Infrequent Records and Fisheries Interactions of the Near-Threatened Bluntnose Sixgill Shark (Hexanchus griseus Bonnaterre, 1788) in the Mediterranean Waters of the Gaza Strip, Palestine
Abdel Fattah N. Abd Rabou *
Department of Biology and Biotechnology, Faculty of Science, Islamic University of Gaza, P.O. Box 108, Gaza Strip, Palestine.
*Author to whom correspondence should be addressed.
Abstract
The Bluntnose Sixgill Shark (Hexanchus griseus Bonnaterre, 1788) is a deep-sea elasmobranch classified as Near Threatened by the IUCN, with limited ecological information available from the southeastern Mediterranean. This study documents infrequent records and fisheries interactions of the species in the coastal waters of the Gaza Strip, Palestine, over an approximate 20-year period. Data were collected through field surveys at landing sites and fish markets, supported by interviews with fishermen, fisheries authority records, and opportunistic photographic documentation. Fewer than 15 individuals of the Bluntnose Sixgill Shark, locally known as “Cowlie”, were recorded, confirming the species’ rarity and sporadic occurrence in the region. All specimens were identified based on distinctive morphological features, particularly the presence of six pairs of gill slits and posteriorly positioned dorsal fin. Observed individuals ranged from subadults to large adults, with reported total lengths exceeding 3 m. Capture events were exclusively incidental, primarily associated with bottom-set longlines deployed in deeper offshore waters, with occasional records from trammel nets. No seasonal or spatial patterns were detected, and all captured specimens were retained for local consumption, reflecting their economic value and the absence of regulatory measures. The rarity of records is consistent with the species’ deep-water ecology and limited overlap with coastal artisanal fisheries. However, its intrinsic vulnerability, combined with unregulated bycatch retention, raises potential conservation concerns. This study provides the first consolidated account of the Bluntnose Sixgill Shark in the Gaza Strip waters and highlights the importance of fisheries-dependent data and local ecological knowledge in addressing data gaps for deep-sea elasmobranchs in understudied regions. Enhanced monitoring and targeted research are recommended to support conservation and management efforts in the southeastern Mediterranean.
Keywords: Bluntnose Sixgill Shark, Hexanchus griseus, elasmobranchs, bycatch, fisheries interactions, conservation, Gaza Strip, Palestine, southeastern Mediterranean.