A curious sperm whale interrupted an underwater video stream off the coast of Louisiana, giving researchers aboard a ship who were watching it quite the shock.

The huge whale circled an underwater robot that researchers had sent on April 15 to monitor methane bubbles and collect samples of seawater for what is known as the Nautilus Live expedition, which aims to explore the ocean floor off the coast of Louisiana, according to a USA Today report.

Using a remotely operated vehicle called Hercules, researchers spotted a large gray object on the video monitors, with one person being heard saying, “The heck is that?”

Minutes later, the crew realizes that they are watching a sperm whale, which initially caused some concerns that it would damage the 11-foot-long vehicle or come in contact with its cables, but the whale managed to avoid bumping it, said Susan Poulton, a Nautilus Live spokeswoman, according to the report.

Poulton said the whale swam for 15 minutes around the vehicle and was eye-to-eye with the robot at one point, but never touched it. It’s the first time the crew has come in contact with a sperm whale, she said.

The Nautilus will continue to stream footage from the ship and the deep ocean dives for the next six months, with the first two months examining the impact of the BP Gulf of Mexico oil spill and then spending the next few months examining a potential shipwreck site before heading to the Galapagos islands.

Sperm whales are the largest of the toothed whales and the large predator with teeth. They are typically 52 feet in length when fully grown, but some specimens have been recorded at 67 feet long. The whale is known for feeding on squid, including the giant squid, and it can dive more than 7,000 feet in its hunt for prey, making it the second deepest diving mammal, second only to the Cuvier’s beaked whale.