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

Feeding coral larvae increases settlement and early post-settlement survival (#322)

Colleen Rodd 1 , Steve Whalan 1 , Peter Harrison 1
  1. Southern Cross University, Lismore Heights, NSW, Australia

Intensifying anthropogenic impacts have reduced live coral cover on reefs, impacting key population-level processes such as coral larval settlement and recruitment. Assessing the factors that drive recruitment success in reef-building corals may hold the key to effective coral reef restoration success. Early life stages represent a bottleneck in recruitment processes. Larval energetics strongly impact recruitment in reef-building corals. Coral larvae have long been classed as non-feeding, believed to gain all their nutrition from internal energy reserves. These energy reserves are limiting factors in settlement success and early-post settlement survival. Some coral larvae have been shown to uptake excess nutrients from the water column. The impact of these exogenous nutrients on larval settlement and early post-settlement survival is poorly understood. This talk will present results that quantify the effect of larval feeding on coral larvae settlement and early post-settlement survival. An ex-situ experiment using Acropora tenuis and Acropora millepora demonstrated that feeding larvae significantly enhanced settlement and had an immediate positive effect on spat survival in both species. Therefore, enhancing settlement and early post-settlement survival by feeding larvae has the potential to improve the effectiveness of restoration efforts and provide a pathway for degraded reefs to recover.