Mesopredator trophodynamics on thermally stressed coral reefs
- 488 Downloads
Ecosystems are becoming vastly modified through disturbance. In coral reef ecosystems, the differential susceptibility of coral taxa to climate-driven bleaching is predicted to shift coral assemblages towards reefs with an increased relative abundance of taxa with high thermal tolerance. Many thermally tolerant coral species are characterised by low structural complexity, with reduced habitat niche space for the small-bodied coral reef fishes on which piscivorous mesopredators feed. This study used a patch reef array to investigate the potential impacts of climate-driven shifts in coral assemblages on the trophodynamics of reef mesopredators and their prey communities. The ‘tolerant’ reef treatment consisted only of coral taxa of low susceptibility to bleaching, while ‘vulnerable’ reefs included species of moderate to high thermal vulnerability. ‘Vulnerable’ reefs had higher structural complexity, and the fish assemblages that established on these reefs over 18 months had higher species diversity, abundance and biomass than those on ‘tolerant’ reefs. Fish assemblages on ‘tolerant’ reefs were also more strongly influenced by the introduction of a mesopredator (Cephalopholis boenak). Mesopredators on ‘tolerant’ reefs had lower lipid content in their muscle tissue by the end of the 6-week experiment. Such sublethal energetic costs can compromise growth, fecundity, and survivorship, resulting in unexpected population declines in long-lived mesopredators. This study provides valuable insight into the altered trophodynamics of future coral reef ecosystems, highlighting the potentially increased vulnerability of reef fish assemblages to predation as reef structure declines, and the cost of changing prey availability on mesopredator condition.
KeywordsClimate change Coral bleaching Functional group Habitat degradation Mesopredator Trophic structure
The authors would like to thank the Lizard Island Research Station and its directors Lyle Vail and Anne Hoggett for all the logistical support and facilities they provided for the field component of this research. This research was conducted under animal ethics approval from James Cook University (Ethics approval number A1996). This research was supported by the Australian Research Council and the Australian Institute for Marine Science.
- Bagenal TB, Tesch FW (1978) Age and growth. In: Bagenal TB (ed) Methods for assessment of fish production in fresh water. Blackwell Scientific Publications, OxfordGoogle Scholar
- Froese R, Pauly D (2016) FishBase, www.fishbase.org, version 10/2016
- Great Barrier Reef Marine Park Authority (2014) Great Barrier Reef Outlook Report 2014. GBRMPA, TownvilleGoogle Scholar
- Hempson TN, Graham NA, MacNeil MA, Bodin N, Wilson SK (2017a) Regime shifts shorten food chains for mesopredators with potential sublethal effects. Func Ecol. https://doi.org/10.1111/1365-2435.13012
- Hempson TN, Graham NA, MacNeil MA, Hoey AS, Wilson SK (2017b) Ecosystem regime shifts disrupt trophic structure. Ecol Appl. https://doi.org/10.1002/eap.1639
- Hoegh-Guldberg O, Mumby PJ, Hooten AJ, Steneck RS, Greenfield P, Gomez E, Harvell CD, Sale PF, Edwards AJ, Caldeira K, Knowlton N, Eakin CM, Iglesias-Prieto R, Muthiga N, Bradbury RH, Dubi A, Hatziolos ME (2007) Coral reefs under rapid climate change and ocean acidification. Science 318:1737–1742CrossRefPubMedGoogle Scholar
- Hughes TP, Kerry JT, Álvarez-Noriega M, Álvarez-Romero JG, Anderson KD, Baird AH, Babcock RC, Beger M, Bellwood DR, Berkelmans R, Bridge TC, Butler IR, Byrne M, Cantin NE, Comeau S, Connolly SR, Cumming GS, Dalton SJ, Diaz-Pulido G, Eakin CM, Figueira WF, Gilmour JP, Harrison HB, Heron SF, Hoey AS, Hobbs J-PA, Hoogenboom MO, Kennedy EV, Kuo C-Y, Lough JM, Lowe RJ, Liu G, McCulloch MT, Malcolm HA, McWilliam MJ, Pandolfi JM, Pears RJ, Pratchett MS, Schoepf V, Simpson T, Skirving WJ, Sommer B, Torda G, Wachenfeld DR, Willis BL, Wilson SK (2017) Global warming and mass bleaching of corals. Nature 543:373–377CrossRefPubMedGoogle Scholar
- Mora C, Aburto-Oropeza O, Ayala-Bocos A, Ayotte PM, Banks S, Bauman AG, Beger M, Bessudo S, Booth DJ, Brokovich E, Brooks A, Chabanet P, Cinner JE, Cortés J, Cruz-Motta JJ, Cupul-Magaña A, DeMartini EE, Edgar GJ, Feary DA, Ferse SCA, Friedlander AM, Gaston KJ, Gough C, Graham NAJ, Green A, Guzman H, Hardt M, Kulbicki M, Letourneur Y, López-Pérez A, Loreau M, Loya Y, Martinez C, Mascareñas-Osorio I, Morove T, Nadon MO, Nakamura Y, Paredes G, Polunin NVC, Pratchett MS, Reyes Bonilla H, Rivera F, Sala E, Sandin SA, Soler G, Stuart-Smith R, Tessier E, Tittensor DP, Tupper M, Usseglio P, Vigliola L, Wantiez L, Williams I, Wilson SK, Zapata FA (2011) Global human footprint on the linkage between biodiversity and ecosystem functioning in reef fishes. PLoS Biol 9:e1000606CrossRefPubMedPubMedCentralGoogle Scholar
- Wernberg T, Bennett S, Babcock RC, de Bettignies T, Cure K, Depczynski M, Dufois F, Fromont J, Fulton CJ, Hovey RK, Harvey ES, Holmes TH, Kendrick GA, Radford B, Santana-Garcon J, Saunders BJ, Smale DA, Thomsen MS, Tuckett CA, Tuya F, Vanderklift MA, Wilson S (2016) Climate-driven regime shift of a temperate marine ecosystem. Science 353:169–172CrossRefPubMedGoogle Scholar