Diving behavior of the giant devil ray in the Mediterranean Sea

Published online on 11. August 2011

Simonepietro Canese, Andrea Cardinali, Teresa Romeo, Michela Giusti, Eva Salvati, Michela Angiolillo, Silvestro Greco

ABSTRACT:

The giant devil ray Mobula mobular is the only mobulid species regularly present in the Mediterranean Sea. The spatial ecology and biology of this species are poorly known, and given its high bycatch mortality, low reproductive capacity, and limited range, it is listed as Endangered (A4d) on the IUCN Red List. Most of the information concerning this species has been obtained through bycatch data and opportunistic sightings. To inform conservation and management actions, it is necessary to conduct research on the behavior of giant devil rays. This study is the first attempt to systematically describe the diving behavior of this species. Three specimens were tagged with popup satellite tags in the Messina Strait (central Mediterranean Sea) during summer 2007. Two tags were programmed to detach after 120 d and 1 after 60 d. The data revealed that these fish dove to depths between 600 and 700 m. However, they spent most of their time (81.5%) between the surface and 50 m, in waters with temperatures between 20 and 29°C. The preference for shallow depth and warm surface waters exposes this species to threats such as accidental captures in driftnets and surface longlines.

Endang Species Res 14:171-176

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