While critically endangered, The Hawksbill Turtles are the most frequently encountered turtles on our cruises, today let's learn about hawk-billed turtle or Eretmochelys imbricata...
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All Sea Turtles, are cold-blooded creatures, belonging to the reptile family, just like snakes, crocodiles or dinosaurs!

Hawk-billed turtle, the only representative of the genus Eretmochelys, lives in the subtropical waters of the Atlantic Ocean, the Indian Ocean and the Pacific Ocean. It is therefore quite possible to cross it in the Andaman Sea, in the midst of coral reefs. In Thailand, they can be seen both in the North Andaman (Surin and Similan islands) and South Andaman. 

Hawksbill turtles and green turtles, are both commonly seen in the Andaman Sea and hard to tell them apart at first sight. Here are a few tips to differentiate them:

Hawksbill turtles have a beak, while green turtles have a round face. 

The turtle's nose is also a good differentiation factor: those of Hawksbills looks upward, on top of their beak while green turtle's nose is forward, on the front of their face. When looking at a tutle from the front you would see the green's nostrils a lot more.

The carapace of the sea turtles are also a good way to tell them appart. The shape of the green turtle is rounder with squales next to each other and a soft edge, while the hawksbill turtle is more hear-shaped with squales overlapping each other and the edge is serrated, like a saw.

If you have a photo of a turtle from bellow and you are trying to find out if it is a green or a Hawkbill turtle, the shape will be your best friend.
The Hawksbill turtle has a longer neck, and serrated carapace (looks closely in between the two back flipper) you may also see its beak!

The hawksbill turtle is one of the few animals known to feed on sponges and is the only known spongivorous reptile. This diet make them very important to avoid sponges overtaking the reef.

Like most sea turtles, Hawksbill live a solitary life meeting only for reproduction. This turtle mates and returns to the beach where it was born, every two or three years, to lay eggs...

The hawksbill turtle digs a hole in the sand at night where it lays more than a hundred eggs.  
After about two months, these eggs will hatch. The little ones will then have to try to get back to the ocean quickly, at they risk of being eaten by birds or crabs!
Did you know? The temperature of the nest during the 60 days incubation will determine the sex of the litter! Cooler sand leads to more males hatching and vice versa.

Yes ! The hawk-billed turtle is now critically endangered. They are believed to be the most endangered of the seven species of sea turtle, with only approximately 8,000 nesting females left globally. Its beautiful carapace has been used by jewellers and for home decoration for thousands of years. Ghost fishing, by catch and sea trash are also a major treat to these gorgeous animals.

It is estimated that millions of hawksbill turtles died in the 20th century due to carapace trade. Additionally, hawk-billed turtle eggs are still eaten across the globe, and turtles themselves are killed for their flesh.

Colourful fishes have always been a favorite to tropical sea divers but have you taken a closer look at the gorgeous coral species that inhabit the Andaman Sea?  
Do you know what corals are? How coral grows to form the coral reefs (Planet earth largest living structures)  and why they are so important for our planet?
Contrary to common beliefs, corals are animals, not plants and surely neither rocks!
What you see above is actually a group of animal living under the same roof... developing over time like any living thing.

There are hundreds of species of corals! Most live in tropical seas with optimal conditions for their development: lots of light and a temperature between 25 and 30 ° C.

Hard coral are made of a rigid calcium carbonate (polyps' exoskeleton made out of limestone) and appear very much like rocks. When a polyp dies, their skeleton remains and new polyps grown on top of the last ones enlarging the coral one life at a time. Hence hard coral grows very slowly.
There are several categories of hard corals encountered in the Andaman Sea, each of these with many sub-categories and species.

With a very slow growth (from 0.5 to 4.5 cm / year), these round-shaped corals bummies constitute "the pillars" of most reefs, in the Andaman Sea and beyond! They can reach massive sizes like the multi million years bummies depicted bellow from the Burma Banks.

Soft corals are easiest identified from hard coral because they do not have a hard skeleton. They also have 8 arms per polyp. 

The Andaman Sea was gifted with several types of seafans, tall web-like fan structures in various colours. The most impressive is probably the Giant seafans (Anella mollis) which can reach 2 meters in diameter!

Not only are coral stunningly beautiful and giving the Andaman Sea its colours but they are so much more important than for background imagery! 
1- coral feed small critters and fish that feed the bigger ones, no coral= no more fish!
2- 500 million people make a living from coral reefs: from fisheries to tourism
3- coral reefs can reduce waves by 95% and could save the coastline from the damaging effects of tsunamis and storms
4- Coral reefs are also the lung of our planet! Generating half of our planet's oxygen and absorbing about a third of the carbon dioxide generated from fossil fuels usage.

The most common confusion among divers concerns the Leopard Shark, very often confused with the Zebra Shark, which is frequently encountered when diving in tropical areas.

Both species have the particularity, in adulthood, of sporting a spotted coat like the African leopard.
However, the two species are biologically different and very easily differentiable.
 
On the left, the Zebra Shark is born with "zebra lines" which change into leopard-like-spots when they reach adulthood. Their Cylindrical body measure from 50cm at birth to 3.50 m when fully grown with prominent ridges along the flanks. Upped lobe of the caudal fin is very long.
 
On the right, the Leopard Shark has a unique spotted gray-dress an can measure up to 1.80m, so it is a bit smaller than its congener the Zebra Shark. It lives in the cold to temperate waters bordering the United States, from the Gulf of Mexico to Oregon. Its favorite areas of evolution are the turbid, shallow and rough areas of the seaside, the sandy bottoms and the rocky substrates of the kelp forests.
This lovely little shark is probably the reason why American divers call Stegostoma tigrinum "zebra shark" but the rest of the world (diving warmer water and hence never in touch with the triakis semifasciata) just call them "Leopard shark"...

So what does Zebra Shark (or false leopard shark) look like when they are younger?
Rarely photographed in the wild, Zebra sharks look black with white zebra marking at birth and develop their "leopard" patterns after a few weeks.

The Zebra Shark can be found in the shallow waters all around the Indian Ocean and West Pacific from South Africa to the Red Sea, from India to North Australia and from china to New Caledonia and Southern Japan. They usually hang out on sandy batches near coral reef where they can find their food.

The Zebra Shark is known for its foraging habits; it feeds and moves mostly at night, foraging for crabs, sea urchins, small fish, snails, and other invertebrates hiding in holes and crevices. They have great whisker-like organs (barbels, in front of their snout, helping them seek out their prey). They are also equipped with smallmouth and strong gill muscles to snatch up prey but are not as strong as active fish hunter as many other sharks. They prefer to rest on the ocean floor during the daytime, where they can breathe and pump water through their gills while remaining motionless. When there are strong water currents, they might seem to be surfing as they adjust their fins to stay motionless in the open water.

Stegostoma tigrinum usually live a solitary life and only seek each other during the mating seasons. During courtship, the male Zebra Shark will follow the female, bite vigorously at her pectoral fin and tails, with occasions where he holds her fins down. These usually happen at the bottom, and a long time before, the male curls its body around the female’s and joins his claspers with her cloaca. The mating usually lasts about five minutes. Females lay about four eggs at a time, but some studies show they can lay up to 46 eggs over 112 days. The egg cases are usually between brown and dark purple, with fine hairs around, helping them stay anchored or secured when developing. Eggs may hatch in between four to six months.

We hope you liked this blogpost and found the information you were looking for. Check out our Marine life section for more fun facts about Andaman Sea life! 
​What else do you know about leopard sharks? share in the comment section below!

Nautilus is a cephalopod, 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 over-fishing and by the fact that their beautiful shells are sold as ornaments. 

​Our most recent trip took place from April 9th to 11th; we departed Ranong in the evening 9th to wake up in Surin National park, ready for 3 full day of diving, 4 in the Surin islands, followed the next day by 2 dives on Koh Bon and 2 dives on Koh Tachai and ending with 3 dives on Richelieu Rock the following days. 

​On this trip, we had 2 advanced open water students and a majority of young divers, many who experienced night diving for the first time during this trip. We are happy to report they both graduated with honors and everyone loved night diving!

When jumping in the water on the morning of our very first dive of the trip, our first group spotted a turtle swimming at a very shallow depth of 3 to 4 meters and decided to follow it for a little while. It proved to be a great idea as behind the turtle, they discovered 3 black tip reef sharks circling around the reef. Later on during the same dive, another group spotted an eagle ray passing by. What a fantastic way to start our journey!

​During the rest of the day, Surin made for incredibly lovely dives, with some coral dives mixed with a drift and muck dive, all the group saw blue spotted sting rays sleeping in the sand, some cuttlefish were spotted, a juvenile pipefish, and even a hump head parrot fish!!

​The following day, we sailed to koh Bon for 2 morning dives. The visibility was great and currents allowed us to do 2 dives on the pinnacle. Some of us chose to dive the West ridge and got to hang out with one of the resident octopuses, saw lots of shrimps, nudibranches, while others dropped on the pinnacle, traversed to west ridge and spotted a black tip reef shark. 

​While Koh Bon had only mild to no current, koh Tachai had stronger currents bringing in a plethora of barracudas, jacks and the usual schooling batfish. On our sunset dive, we sought shelter from the current and began our search for small creatures and found plenty of nudibranchs, lobsters, box fish, baby scorpionfish and more. 

In the evening, we feasted on our usual Barbecue, and played a really fun game called the box game. We’ll let you figure out the rules for yourself, photos are better than words sometimes! With all the young and flexible guests onboard, it made for a lot of laughs and good vibes. The cocktails might have also helped. 

​On our last day, we dove 3 times on Richelieu Rock before setting back to Ranong. On top of the usual harlequin shrimps, ghost pipe fish, frog fish, tiger eye coweries, we were lucky to spot another eagle ray, who came to see us off until next time.  No Whaleshark this time, but we are keeping our fingers crossed for the next time.

​Thanks everyone for making this trip a great one, and hope to see you back onboard soon and again, congrats to our new AOW!

Another special trip onboard MV Smiling Seahorse; On the agenda, a total of 15 dives: 10 dives on Richelieu rock, 2 on Koh Bon, 1 on Koh Tachai and 2 amazing black water dives!

In Richelieu Rock it is always a difficult to select what lense to use for a dive as the marine life is so diverse from the smallest to the biggest critters, we alternated wide angle and macro lenses to capture the best of Richelieu Rock; our regular underwater friends the harlequin shrimp (we even saw a few cute little babies this time), the giant frog fish (yay, he is back after hiding so well on our last visit), the ghost pipe fish (2 pairs), the baby seahorse (as well as an adult yellow tiger tail seahorse) were all dashing and ready to pose for our cameras. We also saw so many cowries, they seem to be in season at the moment!

The visibility was a good allowing 30m of crystal clarity on most dives which paved the way for glorious encounters with a few tornados of jacks and schools of barracudas to please the videographers. One group of lucky divers even spent a nice moment with a passing eagle ray!

Our 8th dive of the trip on March 11th was something completely new to us and to many of our divers: a blackwater dive. Due to logistics, we split the groups in 2 and organized 2 back-to-back dives for an intimate group of 10. The principle for this is to set up a floating line in the blue with multiple lights attached to it, that attract plankton which in turn attract small fish, which potentially attract bigger fish. Depth for the dive was capped at 18 meters, and we ran approximately 45 minutes dive in the dark, in awe face to the plankton, larvaes, squids and jellyfish. 

On Friday, we headed towards Koh Bon where we dove the coral-covered pinnacle. We love it for the mystical feeling it gives us knowing that there are always chances of a glimpse at something big! One group enjoyed a beautiful eagle ray at depth, while the others discovered a cool stone fish hiding on the top. Dive 2 and 3 saw us diving koh Tachai, where the usual school of barracudas was hanging out in the blue, as well as the trigger fish and the sweet lips. One group even lucked out by sighting a leopard shark! 

At night, we were all ready for our second black water dive! We inverted groups and those who jumped in first the previous night jumped in second this time and off we went for an incredible 45 minutes dive. Much to our surprise and awe, the waters were full of newly hatched baby sailfish that we felt so incredibly privileged to admire and capture on camera as well as a deep water fish rarely seen by any diver: a juvenile tripod fish, still living the pelagic life befor settling down on the deep sea floor!
There were also lots of squids, alien looking plancton shapes, jellys, baby crabs, little fish larvea, squid and even a pelagic yellow snake! It was a truly a amazing dive! Now that we have discovered blackwater diving, we are surely hooked!!

We celebrated our underwater discoveries with our customary bbq night and drinks, and sailed back to Richelieu rock for our last day.

You might know the saying "less is more"? Well, this surely didn’t apply to our last day at Richelieu rock and we would even go further and say we just can’t get enough of this dive site!!  If you want to take a cruise of a week on Richelieu Rock, we might be the right boat for you!

Highlight of the day was going back to visit the clark’s anemone nest we had seen on our last trip, and even finding a new nest this time of tomatoe anemone fish full of tinny little eye-baring eggs! A cuttlefish made an appearance and we spotted a bamboo shark resting in a crevasse. We bid farewell to all our regular buddies: the ghost pipefish, the giant frog fish, the harlequin shrimp, the school of fusiliers and can’t wait to visit them on our next trip.

See you again next Week Richelieu and to all our wonderful guests onboard this trip, we certainly look forward to have you back onboard (next week for some, soon & later for the others) !

Our Liveaboard trips
Only one month left of this "out-of-this-word season"!
Join us for an unforgettable cruise, Thailand has never offered such fantastic dives away from the crowd! Conditions are amazing with more than 30-40 m visibility, Macro life is striving and we just can't get enough!

             Today there are somewhere around 3000 documented species of these incredible molluscs that can range from a mere 4mm to a hefty 60cm. Nudibranchs are invertebrates that spend a certain stage of development with a shell. They will always shed this shell at some point before adulthood. All nudibranchs are members of the sea-slug family, however not all sea-slugs are nudibranchs.  ​

          Because they have both male and female sexual organs, a pair can inseminate each others so that you have two pregnancies instead of one. However nudis still need to find a mate. They cannot impregnate themselves!
​​       Nudibranchs are carnivorous and love to eat sponge, hydroids, algae, coral, anemones and even other nudibranchs. They can be found mostly in shallow reefs in warm salt water, but there are some species that live in deeper or cold waters and some can even survive the lower salinity of brackish water. They are found in great abundance at any of the dive sites of the Mergui Archipelago in Burma. 

            Nudibranchs have complicated names which can be very daunting to someone just starting to learn about them. They often have common names which can be easier to remember but they can also cause confusion. For example, some people call the same nudi different names depending on where they dive and what the locals refer to them as. Sometimes a distinguishing feature that led people to give it a common name is not specific to that species leading different nudis to be called the same thing. 
           Using their scientific names is the best way to accurately identify nudibranchs even if it can be a bit of a mouthful. Taxonomy is the way we classify living things in biology and it is an intricate science. Basically speaking, plants and animals are divided into family trees that get more specific as you travel downwards eventually allowing you to name individuals. ​

​           Understanding the difference between the different species is a great place to start but there are other things to consider when identifying a special slug you found on the reef. Looking at its body shape can be very helpful as well as colouration and any markings like stripes or polka dots. Also when in doubt there are many resources available to you like marine species identification books or public forums on social media.
Some of my favourites are ID Please (Marine Creature Identification) and Nudibranch Central on Facebook.

Please feel free to hover your cursor over any of the photos for ID.