This might be an essential species towards saving these reefs...

Coral reefs are very fragile and complex ecosystems. According to the Global Coral Reef Monitoring Network, 20% of the world’s coral reefs are already destroyed, with another 24% at high risk. This might not only be due to coral bleaching caused by human activities but another essential organism essential to coral reefs ecosystems- parrotfish.

Coral bleeching before vs. after

Parrotfish can eat off algae on these corals and excrete sand. The sand will be deposited on to the shore by tides, forming coral reef beaches. Most tropical beaches are formed with the help of parrotfish as well as other algae eating grazers such as sea urchins. However, parrotfish still serve a far more important purpose in their grazing than their excretion.

Overfishing parrotfish has many consequences due to its unique role in the ecosystem. Algal blooms have become immense threats to coral reef ecosystems. The algae can deplete oxygen for corals and steal their precious light.

The digestive systems of parrotfish helped them with gnawing algae. They will simply take all the nutrients found in the algae and excrete the leftover as sand. One important process of their digestion is to deplete calcium carbonate found in the ocean. Calcium carbonate is exactly what coral is made of. It releases a tremendous amount of CO2 when reacting with acid. CO2 concentration in the ocean will even cause even further ocean acidification. Without the intervention of parrotfish, this will eventually turn into a vicious cycle.

Strangely, these fish are especially heavy sleepers after all this work, and this means dangerously heavy for the parrotfish population. They will tuck themselves under a rock or in a ledge and use some mucus to build a translucent, semi-solid sleeping bag. However, this makes them fairly easy to catch with a net.

The report from the Global Coral Reef Monitoring Network of IUCN stated that protecting parrotfish can be viable through fisheries laws and regulations or monitoring and reinforcing these regulations.

The charisma of nature should outweigh the stakeholders and greediness, and this should be why we are saving these coral reefs.

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