The Great Barrier Reef, which stretches 2,300 kilometers off the northeastern coast of Australia, has lost more than half of its corals since 1995 as a result of warming waters caused by climate change, according to a study published this Wednesday (14.10.2020).
Coral declines (small, medium and large) occurred in both shallow and deep waters throughout the Great Barrier Reef, which is home to 400 types of coral, 1,500 species of fish and 4,000 varieties of mollusks.
Corals with deer antlers and flats, which make up important structures for fish and other species that inhabit the reefs, are the most affected according to this study that measured the size of the coral colonies in this area declared a World Heritage Site .
The co-author of this study, Terry Hughes, an expert at the Center of Excellence for the Study of Coral Reefs (CoralCoE), said in a statement from the institution that the aforementioned types of coral were “the most affected by the record temperatures that triggered mass laundering in 2016 and 2017 “.
To the two consecutive coral bleaches that mainly damaged the northern and central areas of the Great Barrier Reef, another one was added at the beginning of the year that affected the southern sector of this coral system to a greater extent, which with its 344,400 square kilometers is the largest in world.
The main cause of this phenomenon is the increase in sea temperature, which causes the corals to expel zooxanthallae, microscopic algae that provide them with oxygen and a portion of the organic compounds that they produce through photosynthesis.
In total, the Great Barrier Reef has been affected by five massive whiteouts caused by the increase in the planet’s temperature due to climate change between 1998 and 2017, in addition to another two by the influx of fresh water, according to the government Australian Institute of Marine Sciences .
“We used to think that the Great Barrier Reef is protected because of its sheer size, but our results show that even the largest and relatively well-protected reef system in the world is increasingly exposed and in decline,” Hughes reflected.
The Australian Marine Park Authority, whose government promotes coal and gas as cornerstones of its economy, last year downgraded the health status of this ecosystem from “poor” to “very poor”, noting that Goals to improve water quality of the government plan, which runs until 2050, have not been met.