Fair. There is a huge debate in the comments section of the video about this, many people say it is somehow obvious that the bear was trained with 'positive reinforcement'. I don't know much about that, so i can't have a strong opinion.
The guy gives a bite of food as a reward for every trick the bear does. If somehow the bear enjoys the tricks, or even just doesn't care as long as she gets food, it's fine. It is a weird subject. We will never know what the bear thinks. E.g. , one could argue that the bear does not like at all to stay in a frozen river for hours trying to catch salmons, playing the trumpet is easier and more preferable for her ( btw, what is is the correct gender for animals in English? In Greek each one has a gender, bear is a female word, dog is male, lion is neutral ). To me it still feels like the animal is abused. But that is all intuitive. Who knows...