Rae Gill is the tour director of our supplier WhaleSwim Adventures. They take people swimming with humpback whales in Tonga:
"Humpback whales are the most active whales. They jump out of the water - that's known as breaching - they flap their fins, flap their tails. They have to surface to breathe, as all whales do. But they're also baleen whales, which means they don't have any teeth. All baleen whales migrate because they have to go to colder waters to get their food - tiny crustaceans known as krill. So it's usually in the breeding season that the whale watching takes place for humpbacks, because that's when they migrate away from the extreme regions, like Alaska. During the breeding season they stay put for three or four months in warmer waters before making the big swim back to the Arctic or Antarctic for feeding.
Even though they're huge, humpbacks don't eat when they're in Tonga. They eat big mouthfuls of krill, and put on all this blubber in the feeding season, then go off to have babies."
Listen to the humpback whale's call: