During winter season, from November to May, liveaboard "Mermaid II" navigate to the south of Thailand. It covers Similan Island, Surin, Richelieu Rock, Phi Phi Island, Hin Daeng and Hin Muang. Similan Island is a National Park which offers 25 to 30 different dive sites to scuba divers. Wall dives with gorgonians and colorful soft corals or reef dives with variety of soft and hard coral, an incredible anemone garden are to be expected as well. The area is teemed with tropical fishes and pelagic such as manta rays, leopard sharks, barracudas and eagle rays. It is also possible to spot Whale shark during its winter season. Hin Daeng and Hin Muang are two rocks of vertical walls covered by soft and hard corals, gorgonians and anemones. The underwater life are abundant. Hin Daeng is also the only site where grey reef sharks are guaranteed to be seen frequently. Various big fish species such as sharks, manta rays, giant groupers and other species as well as sightings of whale sharks and bull sharks. Apart from the "Big", the "small" are spectacular, to name a few, seahorse, ghostpipe fish, frog fish, leaf fish, stargazer, different types of nudibranch and stone fish etc. are often seen in the area.