Record of a bull ray Aetomylaeus bovinus (Myliobatidae) in a sea-cage tuna farm in the Aegean coast of Türkiye (Eastern Mediterranean Sea)

10/17/2023 Arda Tonay

Record of a bull ray Aetomylaeus bovinus (Myliobatidae) in a sea-cage tuna farm in the Aegean coast of Türkiye (Eastern Mediterranean Sea) 

Evrim Kurtay, Okan Akyol, Aytaç Özgül, Christian Capapé

ORCID IDs: E.K. 0000-0002-7234-8407; O.A. 0000-0001-7738-2156; A.Ö. 0000-0001-7706-9012; C.C. 0000-0002-6630-2728

Faculty of Fisheries, Ege University 35440 Urla, İzmir, TÜRKİYE
Laboratoire d’Ichtyologie, Université de Montpellier, 34095 Montpellier, FRANCE

Abstract 

A specimen of bull ray Aetomylaeus bovinus was captured dead by a diver around a tuna sea cage farm. It was female, measured 2310 mm in total length (TL) and 1460 mm in disc width (DW) with body weight estimated as about 20 kg. This case was reported from a tuna farm for the first time. The bull ray entered the sea cage about three months ago, but no attack occurred to the tuna in the cage. It was grazing on fouling organisms that attached to the nets. However, the cage nets were replaced with clean ones four days ago before the capture, and the bull ray did not find enough fouling organisms or uneaten fish feed and was starved to death.

Keywords: Aetomylaeus bovinus, sea-cage farm, predators, biodiversity, nutrition

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