First in situ record of the deep-sea shark Hexanchus griseus (Chondrichthyes: Hexanchidae) off Rapa Nui (Easter Island, Chile), and management implications

Abstract

The conservation of threatened sharks requires defining the occurrence and distribution range of the species and key habitats for their survival. During surveys of mesophotic and deeper benthic habitats (50 to 340 m depth) off Rapa Nui (Easter Island, Chile, southeastern Pacific), using a remotely operated vehicle, a male bluntnose sixgill shark, Hexanchus griseus (Hexanchidae), was sighted. The estimated total length of this immature specimen was ~146 cm. This is the first documented record of the species off Rapa Nui. The in situ evidence of this threatened deep-water shark highlights the urgency to build management strategies to protect vulnerable apex predators of coastal and deep-waters ecosystems of the recently created Rapa Nui Marine Protected Area for Multiple Uses, above all from the effects of fisheries and other human activities (e.g. bycatch, marine litter).