Environment
AMSA does its bit for coral spawning By David Sexton Originally published in Daily Cargo News Image source: iStock.com/konwarawat janhom
Oceanographers from the Australian Institute of Marine Science (AIMS) teamed up with AMSA last November to track coral spawn slicks on the Great Barrier Reef. The Cairns-based AMSA Challenger jet aircraft was used to deploy selflocating datum marker buoys with satellite-tracking technology into the sea near Darley Reef off Townsville and Hope Reef off Bowen, to help track the movement of coral spawn slicks. AMSA Principal Advisor Aviation Assets Mike Wytcherley said they took the opportunity to combine the tracking buoy drop with marine research during a recent audit flight. ‘We typically use the satellite buoys to calculate surface drift and validate search areas in search and rescue operations,’ he said. ‘The real-time GPS feeds from the buoys give us vital information and are an effective tool in determining where we search for people and vessels missing at sea.’
AIMS oceanographer Craig Steinberg said the real-time information from the buoys revealed that the slicks had floated 52 kilometres in five days.
While AMSA undertook the deployment from the air, AIMS marine biologist Dr Andrew Heyward was on the water, watching close-up.
Mr Steinberg said the on-water observations found small slicks could form and move quickly across the reef, or dissipate if the wind created whitecaps.
Dr Heyward said most coral species released buoyant egg and sperm bundles after dark, in the spectacular annual spawning event that typically occurs four to six nights in November, after the full moon.
‘We want to better understand the connectivity of reefs so we know how they can be protected,’ he said.
Dr Heyward said floating spawn slicks could contain several million coral larvae per square metre.
‘To do this we observed surface currents using these satellite buoys in order to gather this information, which is quite rare.’
‘We want to better understand the connectivity of reefs so we know how they can be protected.’ — Craig Steinberg
Working Boats April 2019
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