 Trees are a minor feature, with only about 10 species present.Whitetail deer, foxes, and numerous rodents are present, but The Nature Conservancy touts the butterflies of Hole in the Mountain as the most unusual and significant of its creatures.In 2017 an attempt was made by the Minnesota Zoo to reintroduce the nearly-extinct Dakota Skipper butterfly to Hole in the Mountain, from which it had disappeared in the previous decade.