Thesis: Comparing and contrasting environmental drivers of horizontal and vertical spaces us by grey reef and silvertip sharks in a large atoll reef system.
My research uses electronic tagging techniques to gather fine scale horizontal and vertical space use data on two reef shark species, the grey reef shark (Carcharhinus amblyrhynchos) and the silvertip shark (Carcharhinus alabimarginatus). These data are used to determine similarities and differences in the species' use of monitored reef sites, and to model their respective responses to environmental drivers. Additionally, archival tagging of silvertip sharks provides high resolution data on their vertical space use, particularly with respect to water temperature, allowing their diving behaviour and thermal niche to be investigated in detail.
Why my research is important
Grey reef and silvertip sharks are familiar to divers at reefs throughout the Indo-Pacific, but knowledge of their spatial ecology is still incomplete. This limits our ability to manage populations threatened or impacted by fisheries, and to predict the effects of future climate change scenarios, including warming of the tropical oceans, on these species.
These larger reef shark species provide key services in regulating their host ecosystems, as well as functionally linking reef and pelagic systems through movement and predation. Improving our knowledge of their spatial use will provide insights into their ecosystem roles, as well as allowing us to predict and perhaps ameliorate their vulnerability to fishing and changing oceanography in an increasingly populated and warming world.