Standard Presentation 2024 Australian Marine Sciences Association Annual Meeting combined with NZMSS

Protecting Great Barrier Reef resilience through effective management of Crown-of-Thorns Starfish outbreaks (#207)

Samuel Matthews 1 , David Williamson 1 , Roger Beeden 1 , Michael Emslie 2 , Rickard Abom 3 , Daniel Beard 4 , Mary Bonin 5 , Peran Bray 2 , Adriana Campili 2 , Daniela Ceccarelli 2 , Leanne Fernandes 1 , Cameron Fletcher 6 , Dan Godoy 7 , Christopher Hemingson 1 , Micehlle Jonker 1 , Bethan Lang 1 , Sheriden Morris 3 , Enrique Mosquera 8 , Gareth Phillips 9 , Tane Sinclair-Taylor 2 , Sascha Taylor 10 , Dieter Tracey 1 , Jeniifer Wilmes 1 , Richard Quincey 1
  1. GBRMPA, Towsnville, QLD, Australia
  2. AIMS, Townsville, QLD, Australia
  3. Reef and Rainforest Research Centre, Cairns, QLD, Au
  4. INLOC Group, Cairns, QLD, Australia
  5. GBRF, Brisbane, QLD, Australia
  6. CSIRO, Townsville, QLD, Australia
  7. Blue Planet Marine, Townsville, QLD, Australia
  8. Pacific Marine Group, Townsville, QLD, Australia
  9. AMPTO, Cairns, QLD, Australia
  10. QPWS, Brisbane, QLD, Australia

Resilience-based management is essential to protect coral reef ecosystems facing the cumulative impacts of Climate Change and human use. Crown-of-thorns Starfish (COTS) are voracious coral predators that periodically reach outbreak densities and cause extensive damage to coral reefs. Here we evaluate the outcomes of the past decade of strategic COTS management in the Great Barrier Reef Marine Park, Australia. We drew upon long-term monitoring data to assess the degree to which targeted COTS control suppressed starfish densities and protected coral across entire reefs and regions (sectors). Compared to the previous outbreak wave, COTS densities were up to six-fold lower and coral cover increased substantially (~44%) in sectors that received timely and sufficient cull effort, while sectors that received limited to no culling effort had sustained COTS outbreaks that caused significant coral losses. Outbreaking reefs that received higher levels of culling effort had net increases in coral cover, while the rate of coral loss was more than halved on reefs with lower levels of cull effort. Our findings demonstrate that proactive, targeted, and sustained COTS control is an effective and scalable tool for resilience-based management action augmenting the benefits of Marine Park Zoning to protect coral and support the Reef’s resilience.