A team of scientists at Lancaster University (UK) conducted a study on the impact of mass coral bleaching on the survival of 38 butterfly fish species.
The increase in coral bleaching due to the effects of climate change has led to a loss of food for many fish species, especially species such as butterflyfish, which depend on coral for food.
This causes them to engage in “unnecessary wars” for corals, draining their precious energy and potentially threatening their survival.
Great Barrier Reef off the coast of Australia. Photo: AFP.
With the future of the world’s coral reefs increasingly uncertain due to climate change, a team of scientists at Lancaster University (UK) has conducted research on the impact of mass coral bleaching on the survival of 38 butterfly fish species.
According to marine ecologist Sally Keith, lead author of the study, the butterflyfish that live around coral reefs are first affected by this fish eating coral, so coral bleaching is proportional to the amount of food lost by this colorful fish.
This fact has pushed many butterflyfish species into competition for coral reefs.
The team of scientists compared butterflyfish behavior at 17 reefs off Japan, the Philippines, Indonesia and Christmas Island (Australia) before and after the worst coral bleaching event in history in 2016.
Coral bleaching affects especially Acropora corals, the main food source of butterflyfish, causing different butterflyfish species to compete more and more for other corals.
When a butterflyfish wants to signal to a competitor that a particular piece of coral is theirs, it will lower its nose and raise its spiny dorsal fin.
If this fails, they will chase each other until one gives up.
The team observed 3,700 “flashes” between butterflyfish species.
Prior to coral bleaching, different butterflyfish species were able to resolve disputes using cues about 28% of the time.
However, this ratio dropped to just 10% after the above event, indicating many “unnecessary confrontations.”
Expert Keith notes that “making the wrong decisions (of butterflyfish) about what to fight and where to invest their truly precious energy can silently bring the butterflyfishes to the brink of real famine.”
It is not clear whether the fish can adapt quickly enough to the changes caused by coral bleaching, the researchers caution.
According to Ms. Keith, this situation can have a knock-on effect between species and the food chain.
Human-caused climate change has accelerated mass coral bleaching as the world’s oceans warm.
Modeling studies last year found that even if the Paris Agreement’s climate target of keeping the Earth’s temperature rise below 1.5 degrees Celsius was achieved, 99% of world’s coral reefs will not be able to recover. In case the temperature increases by 2 degrees Celsius, the above ratio will increase to 100%.
@ Zing News
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Source: Vietnam Insider