Dolphins WWF Wall Calendar: Dolphins are mammals, not fish. They are highly social, friendly and playful, and are believed to be the most intelligent of all animals. According to an international group of experts at IUCN – The World Conservation Union, some species of dolphins are so endangered they could vanish within a decade. In the US and Canada, WWF receives 50 cents for each WWF calendar purchased.Wall Calendar12-month Calendar14" X 13"Stapled BindingMedium Square GridObserves Major Holidays