Scientists have captured the first images of deep offshore reefs off the coast of Bruny Island using high-tech underwater robots.
Researchers from the University of Tasmania’s Institute for Marine and Antarctic Studies (IMAS) took more than 61,000 images of three reef systems in Storm Bay of the north-east of the island at depths of 30-60 metres.
IMAS marine ecologist Ashlee Bastiaansen said the team used an autonomous underwater vehicle from the University of Sydney’s Australian Centre for Field Robotics to explore the seabed and reveal its biodiversity.
“The imagery we captured has given us an initial understanding of the seabed biodiversity across these deep offshore reefs and an inventory that provides an important baseline for tracking how that biodiversity changes over time,” she said.
“In addition to noting that seaweed cover dominates the shallower depths of these reefs and sponges, coral and other seabed animals are more prevalent below 40 meters, we observed a general decline in the overall diversity of organisms on these deep reefs between 2015 and 2020.”
IMAS Associate Professor Neville Barrett said these deep reefs were relatively inaccessible and therefore not well studied.
“Yet they host high levels of biodiversity and important commercial and recreational fishery values,” he said.
“With the increasing human pressures on coastal regions, including nutrient inputs from cities and recent offshore aquaculture developments, baseline studies like this are vital for monitoring and managing the health of deep reef ecosystems.”
