Since August 2018, the Great Barrier Reef in the ocean off Australia has had a special protector — an autonomous underwater drone called RangerBot that has monitored the status of the reef and protected the corals from the predatory crown-of-thorns starfish. But now researchers at Queensland University of Technology (QUT), Australia have announced that the RangerBot has a new mission: it is to be rechristened “LarvalBot” and will be repurposed to spread coral babies.
Scientists have collected hundreds of millions of coral spawn from the surviving corals of the Great Barrier Reef which have not yet succumbed to coral bleaching. These spawn are then reared into baby corals in special floating enclosures, and once they have grown large enough to survive on their own, they are delivered by the LarvalBot to a designated location in the reef. If necessary, many coral larvae can be distributed at once in a “larval cloud” that can blanket an entire damaged area of a reef. This technique is called larval restoration and may be reef’s best hope for the future.
The next large-scale spawning of the coral is planned for late November, and with the help of LarvalBot, the coral larvae should be able to spread up to 100 times faster than they could alone. Two or three robots will carry a combined 1.4 million larvae which they will disperse over an area of 1,500 square meters per hour per robot. This intervention is necessary because of the huge damage inflicted on coral reefs due to climate change, which has lead to massive deaths of reefs around the world and in Australia in particular. Especially concerning is the phenomenon of coral bleaching, where rising sea temperatures cause corals to lose their symbiotic algae and therefore lose their color, killing the corals outright if left unchecked.
The leader of the robotics team at QUT, Professor Matthew Dunbabin from the Institute for Future Environments, is optimistic about the possibilities of the bot technology. “This has the potential to revolutionize coral restoration on reefs worldwide,” he said in a statement shared by the university. “Whilst this is new, we have trialled the different technologies and are confident of its success.”