Whale
The IWC has designated two whale sanctuaries: the Southern Ocean Whale Sanctuary, and the Indian Ocean Whale Sanctuary. The Southern Ocean whale sanctuary spans and envelopes Antarctica. The Indian Ocean whale sanctuary takes up all of the Indian Ocean south of 55°S. The IWC is a voluntary organization, with no treaty. Any nation may leave as they wish; the IWC cannot enforce any law it makes.
Hainan
Hainan island has rich bio-diversity of cetaceans and is the site of studying these in Chinese waters. Many whales such as North Pacific right whales, western gray whales, humpback whales, and blue whales (all of these are almost extinct in Chinese waters) were historically seen in the winter and spring to mate and calve. These gentle giants of the sea had been hunted heavily and were wiped out by Japanese whalers (established whaling stations on various sites on Chinese and Korean coasts including Hainan and Daya Bay). A few Bryde's whales and minke whales may still occur in the adjacent waters along with on Leizhou Peninsula and the Gulf of Tonkin. Smaller species of whale and dolphins, such as short-finned pilot whales and pantropical spotted dolphins, but most notably the endangered Chinese white dolphin. Declared sanctuary for the species extends along the coasts. These dolphins may appear among clearer waters such as vicinity to Sanya.