Pumice rafts and reef connectivity: invasions, restocking and expansion of the Great Barrier Reef

Coral reefs are global features of tropical shallow marine environments, representing biodiversity hot spots and providing invaluable environmental, social and economic benefits. Reef colonisation is challenged by larval dispersal because of the distances required, the high failure and mortality rates, and a tendency for local recruitment of larvae. The solution is the dispersal of coral reef building organisms via floating objects and pumice, produced by explosive volcanic eruptions – a natural and frequent mass transit process operating in our world’s oceans. The rafting of shallow marine organisms fundamentally changes the dispersal range limitations, and is able to overcome deep expansive ocean barriers. Pumice rafting provides lines of communication for reef-building organisms for the Great Barrier Reef and across the southwest Pacific, and is a natural process with the potential to restock damaged reefs. The research focuses on constraining the frequency, trajectory, rate, biomass and biodiversity of transfer via pumice rafts to the Great Barrier Reef, and also assessing the biosecurity implications (e.g. marine pest invasions) by this process.