France Press agency
NOS . News••modified
Coral abundance has increased in the northern and central parts of the Great Barrier Reef in Australia. In the 36 years that the Australian Institute of Marine Sciences annually surveys the state of coral reefs, coral cover has been at an all-time high. However, researchers fear that this positive development is only due to short-term climate change.
In the southern part of the reef, coral cover has decreased slightly over the past year due to the presence of crowns of thorns. Starfish eat coral.
According to, the corals Research Report It can grow in the northern and central part due to the relatively good living conditions of corals, which are the small organisms that make up the coral during the last twelve months. For example, there were few destructive hurricanes in the area, and crowns of thorns are fewer than in previous years.
coral bleaching
Principal Detective Mike Emsley says: “Coral reefs have been shown to be strong and resilient enough to recover when there is no disturbance,” Reuters news agency said. However, he warns about the future: “Rising ocean temperatures are stressing coral reefs and could lead to widespread bleaching.”
Coral bleaching occurs when the water temperature becomes too high for the algae that live in the tissues of the coral. These plants convert sunlight into important nutrients for coral reefs. Without these nutrients, the coral tissue becomes transparent and the white limestone skeleton of the coral becomes visible.
Swipe to see the difference between healthy and bleached corals:
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Unsplash / Francisco Angara
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Environmental Protection Agency
This process is dangerous as coral can die if the algae and color are left for too long. It was the last bleaching in Walk. It was exceptional for this to happen during La Niña, a period when the oceans are usually cooler.
According to the researchers, this shows that the sea temperature is rising and that large-scale bleaching processes will become more frequent. Due to favorable conditions, the coral was able to recover quickly this time, but this does not happen every time. In 2017 and 2018, for example, large parts of the Great Barrier Reef died after bleaching.
constant danger
According to the researchers, the reef’s rapid recovery is mainly due to the Acropora corals. This species grows rapidly and is now the most common in the Great Barrier Reef. But Acropora is also more prone to fading than other varieties.
So the search report ends with a warning. “Our forecasts for the future point to the increase and length of marine heat waves, as well as the ongoing risks from tropical cyclones and crown-of-thorns starfish outbreaks.”
The researchers describe their findings as good news for the current state of the reefs, but they fear it won’t last long.