The video box describes the film as a 'delight for all ages' and the IMDb plot outline describes it as a 'family film'. I just had to find a definition of 'family film' and came across the following: "Usually consisting of comedies or adventures, these films are often based on children's literature and can involve any number of helpful animals, friendly supernatural beings and fantasy worlds, all geared to stimulate and appeal to the imagination. Whatever the situation, there is little or no offensive material and generally a lesson is learned on the way." Not an apt description of Tarka The Otter, which contains some thoroughly unpleasant scenes, totally unsuitable for young children, and an ending that qualifies the film as a 'feel bad' movie. The lesson learned? As I said: life is cruel. Family entertainment? I don't think so. Unless you hate your family, that is.
Another review, more revealing than this but worth reading, can be found by following the 'external reviews' link.