Severe coral loss shifts energetic dynamics on a coral reef

Morais, Renato A., Depczynski, Martial, Fulton, Christopher, Marnane, Michael, Narvaez, Pauline, Huertas, Victor, Brandl, Simon J., and Bellwood, David R. (2020) Severe coral loss shifts energetic dynamics on a coral reef. Functional Ecology, 34 (7). pp. 1507-1518.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: https://doi.org/10.1111/1365-2435.13568
 
1


Abstract

1. Declining coral cover and loss of structural complexity are widely reported on today's coral reefs. While coral loss frequently triggers changes in coral reef fish assemblage structure, the ecosystem‐scale consequences of these changes are poorly known.

2. Here we evaluate how four metrics of energy flow and storage that underscore a critical coral reef function, consumer biomass production, respond to severe coral loss on a coral reef in the northern Great Barrier Reef, Australia.

3. We compared fish and benthic surveys at Lizard Island from 2003 to 2004 with surveys in 2018 using an individual‐level modelling approach that integrates growth and mortality coefficients to estimate community‐level standing biomass, productivity, consumed biomass and turnover.

4. In the study period, coral cover declined by 72%–83% in forereef zones while turf cover increased by 18%–100% across all zones. Reef fish assemblages, in turn, responded with a 71% increase in standing biomass, 41% in productivity and 37% in consumed biomass, mainly driven by nominally‐herbivorous fishes (Labridae—Scarini, Acanthuridae and Siganidae). By contrast, biomass turnover rates declined by 19%.

5. Our findings suggest that coral loss can drive energetic shifts on coral reefs, leading to more productive, but slower paced reef fish assemblages. Although the observed build‐up of biomass may appear positive, the decreased turnover rates indicate that the system is unable to maintain biomass replacement levels. This suggests that the enhanced productivity that accompanied coral loss may be driven by storage effects from the somatic growth of individuals already present, questioning the temporal stability of these changes to coral reef ecosystem functioning.

Item ID: 63748
Item Type: Article (Research - C1)
ISSN: 1365-2435
Keywords: coral reef fishes; ecosystem function; fish productivity; reef degradation; standing biomass; turnover
Copyright Information: © 2020 British Ecological Society
Funders: Australian Research Council (ARC), Lizard Island Reef Research Foundation (LIRRF), James Cook University (JCU)
Projects and Grants: LIRRF Doctoral Fellowship, JCU Postgraduate Research Scholarship
Date Deposited: 21 Jul 2020 04:50
FoR Codes: 05 ENVIRONMENTAL SCIENCES > 0501 Ecological Applications > 050102 Ecosystem Function @ 34%
06 BIOLOGICAL SCIENCES > 0602 Ecology > 060205 Marine and Estuarine Ecology (incl Marine Ichthyology) @ 33%
07 AGRICULTURAL AND VETERINARY SCIENCES > 0704 Fisheries Sciences > 070499 Fisheries Sciences not elsewhere classified @ 33%
SEO Codes: 96 ENVIRONMENT > 9608 Flora, Fauna and Biodiversity > 960808 Marine Flora, Fauna and Biodiversity @ 100%
Downloads: Total: 1
Last 12 Months: 1
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page