Among-site variability in the stochastic dynamics of East African coral reefs

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1 School of Environmental Sciences, University of Liverpool, Liverpool, United Kingdom
2 Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
3 Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States
4 School of Mathematical and Computer Sciences, Actuarial Mathematics and Statistics, Heriot-Watt University, Edinburgh, United Kingdom
5 Wildlife Conservation Society, New York, United States
6 Department of Mathematical Sciences, University of Liverpool, Liverpool, United Kingdom
DOI
10.7287/peerj.preprints.2687v1
Published
Accepted
Subject Areas
Biophysics, Ecology, Marine Biology
Keywords
vector autoregressive model, state-space model, stochastic dynamics, community composition, spatial variability, temporal variability, coral reef, Bayesian statistics
Copyright
© 2017 Allen et al.
Licence
This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
Cite this article
Allen KA, Bruno JF, Chong F, Clancy D, McClanahan TR, Spencer M, Zychaluk K. 2017. Among-site variability in the stochastic dynamics of East African coral reefs. PeerJ Preprints 5:e2687v1

Abstract

Coral reefs are dynamic systems whose composition is highly influenced by unpredictable biotic and abiotic factors. Understanding the spatial scale at which long-term predictions of reef composition can be made will be crucial for guiding conservation efforts. Using a 22-year time series of benthic composition data from 20 reefs on the Kenyan and Tanzanian coast, we developed Bayesian vector autoregressive state-space models for reef dynamics, incorporating among-site variability, and quantified their long-term behaviour. We estimated that if there were no among-site variability, the total long-term variability would be approximately one third of its current value. Thus, our results showed that among-site variability contributes more to long-term variability in reef composition than does temporal variability. Individual sites were more predictable than previously thought, and predictions based on current snapshots are informative about long-term properties. Our approach allowed us to identify a subset of possible climate refugia sites with high conservation value, where the long-term probability of coral cover \(\leq\) 0.1 was very low. Analytical results show that this probability is most strongly influenced by among-site variability and by interactions among benthic components within sites. These findings suggest that conservation initiatives might be successful at the site scale as well as the regional scale.

Author Comment

This is a submission to PeerJ for review.

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