During their week on the water, the researchers visited the remote Ribbon Reef section of the GBR, where they surveyed 120 sites across 45 reefs and captured over 11 thousand images.
“We surveyed many areas that aren’t currently being monitored as part of regular programs. Capturing a snapshot of reef conditions with imagery is an approach that hasn’t really been used in this way before. We hope it can provide complementary information to the existing detailed monitoring done at a smaller number of sites,” Katie says.
The team used the trip as an opportunity to trial different methods for mapping sea cucumber populations, which will eventually help establish new monitoring programs.
“There is uncertainty around the status of sea cucumber populations on the GBR, despite the importance of these animals and their role in reef health. We helped collect some early data and trialled new methods to feed into the monitoring design in some shallower reef top areas,” Katie says.
“We invited researchers like Dr Karen Joyce, an expert in remote sensing and aerial drone surveys of reef tops, to join our expedition. We want to team up with other researchers to maximise what we collect while we are out on these trips. The most costly part of research and monitoring the Reef is vessel time, and expeditions like this create an opportunity to share what is often the biggest cost to any research program. ”
On the expedition, the team also mapped seagrass populations. There is more seagrass covering the GBR than there is coral, and seagrass meadows play a vital role in the marine ecosystem. Not only do they provide habitat for numerous organisms, but they also help filter the water of sediments and nutrients from land-based runoff.
Deepwater seagrass meadows within the GBR are notoriously difficult to map, and can extend down to water depths of around 50 metres.
“Seagrasses are incredibly valuable and often overlooked, historically, by the broader community. They’re critical nursery grounds for many fisheries and recently a big focus has been on their ability to capture and store carbon for long periods of time. In fact, research suggests they do it better than their terrestrial counterparts like forests, but much work is still needed to understand how deepwater seagrasses of the GBR contribute to carbon storage,” Katie says.
“Great Reef Census, with its scalability, presents an opportunity to look at these important components of the World Heritage Area and start capturing this more challenging information.”