Scientists Discover Giant 1,347-Square-Meter Coral in the Pacific Ocean

Renowned for its remarkable biodiversity, the Mariana archipelago is home to some rather impressive corals. Recently, researchers from the U.S. National Oceanic and Atmospheric Administration (NOAA) described a record-breaking specimen.

Record Coral

As explained in the organization’s press release, this striking formation, located near the Maug Islands, had previously been known only to locals. As part of the national coral reef monitoring program, its teams had the opportunity to study it for the first time. “It was so imposing that simply measuring it posed a challenge for our divers,” notes Thomas Oliver of NOAA.

With a total area reaching 1,347 square meters, it is the largest Porites coral (with a hard, calcareous skeleton) ever documented. At its base, it spans 62 meters in diameter, compared with 31 meters at its apex, which, by coincidence, matches the size of the European Ariane 6 rocket.

Unlike other types of corals, it does not possess clearly defined growth rings (which would allow precise age estimation). However, it is known that Porites grow by roughly one centimeter per year, suggesting that this specimen is at least 2,050 years old.

This record specimen sits at the heart of a volcanic caldera dotted with vents that release significant amounts of carbon dioxide, contributing to the acidification of the underwater environment and impacting marine life. “This contrast highlights the exceptional nature of the Maug Islands,” says Hannah Barkley, also with NOAA. “You have these dead zones near the vents, and nearby a resilient and thriving mega coral.”

Other Underwater Giants

By the end of 2024, diving in the southwestern Pacific had led to the discovery of the world’s largest coral.

Composed of a billion genetically identical polyps acting as a single organism, this colony of Pavona clavus, about 300 years old, proved larger than a blue whale: 34 meters long and 32 meters wide.

Previously, a colossal coral reef, around 20 million years old and measuring nearly half a kilometer in height, had been identified off the coast of Australia.