The Largest Underwater Creature Ever Found Is An Animal You Might Not Expect

The deep sea is full of strange creatures from the appropriately named goblin shark to the gulper eel, which wouldn't be out of place in an "Alien" movie. But even these bizarre ocean species might struggle to match the uniqueness of the largest underwater creature ever found. When cinematographer Manu Dan Felix and fellow members of the National Geographic Pristine Seas team first discovered this organism, they thought it was a shipwreck. But the shipwreck turned out to be alive, and it was eventually found to be a species of coral called Pavona clavus.

Yes, the largest underwater creature ever found is actually a massive coral colony. Measuring 111 feet wide, 104 feet long, and roughly 19 feet high, the mega-coral is visible from space and is longer than most blue whales ever recorded, which typically measure 80 feet in length. The coral colony is located in the southwest Pacific Ocean's Three Sisters island group, which forms part of the Solomon Islands and is a hugely important habitat for a variety of marine life. However, like so much of the world's ocean in an age where global warming is having a major impact, the Pavona clavus colony will not be immune to climate change and acts as yet another reminder of our duty to protect the world's oceans.

In October 2024, a group of more than 15 scientists and filmmakers set off on an expedition to explore the oceans surrounding the Solomon Islands as part of a program to gain a more comprehensive understanding of the ecosystem and ultimately help protect it.As part of the Coral Triangle, the Solomon Islands have long been known to host a variety of unique species including an endemic stingray, multiple species of marine turtles, and coral reefs. But none of the explorers were necessarily expecting to come across such a singular discovery — what they thought to be a huge shipwreck has now been confirmed to be the world's largest coral colony.

The group identified the impressive organism in November 2024, a month after the expedition was launched. Rather than a coral reef, which is made up of multiple coral colonies, the newly discovered Pavona clavus group is a single colony comprising almost 1 billion coral polyps. These tiny creatures are actually related to anemones and jellyfish, and while they can survive on their own, they're often found in colonies. When multiple colonies join together they become a reef, but the Pavona clavus grouping found in the Solomon Islands is remarkable for being such a large single colony.

Coral has a long lifespan, and this particular cluster is thought to be between 300 and 500 years old. It has developed a brown hue that gives it the appearance of a giant rock, but upon closer inspection, the organism is marked with yellow, blue, and red streaks and provides a fascinating insight into how organisms might survive multiple centuries and the associated environmental changes.

The colossal Pavona clavus colony isn't just remarkable for being such a gigantic example of an underwater organism. It's also home to multiple species, from young reef fish and crabs to shrimp and more. As such, preserving this incredible discovery is of the utmost importance, especially since reefs in shallower water nearby have taken the brunt of climate change and warmer seas, which have degraded these vital habitats. Since the Pavona Clavus is in deeper water, it appears to have remained relatively protected from such environmental threats, but that doesn't mean it's entirely safe.

As a 2025 study published in Marine Policy noted, just 8% of the world's oceans are protected and that while countries around the world have pledged to increase that number to 30% by 2030, a lot of work needs to be done to hit that target. With no roadmap currently in place, that's going to be a tough task, and according to the researchers, countries will need to set up 300 large and 188,000 small Marine Protection Areas to stay on-track. What's more, in 2023, the World Economic Forum claimed that the world has lost 14% of its coral reefs since 2009, naming these ecosystems as one of the most threatened on the planet. With that in mind, the discovery of this mega coral colony is a positive development that simultaneously provides hope and emphasizes the importance of ocean conservation.