EGU21-959
https://doi.org/10.5194/egusphere-egu21-959
EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

Modelling coral reef connectivity in the SW Indian Ocean

Noam Vogt-Vincent1, Helen Johnson1, and April Burt2
Noam Vogt-Vincent et al.
  • 1Department of Earth Sciences, University of Oxford, Oxford, United Kingdom
  • 2Department of Plant Sciences, University of Oxford, Oxford, United Kingdom

Coral larvae can be transported over great distances by ocean currents, establishing ecological and genetic connectivity between distal coral reefs. Understanding these patterns of connectivity and how they vary through time is essential for effective marine spatial planning, particularly in the SW Indian Ocean which is an under-studied region. However, tracking coral larval dispersal directly is generally unfeasible due to their size, necessitating indirect observations or numerical models. We have developed a regional configuration of the Coastal and Regional Ocean Community Model (CROCO) in the SW Indian Ocean at 1/50o, spanning from the East African coast to the Chagos Archipelago, to simulate surface currents and gain insight into likely coral larval dispersal pathways and connectivity. The configuration is forced by the ERA-5 atmospheric reanalysis at the surface, and the 1/12o CMEMS GLORYS12V1 reanalysis and barotropic tides at the lateral ocean boundaries. We will be carrying out a 25-year interannual simulation and a climatological control simulation. Using lagrangian particle tracking, we will estimate patterns of connectivity between reef sites across the region (with a particular focus on connectivity across Seychelles), and how significant and predictable the temporal variability in connectivity is. Early progress towards this goal will be presented. The longer-term ambition of this project is to assess our predicted connectivity against independent connectivity estimates from genetic studies and previous regional simulations at a lower resolution.

How to cite: Vogt-Vincent, N., Johnson, H., and Burt, A.: Modelling coral reef connectivity in the SW Indian Ocean, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-959, https://doi.org/10.5194/egusphere-egu21-959, 2021.