Swimmers scramble to move when humpback whale pod bears down on them

Humpback whales are one of the most beautiful animals on the planet. Enormous and majestic, they are next in size only to a few other species of whales. Their fascinating evolution has taken them from being creatures the size of large dogs, and similar in appearance, to the torpedo-shaped giants that we see in our oceans to, all in what the evolutionary biologists tell us is a very short period of time.

There are very few places in the world where people can enter the water and witness these incredible whales up close. In Tonga, registered guides can lead animal lovers on swims near humpbacks, under carefully supervised situations.

This guide had his group enter the water and wait near a ledge between shallow water and a deep channel. Eventually, a large female in heat barreled past, being closely pursued by seven full grown bulls, all intent on winning her permission for breeding rights. Unexpectedly, the whale pod headed straight through the shallows and nearly crashed into the two swimmers. Strict laws prohibit intentional contact with whales and people are required to remain at least 5m (15 feet) from whales, even if it means swimming away from them. Common sense also demands that people avoid being in the path of fast moving creatures that weigh up to 45,000kg (100,000 lbs).

As the first female approaches, these swimmers quickly caught on that they were in the danger zone with a female heading straight at them. The guide also realized that this was what was called a "heat run" and that there were huge males right behind her. Wisely, he predicted that his swimmers were about to find themselves right in the middle of the fast-moving pod. He yelled and directed the swimmer to his right to retreat to the shallows. They immediately flipped onto their backs and began to swim away from the whale. Just as they reached a safer area, the males came charging through. They were so intent on catching the female that they swam over coral in the shallows, almost scraping their stomachs as they went.

The swimmer with the camera had held back slightly, in the belief that he was close enough to the reef to avoid close contact. But as he looked to his left, he was surprised to see a very large bull bearing down on him. The whale also seemed to comprehend the situation. Despite raging hormones and the overpowering urge to breed with the female, it turned abruptly as it cruised directly under the cameraman. It slowly flapped it's monstrous tail with short strokes while it was under him. Remaining perfectly still, with his arms and legs tucked in, the swimmer with the camera was braced for an impact that could very possibly injure him seriously. He had no way of moving out of the way. Incredibly, the whale appeared to have adjusted its tail movements to prevent thrashing him. One gentle brush of the tail against his legs was all he felt. Once clear, the whale resumed his large tail strokes and rapidly accelerated away. He would never know how relieved the swimmer was to be shown such mercy.

The close up look at these whales gives a look at their skin that tells a story. The numerous, large scars on the whale's back are caused by scraping on coral during fights with other whales for the breeding females or during attempts to avoid such predators as orcas and large sharks.

Breeding runs, or heat runs, can involve frantic rolling and bumping in a very aggressive bid to deter other whales from a single female.

A total of eight whales swam past these astonished swimmers, all close enough to provide an unforgettable experience. Seeing humpback whales in the wild is often an emotional and life-changing encounter.