Ring of Bright Water (1969)
Ring of Bright Water is a British feature film starring Bill Travers and Virginia McKenna. It is a story about a Londoner and his pet otter living on the Scottish coast. The story is fictional, but is adapted from the 1960 autobiographical book of the same name by Gavin Maxwell. It featured the stars of Born Free, another movie about a close relationship between humans and a wild animal. The film has been released to VHS (1981) and to DVD (2002).
More at Wikipedia.