What an amazing trip with this group of 16 French divers all super fun to have around!

After the rainy week we had last trip, it was a amazing having perfect conditions, both below and above water! Flat sea, warm water, excellent visibility and almost no rain.

We started this trip from Ranong and were diving around Surin island on the first day. We had some current and could drift gently surrounded by thousands of fishes ! Some even managed to find the colourful Pikachu Nudibranchia!

The second day was around Koh Tachai and Koh Bon, we love both pinnacles that were full of life!
We continued down South for the third day around the Similans Island and their beautiful granite boulder formations. The star here was a Yellow Warty frogfish (quite rare around here) but the magnificent ribbon eels at Elephant Head Rock was a close second!

Because of the rough condition last week, this trip saw the very first Blackwater Dive of the season and it was also a first for all our dear guests.

Time to cruise back north, with the morning dives in the north of the Similan islands, then two more at Koh Bon, not far from which our guests asked for a second Blackwater Dive! Your wish is my command :) We just love making you happy!

In Koh Tachai pinnacle we swam in the middle of a huge school of barracuda, than with an enormous green turtle followed by a black tip reef shark.

Last dive site but not the least, the famous Richelieu Rock in its purple soft coral costume, thousands of jack fishes hunted around to feed on the cloud of glassfish.
We were happy to find the usual suspect: seahorse, ghost pipe fish and another ribbon eel hidden under the blanket made from the millions of glass fish.

We also welcomed back a dear friend and fantastic dive guide: Julien, who’s finally back after 2 years of adventurous trip sailing on the Atlantic Ocean who is just as delighted to be back in The Smiling Seahorse Family!

Congratulations to Roro and David for your 100’ dives and Stephanie for your 300’ !

Thanks again to Subaqua Chartres Club for joining us on this amazing trip. We are looking forward to diving with you again very soon!

Part of the group decided to continue in Khao Sok National park so we organised for them a little adventure!  They even spent a night in a hammock with integrated mosquito net on a remote island of the lake from where they could spot interesting wildlife! Thanks for sharing these lovely photos!

The air we breathe everyday is as a gas made of 21% oxygen, 78 nitrogen and 1% other gas.
Nitrox, also called enriched air, is a mix of the same gaz but in a different proportion, we enrich the air with extra oxygen so the oxygen proportion is bigger. Its name: Nitrox comes from the combination of Nitrogen and Oxygen.
We refer to Nitrox according to its oxygen percentage, for example a Nitrox 32 contains 32% oxygen and is the most commonly used.

It is generally believed that Nitrox is used for very deep dives, but the reality is that it is a gas allowing longer diving time in mid-deep waters, perfect for recreational dives between 20 and 30 meters deep.
The only thing you need to know to dive using Nitrox is that beyond a specific depth, the oxygen becomes toxic. Nitrox being rich in oxygen, it becomes dangerously toxic, faster (less deep) than normal air.
But don’t get scared, after your course, you will know very well what will be your maximum depth on any given nitrox mix and plan your dive accordingly to stay safe!

Yes! Because of the danger associated with diving nitrox, which are different from the dangers of diving with air (which you have learned during your open water course), you will need to learn a few more things to dive safely with Nitrox.
The Nitrox course is the most taught speciality in the diving industry, not only it is the easiest and quickest diving course, it can be done without even getting wet.
On the MV Smiling Seahorse, we teach Padi Enriched Air Nitrox for 6000 THB. It can be easily done onboard in a few hours but can also be done online before coming through PADI e-learning. Don’t hesitate to get in touch if you have any questions!

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.

Whale sharks are the biggest fish in the oceans, their size implies slow growth rates and great longevity. Male Whale sharks reach sexual maturity in around 30 years (their adult size is rarely bigger than 8 meters). Females get much bigger but it takes them 50 years to be ready to conceive. 

While they could live up to 100 or 150 years old and mother a few hundreds pups, this late development implies slower potential population renewal as most whale sharks will not live long enough to have a descendant. 
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They have to steer clear of a lot of threats such as fishing nets...before they get a chance to breed.

Whale sharks are ovoviviparous and this is known thanks to a single pregnant female caught in nets in 1995 (nicknamed "big Mamma" ) containing 300 embryos in her utero at various stages of development. Some were still in their eggs, others already hatched, the biggest was 64 cm long.

Where whale sharks go to give birth is still a mystery, it is believed that whale sharks are born between 40 – 70cm but surprisingly no diver has ever seen a whale shark under 2m longs and it is still unknown where they spend their time before reaching this size. 

​As it is one of the few places they can still hide in… it is believed that baby whale sharks are born in very deep water and spend the first years of their lives at depth.

Watch a baby whale shark swimming off in this video:

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.