السويس Amgad Mohamed Shaaban ; Supervised Mohamed asem Said Marie , Ahmed Imam Dakrory , Manal Mostafa Sabrah - Cairo : Amgad Mohamed Shaaban , 2019 - 137 P. : charts , maps , photoghraphs ; 25cm
Thesis (Ph.D.) - Cairo University - Faculty of Science - Department of Zoology
The milk shark, Rhizoprionodon acutus (Rüppell, 1837), is one of the most abundant shark species landed at Ataka fishing port at the Gulf of Suez. A total of 357 individuals (165 males and 192 females) were collected from the trawl and artisanal fisheries. Males ranged from 44.6 to 88.5 cm TL, while females ranged from 47.8 to 97.2 cm TL. The total sex ratio was estimated at 1:1.16 for males and females respectively. Lengths at 50% maturity were estimated to be 76.5 cm TL for males and 74 cm TL for females. The vitellogenesis and gestation occur concurrently and thus females seem to have a reproductive cycle of one year with no resting period. The mean embryo lengths in different months and the presence of neonates in virtually all months, however, indicated that parturition takes place throughout the year with a peak in summer. Length and weight at birth, depending on term embryos and neonates ranged from 39.5- 44.6 cm TL (mean 42.05±2.55). Ovarian fecundity ranged from one to nine (mean 5.56±0.33). Uterine fecundity ranged from one to six embryos (mean 3.22±0.24)
Gulf of Suez Reproductive biology Rhizoprionodon acutus
Biological studies on the Milk Shark, rhizoprionodon acutus in the Gulf of Suez / دراسات بيولوجية على القرش الحليبى رايزوبرايونودون أكيوتاس بخليج السويس Amgad Mohamed Shaaban ; Supervised Mohamed asem Said Marie , Ahmed Imam Dakrory , Manal Mostafa Sabrah - Cairo : Amgad Mohamed Shaaban , 2019 - 137 P. : charts , maps , photoghraphs ; 25cm
Thesis (Ph.D.) - Cairo University - Faculty of Science - Department of Zoology
The milk shark, Rhizoprionodon acutus (Rüppell, 1837), is one of the most abundant shark species landed at Ataka fishing port at the Gulf of Suez. A total of 357 individuals (165 males and 192 females) were collected from the trawl and artisanal fisheries. Males ranged from 44.6 to 88.5 cm TL, while females ranged from 47.8 to 97.2 cm TL. The total sex ratio was estimated at 1:1.16 for males and females respectively. Lengths at 50% maturity were estimated to be 76.5 cm TL for males and 74 cm TL for females. The vitellogenesis and gestation occur concurrently and thus females seem to have a reproductive cycle of one year with no resting period. The mean embryo lengths in different months and the presence of neonates in virtually all months, however, indicated that parturition takes place throughout the year with a peak in summer. Length and weight at birth, depending on term embryos and neonates ranged from 39.5- 44.6 cm TL (mean 42.05±2.55). Ovarian fecundity ranged from one to nine (mean 5.56±0.33). Uterine fecundity ranged from one to six embryos (mean 3.22±0.24)
Gulf of Suez Reproductive biology Rhizoprionodon acutus