Full text not available from this repository.

Abstract

Global warming is markedly changing diverse coral reef ecosystemsthrough an increasing frequency and magnitude of mass bleachingevents. How local impacts scale up across affected regionsdepends on numerous factors, including patchiness in coralmortality, metabolic effects of extreme temperatures on populationsof reef-dwelling species4 and interactions between taxa. Here weuse data from before and after the 2016 mass bleaching event toevaluate ecological changes in corals, algae, fishes and mobileinvertebrates at 186 sites along the full latitudinal span of the GreatBarrier Reef and western Coral Sea. One year after the bleachingevent, reductions in live coral cover of up to 51% were observedon surveyed reefs that experienced extreme temperatures; however,regional patterns of coral mortality were patchy. Consistent declinesin coral-feeding fishes were evident at the most heavily affectedreefs, whereas few other short-term responses of reef fishes andinvertebrates could be attributed directly to changes in coral cover.Nevertheless, substantial region-wide ecological changes occurredthat were mostly independent of coral loss, and instead appeared tobe linked directly to sea temperatures. Community-wide trophicrestructuring was evident, with weakening of strong pre-existinglatitudinal gradients in the diversity of fishes, invertebrates and theirfunctional groups. In particular, fishes that scrape algae from reefsurfaces, which are considered to be important for recovery afterbleaching, declined on northern reefs, whereas other herbivorousgroups increased on southern reefs. The full impact of the 2016bleaching event may not be realized until dead corals erode duringthe next decade. However, our short-term observations suggestthat the recovery processes, and the ultimate scale of impact, areaffected by functional changes in communities, which in turndepend on the thermal affinities of local reef-associated fauna. Suchchanges will vary geographically, and may be particularly acute atlocations where many fishes and invertebrates are close to theirthermal distribution limits.

Item Type:	Article
Authors/Creators:	Stuart-Smith, RD and Brown, CJ and Ceccarelli, DM and Edgar, GJ
Keywords:	Reef Life Survey, long-term monitoring, reef fish, climate change, citizen science
Journal or Publication Title:	Nature
Publisher:	Nature Publishing Group
ISSN:	0028-0836
DOI / ID Number:	https://doi.org/10.1038/s41586-018-0359-9
Copyright Information:	Copyright 2018 Springer Nature Limited
Related URLs:	Google Scholar: Stuart-Smith, RD UTAS Profile: Stuart-Smith, RD Google Scholar: Edgar, GJ UTAS Profile: Edgar, GJ
Item Statistics:	View statistics for this item

Actions (login required)

Item Control Page