This is the mesmerising moment bottlenose dolphins are filmed swimming alongside a family of sperm whales in the North Atlantic Ocean.

The incredible footage was filmed off Sao Miguel Island in Portugal’s Azores archipelago in late June.

The footage was filmed during a whale-watching trip led by the Futurismo Azores Adventures tour operator.

The company wrote on Facebook on 2nd July: “These sperm whales are in the company of some bottlenose dolphins. Can you spot them?

“This tranquil family was seen in last week’s tour. It is not the first time we see this behaviour between species at all.”

Under the video, which was viewed thousands of times, Facebook user Marcos Santos asked: “Is this type of interspecies socialisation common among sperm whales and dolphins?

“I’ve seen videos between other species of cetaceans, but not between sperm whales and dolphins.

“And secondly, I would like to know if it is possible for them to understand each other. Since, in this case, both sperm whales and dolphins use clicks to communicate, amongst other things.”

The ‘Futurismo Azores Whale Watching’ page replied: “We spoke with our biologists, and they told us that it is not very common, but seeing socialisation between species happens sometimes.

“When we observe, we can see physical interaction and body language between them. It’s probably acoustic communication, as sometimes happens between people with different languages.

“Sometimes we understand what is being said to us and other times we understand very different things. However, there are no certainties and science still doesn’t have exact answers.”

The common bottlenose dolphin (Tursiops truncatus) can reach up to 13.1 feet in length, whereas the sperm whale (Physeter macrocephalus) can reach up to 68 feet in length.