Yep - 140 tonnes of blue whale going at it. Of course, it's a love story with a woman at the centre and two males fighting for her attention.
The video was shot during a scientific expedition (there are two boats on the St. Lawrence licensed for this). The two whales concerned have been known to the scientists for a little while, but have never fought before. This fight behaviour has added significantly to the understanding of whales and how they interact as a group - it's probabkly the longest fight witnessed and hence provides a bit more data than any other.
The majority of the boat were scientists with two paying passengers to fund the expedition. It was led by Richard Sears who has been studying whales since the 70s and was responsible for getting blue whales onto the endangered animals list.
As you might imagine, he's about the last person who would want to see whales harrassed. Whales have a great sense of hearing. They can hear you coming about two miles away. If they don't want you around, they will clear off. They can swim at about 30 knots and dive for 20 minutes - this means that if they don't want to be around you, they can dive and be ten miles away before they re-surface - well out of sight and not really trackable. These whales were happy to have us around and showed no signs of elevated stress, i.e. no whales were harmed during the making of this video.
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