Fisheries and biology of spinner shark Carcharhinus brevipinna in Ras-Lanuf shores, Libya-spring and summer 2019
Other Title(s)
مصائد وبيولوجية كلب بحر بوريشة Carcharhinus brevipinna في ساحل راس لانوف ليبيا ربيع وصيف 2019
Joint Authors
Bu Zayd, Isam Mahmud Khamis
Birfad, Muhammad Ayyad
Source
مجلة جامعة مصراتة للعلوم الزراعية
Publisher
Misurata University Faculty of Agriculture
Publication Date
2021-12-31
Country of Publication
Libya
No. of Pages
22
Main Subjects
English Abstract
Between March and August 2019, about 52 specimens of Carcharhinus brevipinna were collected from Ras-lanuf shores, Libya.
In a size range (60.3-270.3 cm) and weights (1551.11-39510.22 gm), to study their biology: In length-weight relationship was isometric (B=2.5934); values of condition factors (Kf and Kc) plummeted by increasing size, from 0.42 and 0.28 in 77.6 cm size, to Kf = 0.17 in 145.8 cm and Kc = 0.13 in 178.6 cm.
The presence of the middle group (178.6 cm) peaked by the quarter (26.9%), whereas the largest group had the lowest attendance by 7.6%.
The variance of the H.S.I.
started by 20.8% to drop in the middle (15.2%) raising to 25.7% in the largest specimens.
G.S.I.
averages of males and females indicated gradually from 1.20 and 1.00 in the small sizes, till 4.31 and 4.82, respectively.
The sex ratio of males and females approached by 1.33: 1.00 respectively.
Their stomachs contained pelagic teleosts (44.6%) then mollusks by 20.3 %, with the benthic fishes, cephalopods and juvenile cartilaginous fishes constituted by 17.6, 9.4 and 8.1% respectively.
Pelagics peaked in 113.9 cm by 65.0% and dropped (30.4%) in 229.1 cm; in 77.6 cm, the bony benthics and cartilaginous fishes recorded 52.2 and 14.6% respectively, with 16.7 of mollusks, compare to 29.8% in 178.6 cm, cephalopods peaked to 20.0% in 145.8cm.
This study is beneficial for studies the population dynamics of this species and others in the Libyan coast, to manage the fish stocks-assessment and to protect the immature individuals in coasts and nursery grounds from overfishing.
Data Type
Conference Papers
Record ID
BIM-1456977
American Psychological Association (APA)
Bu Zayd, Isam Mahmud Khamis& Birfad, Muhammad Ayyad. 2021-12-31. Fisheries and biology of spinner shark Carcharhinus brevipinna in Ras-Lanuf shores, Libya-spring and summer 2019. . Vol. 3, no. 1 (Special issue) (Dec. 2021), pp.78-99.مصراتة، ليبيا : جامعة مصراتة، كلية الزراعة،.
https://search.emarefa.net/detail/BIM-1456977
Modern Language Association (MLA)
Bu Zayd, Isam Mahmud Khamis& Birfad, Muhammad Ayyad. Fisheries and biology of spinner shark Carcharhinus brevipinna in Ras-Lanuf shores, Libya-spring and summer 2019. . مصراتة، ليبيا : جامعة مصراتة، كلية الزراعة،. 2021-12-31.
https://search.emarefa.net/detail/BIM-1456977
American Medical Association (AMA)
Bu Zayd, Isam Mahmud Khamis& Birfad, Muhammad Ayyad. Fisheries and biology of spinner shark Carcharhinus brevipinna in Ras-Lanuf shores, Libya-spring and summer 2019. .
https://search.emarefa.net/detail/BIM-1456977
