Parts of Australia’s Great Barrier Reef have suffered the highest coral mortality ever recorded and scientists fear the rest of the ecosystem could suffer the same fate, it was announced on Tuesday.
A study by the Australian Institute of Marine Sciences carried out on 12 reefs reveals a mortality up to 72%due to massive bleaching during the summer and the impact of two cyclones.
In one area of the northern Great Barrier Reef, around a third of hard corals died, marking the “largest annual decline” since the Government began monitoring the phenomenon 39 years ago.
The Great Barrier Reef, which extends 2,300 kilometers along the coast of the state of Queensland (northeast Australia), is considered the largest living structure in the world. It is home to extremely rich biodiversity, with more than 600 species of coral and 1,625 species of fish.
But several episodes of mass bleaching have turned what were once thriving beds of multicolored coral into pale, sickly expanses.
The phenomenon of coral death, which causes bleaching, is caused by the increase in water temperature, which causes the expulsion of the symbiotic algae that give it its bright color. If high temperatures persist, the coral turns white and dies.
In eight years, five episodes of mass bleaching have been recorded on the Great Barrier Reef..
The study also indicates that a fast-growing coral, acropora, suffered the highest mortality rate.
The head of oceans at the non-governmental organization World Wildlife Fund – Australia, Richard Leck, said the latest data confirms the “worst fears”.
“The Great Barrier Reef can recover, but its resilience has limits,” he said. “They can’t hit her repeatedly like this. “We are rapidly approaching a critical point,” he warned.
Leck emphasized that the area studied is “relatively small” and said he feared “similar levels of mortality” across the Great Barrier Reef.
On October 30, the United Nations, scientists and governments issued an urgent call for increased funding to protect endangered coral reefs.
Research conducted this year shows that 77% of the world’s coral reefs are affected by the fourth global mass bleaching event, the largest on record, and it is having an impact in both hemispheres.
Coral reefs are vital ecosystems that support more than 25% of marine life and almost one billion people, many of whom depend on reefs for food security, coastal protection and livelihoods.
HE The first mass laundering occurred in 1998, the second between 2011 and 2013 and the third in 2016.said Kenyan marine ecologist David Obura.
Source: Observadora
