Biodiversity aspects of Common Torpedo (Torpedo torpedo) in by-catch in Sidi Sha’ab Harbour, Tripoli, Libya

Document Type : Research paper


Department of Zoology, Faculty of Science, Omar Al-Mukhtar University, Al-Bayda, Libya


Forty-four specimens of the common torpedo (Torpedo torpedo) were collected from the discarded catch of long-line boat’s haul from Sidi Sha’ab harbor of Tripoli (May 2016) and used for establishing biodiversity and morphometric traits of the fish. The specimens ranged in size from 13.3 to 68.2 cm and in total weight from 92.61 to 989.25 g. The results revealed that the value of the constant b of the length-weight relationship was 1.9064 that indicated negative allometric growth (b< 3). The condition factors of Kf and Kc decreased progressively from 2.54 and 1.82 in the smallest fish size group (17.2 cm) to the largest one (67.5 cm) which recorded a rare value of (Kf = 0.32 and Kc = 0.25), respectively. The length-frequency distribution indicated that the youngest size-group (17.2 cm) peaked at a quarter of the studied samples. Biodiversity and Morphometric traits of the torpedo were related to total length as percentage ratios. Disk length and diameter were larger in females (48.6 and 43.0%) than in males (47.4 and 41.2%).

Graphical Abstract

Biodiversity aspects of Common Torpedo (Torpedo torpedo) in by-catch in Sidi Sha’ab Harbour, Tripoli, Libya


  • The Mediterranean Sea is known to encompass a high diversity of important habitats threatened nowadays.
  • In Libya, fish are essential component of coast, which constitutes 36% of the Arabic Mediterranean coasts.
  • The present study is of the first studies in the biology of elasmobranches in Libya.
  • More studies are required to create good database for elasmobranches in this region.


Main Subjects

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