Solitary male when not mating...
The Andaman see is home to many cephalopods such as octopus, squid and cuttlefish... If you come dive with us it's pretty much a guaranteed sighting!
Big reef octopus, (Octopus cyanea) a diurne specie with an amazing camouflage ability.
Theses 2 pictures were taken only few seconds apart. The Octopus can change not only it's color but also it's skin texture in the blink of an eye!
During the mating season you can have a chance to see more than one at a time, otherwise it's a rather solitary specie.
Mating season for cuttlefish (Sepia pharaonis) is from November to January, and it's very frequent to witness some kinky business while diving :)
Often seen in pairs, they are actually 3 or even 4 when mating...
While their best way to defend themselves is to blend in, they can also spray a cloud of ink to surprise it's predator and escape...
Solitary male when not mating...
The pygmy squid, (Idiosepius paradoxus) hard to see due to its micro size (about 5mm) lives on coral reef and are to be seen at night, hanging on corals or floating away with the current.
The pelagic kind of squid , hanging in mid water. They can team up in order to hunt cooperatively, using active communication!
Always in group from small to big schools, they are an easy catch for the local fishermen, still using the lamparo that attract them close to the surface...
In this article I wanted to present the various rays you can encounter in the Andaman sea. Most of the pictures below were taken in the Mergui Archipelago located off the coast of Myanmar and some in Surin and Similan islands in Thailand.
We can see 2 different kind of rays, the first kind are resident: they stay most of their time laying on the sea floor such as the stingrays, then the second kind are pelagic: they swim mid water from the depth all the way to the surface and travel long distances such as eagle rays and Manta rays!
Khul's stingray or blue spotted stingray (Neotrygon kuhlii) lying on the bottom...small size up to 50cm diameter it lives near the surface but can go at greater depth up to 90m.
Kuhl's Stingray hiding in the sand...
Blotched fantail stingray (Taeniura meyeni), laying on the sea bed, hunting at night.
can be found from 5m to 60m in small group or alone.
Not shy at all, they can get big!!! from 50cm to 200cm
Jenkins whip ray (Himantura jenkinsii) laying on the sea bed, preferably sandy bottoms, can also be found in small groups or alone at the same depth range as the marble rays. Their size can go up to 150cm.
A lot less common, the porcupine stingray (Urogymnus asperrimus) a rather solitary specie, lives at the depth of 30m on sandy, coral and sea grass bottoms Round shape up to 150cm diameter.
Cow nose eagle ray (Rhinoptera bonasus) spending most of the time swimming alone, they can be found in large groups. Often with cobia and remora.
Wing span up to 240cm they live anywhere between the surface and 110m deep.
Remora getting a free ride...
The Giant oceanic manta ray (Manta birostris) is the largest type of ray in the world and can travel across oceans. It can grow up to 7m across and weight up to 1,350kg and can live up to 50 years! A lot bigger than the more common " reef mantas" which are often encountered in Maldives and Indonesia for example.
They are filter feeders and consume large quantities of zooplankton.
Can be seen easily from the surface, as they spend day time within the 0 to 30m depth area. They are usually not shy and hang around feeding station, or cleaning stations.
In small to large group (up to 50 individuals) they are playful with one another.
Breaching the surface to get rid of parasite is not a rare sight.
Apart from humans, who are the most ferocious predator, they can be attacked by sharks, leaving some nasty bites marks!
"Black Rock" in the Mergui Archipelago, is a pretty famous dive site where we have spotted up to 50 mantas at once. It has been established by Andrea Mashall, the queen of Mantas that Black Rock may very well be the mating station where you could see the biggest All oceanic mantas gathering in the world !
Nautilus is a cephalopod and a nearby relative of octopuses and squids. This creature can be found in the tropical waters of Indian and Pacific seas, close to the coral reefs, near depth areas of 300 to 600 meters. Nautilus are (like most marine species these days) affected by overfishing and by the fact that their beautiful shells are sold as ornaments.
Some Fascinating Nautilus Facts:
Nautilus measure 20 to 25cm in average. Its shell is white to orange with brown zebra stripes. Internal side of the shell is pearly white.
The Nautilus' shell is made of isolated chambers, Nautilus are born with 4 chambers and build new chambers through time. Grown-up nautilus have more than 30 chambers. The creature (looking like a little octopus) lives in the newest chamber, which is also the biggest. The other chambers are filled with air and water to control buoyancy. A tube called the siphuncle goes through each chamber and is used to pass liquid and gas from one chamber to the other. The gas is initially diluted in liquid in one chamber and bubbles out when released in a second low pressure chamber. Just like opening a can of soda..
Nautilus moves by jet-propulsion by blowing out water through a siphon. Position of the siphon decides the direction of the nautilus: front, back, upward or descending.
Nautilus has 90 tentacles, situated outside the shell to catch and manipulate their prey.
Nautilus has a beak which cuts their food (crabs, shrimps and fish), just like other members of the octopus family.
But unlike other members of the family, nautilus has poor visual perception. Eyes can only recognize light from dull, their smell is over developed and used for hunting their preys.
Nautilus spends their day at depths and moves toward the shallow water to hunt when the sun goes down.
Nautiluses mate only once a year. 75% of nautilus caught to be studied are male and only 25% are females. Researchers don't really know why.
Nautiluses are living fossils. They have been living on planet earth for the last 500 million years with no adjustments in their appearance. Nautiluses occupied the Earth 265 million years before dinosaurs showed up.
Nautilus has a long life expectancy. It can survive over 15 years in nature.
Camille and Franck are the owners of The Smiling Seahorse, a dive company operating MV Thai Sea on the Adaman Sea.
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