Sensing coral reef connectivity pathways from space

Coral reefs rely on inter-habitat connectivity to maintain gene flow, biodiversity and ecosystem resilience. Coral reef communities of the Red Sea exhibit remarkable genetic homogeneity across most of the Arabian Peninsula coastline, with a genetic break towards the southern part of the basin. While previous studies have attributed these patterns to environmental heterogeneity, we hypothesize that they may also emerge as a result of dynamic circulation flow; yet, such linkages remain undemonstrated. Here, we integrate satellite-derived biophysical observations, particle dispersion model simulations, genetic population data and ship-borne in situ profiles to assess reef connectivity in the Red Sea. We simulated long-term (>20 yrs.) connectivity patterns driven by remotely-sensed sea surface height and evaluated results against estimates of genetic distance among populations of anemonefish, Amphiprion bicinctus, along the eastern Red Sea coastline. Predicted connectivity was remarkably consistent with genetic population data, demonstrating that circulation features (eddies, surface currents) formulate physical pathways for gene flow. The southern basin has lower physical connectivity than elsewhere, agreeing with known genetic structure of coral reef organisms. The central Red Sea provides key source regions, meriting conservation priority. Our analysis demonstrates a cost-effective tool to estimate biophysical connectivity remotely, supporting coastal management in data-limited regions.

Citation

Raitsos DE, Brewin RJW, Zhan P, Dreano D, Pradhan Y, et al. (2017) Sensing coral reef connectivity pathways from space. Scientific Reports 7. Available: http://dx.doi.org/10.1038/s41598-017-08729-w.

Acknowledgements

The authors would like to thank the captain and the crews of the R/V “Aegaeo” of the Hellenic Centre for Marine Research (HCMR), and Woodshole Oceanographic Institute (WOI) who made the data collection possible during the Research Cruises Expedition Programme of the Red Sea Research Center at KAUST (RSRC, subject to genetic data). The Ssalto/Duacs altimeter products were produced and distributed by the Copernicus Marine and Environment Monitoring Service (CMEMS) (http://www.marine.copernicus.eu). We thank Giorgio Dall’Olmo and John Gittings for comments provided on an early version of the manuscript, and Trevor Platt, Shubha Sathyendranath and Michael Berumen for useful discussions. We thank Marie-Fanny Racault for re-gridding the coral reef locations. We thank the reviewers for their constructive comments. This research was initiated at the King Abdullah University for Science and Technology (KAUST) in 2012, and completed at Plymouth Marine Laboratory, United Kingdom. This publication is based upon work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under Award No. 3268, and was also partially supported by the UK National Centre for Earth Observation (NCEO). The research made use of the resources of the Supercomputing Laboratory and computer clusters at KAUST.