Photographic documentation of tope shark, Galeorhinus galeus (Linnaeus, 1758), in the Istanbul Strait: Reoccurrence of a rare shark in troubled waters

Hakan Kabasakal, Kenan Fuat Türetken

ORCID ID: 0000-0001-8189-9748

Ichthyological Research Society, Tantavi mahallesi, Menteşoğlu caddesi, İdil apt., No: 30, D: 4, TR-34764 Ümraniye, İstanbul, TURKEY

Abstract

On 6 June 2021, a specimen of Galeorhinus galeus (Linnaeus, 1758), was sighted off Balat coast (Golden Horn, Istanbul Strait, Turkey). In the current IUCN Red List assessment of G. galeus, it is considered as a “Critically Endangered” species in the Mediterranean Sea. In accordance with the current fisheries law numbered 1380, G. galeus is under full protection in Turkish seas. Although the present encounter of tope shark in the Golden Horn confirmed the current existence of G. galeus in the Marmara Sea, one of the main threats to the sharks’ survival in this marine region is habitat degradation. A non-invasive and non-destructive method for data collection, legitimating the reasonable use of alternative source of data, like video footage recorded by citizen scientists, is urgently needed for the research of endangered shark species such as G. galeus.

Keywords: Tope shark, Galeorhinus, Triakidae, Marmara, Istanbul, conservation

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