Ecosystem regime shifts disrupt trophic structure

Hempson, Tessa N. and Graham, Nicholas Anthony James and MacNeil, M. Aaron and Hoey, Andrew S. and Wilson, Shaun (2018) Ecosystem regime shifts disrupt trophic structure. Ecological Applications, 28 (1). pp. 191-200. ISSN 1051-0761

[img]
Preview
PDF (Hempson_TrophicStructure_submitted)
Hempson_TrophicStructure_submitted.pdf - Submitted Version

Download (606kB)
[img]
Preview
PDF (Hempson_et_al-2017-Ecological_Applications)
Hempson_et_al_2017_Ecological_Applications.pdf - Accepted Version
Available under License Creative Commons Attribution-NonCommercial.

Download (934kB)

Abstract

Regime shifts between alternative stable ecosystem states are becoming commonplace due to the combined effects of local stressors and global climate change. Alternative states are characterised as substantially different in form and function to pre-disturbance states, disrupting the delivery of ecosystem services and functions. On coral reefs, regime shifts are typically characterised by a change in the benthic composition from coral- to macroalgal-dominance. Such fundamental shifts in the benthos are anticipated to impact associated fish communities that are reliant on the reef for food and shelter, yet there is limited understanding of how regime shifts propagate through the fish community over time, relative to initial or recovery conditions. This study addresses this knowledge gap using long-term data of coral reef regime shifts and recovery on Seychelles reefs following the 1998 mass bleaching event. It shows how trophic structure of the reef fish community becomes increasingly dissimilar between alternative reef ecosystem states (regime-shifted vs recovering) with time since disturbance. Regime-shifted reefs developed a concave trophic structure, with increased biomass in base trophic levels as herbivorous species benefitted from increased algal resources. Mid trophic level species, including specialists such as corallivores, declined with loss of coral habitat, while biomass was retained in upper trophic levels by large-bodied, generalist invertivores. Recovering reefs also experienced an initial decline in mid trophic level biomass, but moved towards a bottom-heavy pyramid shape, with a wide range of feeding groups (e.g. planktivores, corallivores, omnivores) represented at mid trophic levels. Given the importance of coral reef fishes in maintaining the ecological function of coral reef ecosystems and their associated fisheries, understanding the effects of regime shifts on these communities is essential to inform decisions that enhance ecological resilience and economic sustainability.

Item Type:
Journal Article
Journal or Publication Title:
Ecological Applications
Additional Information:
Copyright by the Ecological Society of America. This is the peer reviewed version of the following article: Hempson, T. N., Graham, N. A. J., MacNeil, M. A., Hoey, A. S. and Wilson, S. K. (2018), Ecosystem regime shifts disrupt trophic structure. Ecol Appl, 28: 191–200. doi:10.1002/eap.1639 which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1002/eap.1639/abstract This article may be used for non-commercial purposes in accordance With Wiley Terms and Conditions for self-archiving.
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/2300/2303
Subjects:
ID Code:
89066
Deposited By:
Deposited On:
06 Dec 2017 14:18
Refereed?:
Yes
Published?:
Published
Last Modified:
20 Sep 2020 04:31