Environmental and anthropogenic effects impact species abundance, density and distribution

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Investigating and comparing the spatial ecology of two coastal-pelagic shark species at Ascension Island: a remote UK Overseas Territory that is surrounded by one of the world's largest marine protected areas (MPA). Sharks have been legally protected at Ascension Island since 2017. Recently, however, increasingly regular, and unexplained movements of Galapagos sharks (Carcharhinus galapagensis) into shallow, coastal habitats have created significant conflicts with fishers and other recreational ocean users which threaten to undermine support for the MPA. Preliminary work by the supervisory team has identified several apparent hotspots around Ascension Island that frequently support mixed species 'super schools' of Galapagos and silky sharks (Carcharhinus falciformis). However, the significance of these sites and drivers of temporal variability in shark distributions - including aggregating behaviours and periodic inshore movements of Galapagos sharks - are currently unknown. Addressing this knowledge gap has been identified as a priority in the Ascension Island MPA Research Strategy.