Short Talk (7,5 mins) Australian Marine Sciences Association 2022

Growth Rates of High Latitude Corals in Western Australia (#55)

Megan R Proctor 1 , Karen Filbee-Dexter 1 , Defne Sahin 1 , Thomas Wernberg 1
  1. The Oceans Institute and School of Biological Sciences , University of Western Australia, Crawley, WA, Australia

A tropicalization of our oceans is occurring globally as warm affiliated marine species move poleward as a result of ocean warming. This trend is observed in central and southwestern coast of Western Australia, a biogeographical overlap zone of temperate and tropical species. The distribution of the benthic community composition in this region, particularly canopy-forming seaweeds and corals, are undergoing changes as a result of warming oceans and extreme heatwave events. Following a 2011 marine heatwave off the west coast of Australia, there was a significant loss in kelp forest cover and an increase in turf algae and coral abundance. A significant shift in the size distribution of Plesiastrea versipora signalled greater success of new coral recruits after the heatwave. This research aims to determine: What are the growth rates of the most abundant coral species on the southwestern coast of Western Australia? How are coral growth rates related to changes in mean sea surface temperature (SST) and regional temperature anomalies? Identified as a global “hotspot” for ocean warming, determining local growth rates and their relationship to SST will provide valuable baseline data for coral communities in this region.