Chapters from the life story of common angel shark, Squatina squatina, from Turkish waters: a historical, ethnoichthyological and contemporary approach to a little-known shark species

Chapters from the life story of common angel shark, Squatina squatina, from Turkish waters: a historical, ethnoichthyological and contemporary approach to a little-known shark species

Hakan Kabasakal

ORCID ID: 0000-0001-8189-9748

Ichthyological Research Society, Tantavi mah., Menteşoğlu cad., İdil ap., No: 30, D: 4, 34764 Ümraniye, İstanbul, TURKEY

Abstract

This is a case study of integrating historical data, folk knowledge and contemporary survey findings to provide a better understanding of a little-known shark species, Squatina squatina, of which our current knowledge is mostly based on opportunistic research on sporadic specimens. Collected data show the beginning of a clear decline of the species in the 1960s and early 1970s, particularly in the Sea of Marmara. However, there are a substantial number of reports that the species aggregates seasonally, especially in winter, in certain regions (hot spots) along the Turkish coast. Large (>200 cm TL) specimens of S. squatina also occurred in Turkish waters until the early 1980s. Squatina squatina is a critically endangered shark. Its seasonal aggregations may result in the perception of “false abundance” in the mindset of fishermen or divers, which may trigger the fishery of the common angel shark. Therefore, effective conservation of angel sharks clearly demands an integrated management plan, including a fishing ban and habitat protection, where the angel sharks are known to aggregate seasonally.

Keywords: Chondrichthyans, Squatinidae, aggregations, hot spots, conservation, management

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