The latest unlikely stars of YouTube are two humpback whales cavorting off the coast of Bermuda.
The 45ft, 40 tonne mammals were filmed for more than two hours by local author and conservationist Andrew Stevenson, who posted 10 minutes of the underwater footage on the video-sharing website.
Despite having had little publicity, the clip has now been watched by more than 2,500 people.
And its word-of-mouth popularity is growing, with viewers from around the world leaving glowing recommendations. Mr. Stevenson, 56, told the Bermuda Sun that the footage was the end result of more than 300 hours on the water looking for the elusive whales.
Mr. Stevenson, who captured the images on a handheld digital camera, also described how he believed his life was at risk when the two whales began to fight.
He said of the encounter, 15 miles off the coast of Bermuda: "Anyone who has gone looking for whales will tell you how difficult it is to get good film footage of them. Finding them at all is difficult. Then, either they are way off in the distance, or they are closer but the visibility is poor. On this day, everything just came together.
"I was actually in the water swimming with a pod of dolphins. Suddenly their body language changed and their clicking noises changed and I looked down and there was a fully-grown male humpback whale swimming underneath me.
"I filmed him, and he watched me, for over two hours. It was the most amazing experience of my life. Sometimes he would just hang there, as if he was listening to my heartbeat, which I'm sure he was."
The YouTube clip is accompanied by whale noises, recorded by Mr. Stevenson on a separate trip, and by a piano score, played by Mr. Stevenson's wife.
At times, the whale makes human-like gestures and looks closely into the camera. A companion video - shot from the boat - shows the whale passing close to Mr. Stevenson and illustrates the enormous size of the creature.
At times, the whale came within a few inches, Mr. Stevenson said. On his YouTube post, he describes the emotional impact of the encounter. "I had the overwhelming feeling that I was looking into the eyes of an intelligent creature. It took me a week to sleep after the experience and a month to talk about the experience without becoming emotional."
The solo whale was eventually joined by another male, and the two mammals circled one another before beginning to fight.
"That was the only time I was frightened," said Mr. Stevenson. "I couldn't see anything because the water was foaming, but I could hear the huge slap of their tails on the water. That's when I thought, 'This could kill me.' I was 100 meters away from the boat and I had a heavy camera that would have acted like a projectile if it had been hit by a tail. These two huge creatures were thrashing around. But I wasn't hit. I'm sure they avoided me on purpose. And eventually the second male was driven away."
One YouTube viewer wrote on the website: "Wow, I am at peace right now just from having experienced your video."
Another wrote: "I am stunned. That's the most fantastic underwater footage I have seen of humpbacks. It's tingles down the spine stuff."
The author of eight books, Mr. Stevenson is currently compiling a documentary on the migration of humpbacks passed Bermuda.
He believes the whales use the island waters as a refueling point on their journey between the Caribbean and Canada. Mr. Stevenson is also an avid anti-whaling campaigner, and he says the YouTube footage is designed to increase awareness of the beauty of the mammals.
To see the videos, go to www.youtube.com and enter awstevenson in the search bar.
