Abstract: Pelagic larval dispersal is the main means by which benthic marine organisms can maintain demographic connectivity and gene flow among populations, and is critical for the recovery of reef-building corals that form the structural matrix of coral reef ecosystems. My research investigates connectivity of reef-building corals in Great Barrier Reef (GBR) using several approaches. I am using a multispecies genetic approach for broadcast spawning Acropora species to evaluate common connectivity patterns over a hierarchy of spatial scales based on sampling intensities not previously achieved for the GBR (>6500 colonies from three species representing ~100 sites spanning 14 degrees of latitude). To date I have genotyped >2,000 A. tenuis colonies from 50 reefs throughout the GBR using 12 microsatellite loci. Results show a strong genetic divide between northern and southern GBR reefs, and that most northern and many central GBR populations exchange recruits frequently, whereas populations in the southern GBR are largely self-seeding. I discuss the congruence of these patterns with previous genetic studies for the GBR. Corals have notoriously low genetic diversity and my results indicate that microsatellites are not sufficiently variable to evaluate connectivity using more powerful genetic analyses, such as assignment tests.  As such, I recently developed genomic markers (single nucleotide polymorphisms, SNPs) for three species A. tenuis, A. millepora and A. hyacinthus in order to evaluate fine-scale connectivity using neutral loci as well as loci under selection.

In 2011 Category 5 tropical cyclone Yasi caused massive destruction to exposed reefs in the Palm Islands, central GBR, reducing coral cover to < 5% and completely removed all reproductively mature Acropora colonies, yet sheltered reefs were unaffected by the cyclone. This situation created a natural experiment for evaluating genetic connectivity in the context of information about larval recruitment and high-intensity genetic sampling of A. tenuis in the Palm Islands before the cyclone. I will present results about the impacts of cyclone Yasi on coral recruitment in the Palm Islands, approaches for genetically identifying coral larvae to species and genetically tracking the recovery of coral populations on reefs destroyed by Cyclone Yasi.

Biography: Vimoksalehi (Vee) Lukoschek completed her BSc (Hons) in marine biology, ecology and conservation, and her PhD on the molecular ecology and evolution of sea snakes at JCU in 2007. She continued her genetic research into sea snakes during a 2-year post-doctoral fellowship with Distinguished Prof. John C. Avise at the University of California, Irvine.  In 2010 Vimoksalehi returned to Australia and joined the ARC CoE CRS to work on genetic connectivity in corals on the Great Barrier Reef as a QLD Smart Future Fellow (2010-2013). In 2013 she was awarded an ARC DECRA to develop genomics approaches for investigating larval dispersal and genetic connectivity in the GBR, focusing on the recovery of reefs impacted by cyclone Yasi. Vimoksalehi maintains an interest in the conservation genetics of sea snakes and is currently supervising a PhD student on this topic.