A heart warming video, thanks for posting that.
The thing I appreciated most about that incident is that it was obvious the whale realized that the people were trying to help it and it was cooperating with their efforts and not struggling against them. Those people were very brave to take such a big risk with minimal tools to work with and the possibility of their boat being capsized if the whale had panicked.
I suspect all that show the whale put on of repeatedly breaching and slapping for such a long time afterwards wasn't only out of joy and thanks for finally being free. It would have served a number of purposes - getting the blood flowing and stiff muscles working properly again after being trapped in an immobile situation, also for communicating long distance to other whales (mother? family pod?) to let them know its location and to hear their responses, also for slapping off dead skin cells and parasites. That poor whale had a number of parasites attached to it's sensitive skin that must have been a terrible irritation for it since it was unable to rid itself of the parasites until it was freed.
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