A white Omura's whale has been spotted near Koh He in Phuket in an unprecedented sighting, possibly marking the first sighting of this very rare mammal in Thailand and even the world, according to Assoc Prof Thon Thamrongnawasawat, a marine biologist and lecturer at Kasetsart University.
The renowned marine biologist wrote on Facebook on Saturday that based on detailed information of the marine animal sighted on the afternoon of Jan 1 south of Koh He, it seems to be an Omura's whale, not a Bruda whale.
The most noticeable difference between the two is that an Omura's whale has a single defined ridge on the front of its head, while a Bruda whale has three, he said.
The whale was spotted with another Omura's whale about 4pm by a person travelling on a boat called Happy Ours, about 9km south of Koh He.
Assoc Prof Thon said Omura's whales are rare species primarily found in the seas in Southeast Asia and the waters south of Japan.
In Thailand, while the mammals have been sighted both in the Andaman Sea and in the Gulf of Thailand, they are more commonly sighted in the Andaman Sea.
The marine expert described a white Omura's whale as "doubly rare".
The probability of sighting one is about one in 10 million or more, he said.
Yutthapong Damsrisuk, chief of Nopparatthara-Phi Phi island park, said last week that a group of tourists recently spotted a 7-metre white whale near Phi Phi island.
The authorities were trying to verify the species.
Tour boats and fishing vessels are urged to take extra precautions when operating in areas where Omura's whales are known to be present, saying the sighting of these rare species demonstrates the diversity of the marine life in the Andaman Sea.