On the Challenges of Identifying Benthic Dominance on Anthropocene Coral Reefs

Sterling B Tebbett; Samantha K Crisp; Richard D Evans; Christopher J Fulton; Albert Pessarrodona; Thomas Wernberg; Shaun K Wilson; David R Bellwood

doi:10.1093/biosci/biad008

On the Challenges of Identifying Benthic Dominance on Anthropocene Coral Reefs

Bioscience. 2023 Mar 1;73(3):220-228. doi: 10.1093/biosci/biad008. eCollection 2023 Mar.

Authors

Sterling B Tebbett¹, Samantha K Crisp¹, Richard D Evans^{2

3}, Christopher J Fulton^{3

4}, Albert Pessarrodona⁵, Thomas Wernberg⁵, Shaun K Wilson^{2

3}, David R Bellwood¹

Affiliations

¹ Research Hub for Coral Reef Ecosystem Functions, with the College of Science and Engineering, and with the ARC Center of Excellence for Coral Reef Studies, James Cook University, Townsville, Queensland, Australia.
² Department of Biodiversity, Conservation, and Attractions, Kensington, Western Australia, Australia.
³ UWA Oceans Institute, University of Western Australia, Crawley, Western Australia, Australia.
⁴ Australian Institute of Marine Science, Indian Ocean Marine Research Centre, Crawley, Western Australia, Australia.
⁵ UWA Oceans Institute, School of Biological Sciences, University of Western Australia, Crawley, Western Australia, Australia.

Abstract

The concept of dominance is frequently used to describe changes in rapidly reconfiguring ecosystems, but the definition of dominance can vary widely among studies. Using coral reefs as a model, we use extensive benthic composition data to explore how variability in applying dominance concepts can shape perceptions. We reveal that coral dominance is sensitive to the exclusion of key algal groups and the categorization of other benthic groups, with ramifications for detecting an ecosystem phase shift. For example, ignoring algal turf inflates the dominance of hard and soft corals in the benthic habitats underpinning reef ecosystems. We need a consensus on how dominance concepts are applied so that we can build a more comprehensive understanding of ecosystem shifts across a broad range of aquatic and terrestrial settings. For reefs, we highlight the benefits of comprehensive and inclusive surveys for evaluating and managing the altered ecosystem states that are emerging in the Anthropocene.

Keywords: algal turf; benthic dominance; coral reef; macroalgae; phase shift.