The renowned marine biologist wrote on Facebook on Saturday (Jan 6) that based on detailed information of the marine animal sighted on the afternoon of Jan 1 south of Koh Hei, it seems to be an Omura’s whale, not a much more common Bruda whale, reports Bangkok Post.
The whale was spotted with another Omura’s whale about 4pm by a person traveling on a boat called Happy Ours, about 9 km south of Koh Hei.
Assoc Prof Thon reminded that 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 Nopparat Thara – Ko Phi Phi Island National Park, mentioned last week that a group of tourists recently spotted a 7-meter white whale near Phi Phi island. Authorities are currently working to verify the species.
Tour boats and fishing vessels are strongly advised to take extra precautions when operating in areas where Omura’s whales are known to be present. This precaution is emphasized, underscoring that the sighting of these rare species highlights the diversity of marine life in the Andaman Sea.
Officials from relevant departments will be searching specific areas south of Phuket in hope for more encounters with the whales, Assoc Prof Thon added in a separate post on Facebook.
Of note, the most recent series of confirmed and unconfirmed Omura’s whale sightings began on Monday (Jan 1), when officials from the Mu Ko Surin National Park photographed this rare marine animal near the archipelago. The rare sighting was reported by officials on the national park’s Facebook page the following day (Jan 2).
On Saturday (Jan 6), yachting enthusiasts Christine Rehm and Frank Klose contacted The Phuket News to share their whale spotting experience one day before (Jan 5) off Hin Bida near Phi Phi Islands.
"While underway with our private sailing catamaran, it seems like we spotted two Omura’s whales (Balaenoptera omurai). Hopefully, our observation can contribute to learning more about the presence of such beautiful animals in the Andaman Sea," the couple wrote.
A happy confirmed encounter with an Omura whale in the waters of Phuket, Phang Nga and Krabi took place in late October, 2023. National park officers at the Mu Ko Surin National Park confirmed the sighting in the Surin Islands archipelago with a post online on Oct 26. The case was reported by The Phuket News.
The mysterious giants
The rare whale, that was first recognised in the wild only eight years ago, was spotted by a group of tourists on a sightseeing boat. Park officers then confirmed it was the first time that an Omura’s whale had been sighted in the area.
The Omura’s whale (Balaenoptera omurai) is similar to the Bryde’s whale (Balaenoptera edeni brydei), and is protected in Thailand, the park officers explained in the post.
They grow to 20 metres long, weighing up to 20 tonnes. Omura’s whales are found alone or in pairs, but may group together for feeding. The whales have been seen “lunge feeding” on krill and small fish.
Omura’s whales are found in tropical to warm regions, in both offshore and coastal zones. Most are found in the eastern part of the Indian Ocean and the western Pacific Ocean.
However, Omura’s whales have been confirmed as seen in Thai waters, from Prachuap Khiri Khan to Songkhla in the Gulf of Thailand, and they have been seen along the Andaman coast. A group of four have been previously photographed near the Racha islands, south of Phuket.
The Omura’s whale was first described by three Japanese scientists, Shiro Wada, Masayuki Oishi and Tadasu K. Yamada, in 2003, and named in honour of Japanese cetologist Hideo Omura, who passed away in 1993, the park officers explained.
However, Shiro et al had first recognised Omura’s whales only from dead specimens in 2003. It was not until 2015 that the first specimens were recognised alive in the wild. The International Union for Conservation of Nature (IUCN) does not even have enough data to determine whether Omura’s whales are endangered.
Omura’s whales had previously been mistaken for Bryde’s whales as both species look similar. Scientists now know that Omura’s whales are not related to the Bryde’s whale at all.
The dorsal fin of the Omura’s whale is similar to that of a Bryde’s whale, but is more curved and located more towards the tail. Also the head of an Omura’s whale has one convex ridge. Bryde’s whales have three.
The body of an Omura’s whale is a light-coloured grey-black, and they may have a whitish to pink belly. They also have 80-90 light-coloured grooves under the chin, extending past the navel.
The left side of the jaw is black, but the right side is faded or white. The jaw is filled with 180-210 pairs of short and wide teeth that are white, yellow or black.