THE remote Kimberley coast, widely considered to be the planet’s last great tropical marine frontier, is slowly beginning to yield its secrets.
At the height of tropical cyclone Lua, which this week hammered the region with winds of up to 160km/h, marine scientist Ali McCarthy, 24, became the first person to witness the spawning of Kimberley onshore corals.
The event took place nine days after the full moon and after two wet, windy nights of monitoring aquariums at Cygnet Bay, about 200km north of Broome.
The captive spawning mirrored exactly what was happening on reefs a few hundred metres away, where the waters were awash with slicks of bright blue and pink secretions as corals released their gametes into the water for fertilisation.
The event, which can be accurately predicted, is remarkable for more than the way in which it will help explain the lifecycle of one of the world’s least understood coral regions. The Kimberley coast is recognised as the most coral diverse area in Western Australia and may rival the Red Sea with 280 species of hard coral from 55 genera, many new to science. The research will help unlock the secrets of why Kimberley corals are thriving where contemporary marine science says they should not even exist.
“The environment in which the corals exist is almost beyond the normal parameters for coral survival, let alone growth,” said Ms McCarthy.The onshore reefs of Cygnet Bay experience water temperatures of up to 40C without bleaching. They also withstand 12m tides, extreme turbidity and ocean acidification that would be devastating to other coral systems.