Buckfast Butterflies & Dartmoor Otter Sanctuary Buckfast Butterflies and Dartmoor Otter Sanctuary offers a great, enjoyable, educational experience. Wander around the butterfly farm and see new butterflies emerge in tropical surroundings. See the otters swimming underwater in a specially built glass enclosure. Follow the otter keeper around at feeding times. Learn about the otter, its recreational and family life whatever the weather.