Other wildlife to be found in Doubtful Sound includes fur seals and penguins, or even large whales. Southern right whales and humpback whales are the most frequently seen especially the later. Others include minke whale, sperm whale and some giant beaked whales). Orcas (killer whales) and long-finned pilot whales can be found also. The waters of Doubtful Sound are also home to an abundance of sea creatures, including many species of fish, starfish, sea anemones, and corals. It is perhaps best known for its black coral trees which occur in unusually shallow water for what is normally a deep-water species. The sound has been identified as an Important Bird Area by BirdLife International because it is a breeding site for Fiordland penguins.