Algae protrudes from coral show The Great Barrier Reef is 'violently' dying
Coral bleaching is reportedly more severe than ever predicted and estimates suggest it would take billions of dollars to save the Great Barrier Reef from its effects.
Brett Lewis from the Queensland University of Technology has used a time-lapse camera to capture how the well-known marine ecosystem is diminishing rapidly through coral bleaching.
Although scientists have known for some time bleaching is caused by environmental stresses - such as pollution and rising temperatures - the time lapse provides first ever video evidence of it.
Mr Lewis and his team created a setting similar to what is currently occurring in the environment, the QUT study stated.
They filled a 10-litre aquarium system with H. actiniformis coral - believed to be resilient to bleaching - and Symbiodinium algae and observed the response to rising temperatures.
Next, the team increased the temperature inside the tank from 26C to 32C over 12 hours, for eight days.
“This resilience could be due to the rapid expulsion of the coral’s algal symbionts during thermal stress, and could very well increase H. actiniformis’s chance of survival during abnormally high sea temperatures," Mr Lewis stated.
The university researchers used a microscope, digital camera and smart tablet to record coral species’ movements.
In the video, green plumes rise from the coral as it pulsates and inflates in an attempt to expel the damaging symbiotic algae - bacteria responsible for its colourful pigmentation.
"What's really interesting is just how quickly and violently the coral forcefully evicted its resident symbionts," Mr Lewis said.
It is this tiny, flamboyant algae that lives inside a coral's tissue that lives and doesn't return any invaluable nutrients, ultimately killing it.
Mr Lewis said while the coral may have expelled the algae, unless water temperatures stabilise, this coral, along with many other species will die.
“Mass coral bleaching events are a concern for scientists globally with recent events on the Great Barrier Reef highlighting the threat of elevated water temperatures to the heath of reef ecosystems," Mr Lewis said.
H. actiniformis is a solitary species of mushroom coral that can range in colour from a dark brown or velvety green, to an iridescent yellow, pink or purple.
The Great Barrier Reef stretches over 2,300 km and is believed to be one of the richest marine ecosystems in the world.
Bleaching has affected 90 per cent of the reef and killed over one-third of its coral in some regions.
More than AU$8 billion is needed to save the Great Barrier Reef, according to a report by the Queensland's Water Science Taskforce.
The Australian government will reportedly fund about AU$40 million to the Reef Trust to address threats.
News break – August 17
