1 February 2022.

Introduction:

The scientists have recently discovered a coral reef along the coast of Tahiti. The reef is two miles long and is unaffected by anthropogenic activities and climate change.

About the coral reef

• The coral reef was discovered during a dive expedition.
•  The expedition was supported by UNESCO.
• The corals discovered were six feet in diameter.
• The scientists have witnessed coral spawning in the island.

Corals found in Mesophotic zone

• The coral reefs were discovered at a depth of 100 feet to 210 feet.
•  This is a bit deeper.
• That is, the corals were found in the mesophotic zone.
• These are the deepest zones till which the sunlight can penetrate.
• This depth protects the corals from human activities.

Not affected by Coral Bleaching

• In 2019, the entire French Coral Polynesia was affected by coral bleaching.
•  The coral bleaching occurred due to climate change and global warming.
• However, this new coral reef was not affected by the 2019 coral bleaching.
• This is mainly due to its depth.

What is coral bleaching?

• The corals are marine invertebrates. They hold microscopic algae are zooxanthellae.
• The algae provides food for the corals and the corals provide accommodation to the algae.
• They are symbiotic.
•  Due to global warming and increase in sea temperature, the corals find it difficult to hold the algae.
•  They release them.
• The corals get their colours from these algae.
• When the algae is released they become colourless.
•  This is called coral bleaching.
• With this, the corals die as they do not get food.

What is Coral spawning witnessed in the reef?

• Coral spawning is a natural phenomenon.
• During coral spawning, multiple species of corals release their eggs and sperms.
• They float to the surface of the ocean, fertilise and form new larvae.
•  The synchronisation occurs after the new moon day.

Tahiti

• Tahiti is the largest island in French Polynesia.
• It is located in the central Pacific Ocean.
• Tahiti was formed by volcanic activity.
• The island accounts to around 70% of the population of French Polynesia.