Oral Presentation Australian Society for Fish Biology Conference 2017

Direct versus indirect effects of climate change on coral reef fishes (#127)

Morgan S Pratchett 1 , Cassandra A Thompson 1 , Andrew S Hoey 1 , Shaun K Wilson 2
  1. James Cook University, Townsville, QLD, Australia
  2. Department of Parks and Wildlife, Western Australia State Government, Perth, Western Australia, Australia

Climate change is firmly established as the single greatest threat to coral reef ecosystems. Coral reef fishes are now being affected by changes in environmental conditions (mainly increasing temperature) as well as climate-induced habitat degradation. This study revisits and revises meta-analyses that were initiated following the 1998 global mass-bleaching phenomenon to explore the responses of fishes to sustained and ongoing climate impacts. Despite the emergence of direct environmental impacts on the distribution and performance of reef fishes, habitat degradation (including coral loss and topographical collapse) remains the principal causes of declining abundance, biomass, and biodiversity of reef fishes. Moreover, degradation of reef habitats reduces the capacity for fishes to mediate exposure to changing environmental conditions, making them even more vulnerable to climate impacts. The few species that appear to flourish in the aftermath of climate-induced changes in environmental conditions and habitat structure are small-bodied and short-lived. Sustained degradation of coral reef habitats due to increasing frequency and severity of mass coral bleaching episodes will, therefore, jeopardise the strcuture and function of reef fish assemblages.