Hawksbill turtles are amongst the smallest of the seven species of sea turtles. They measures between 76 and 89 cm and weighs an average of 40 to 69 kg.
​As a migratory species, they have a wide range of habitats, from the open ocean to lagoons and even mangroves in estuaries. In the early stages of their lives, like other young sea turtles, they live a pelagic life, staying at sea until they mature enough to settle down.

On top of their head, Hawkbills turtles have four little square in between their eye while green turtle have two. These squares are called prefrontale scales.

​It is not often easy to spot but Hawksbill turtles forelimbs have two claws on each fin, while green turtles only display one.
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The second claw is fairly small though and hard to notice.

Hawksbill turtles are omnivorous, beside sponges, they can also feed on anemones and jellyfish,  mollusks or sea urchins. Most of these are toxic but do not make them ill, it is however believed that their meat is poisonous to humans.

​​Small reminder: Turtles do not have teeth, but a powerful jaw and a hooked beak allowing it to “tear” its prey.

Not only do we destroy the reefs they feed on, but they cannot find a quiet beach to lay their eggs anymore and many sea turtles dye eating plastic.
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It is estimated that one in two turtles has already eaten plastic, a plastic bag that floats in water can be easily identified as a jellyfish by the turtle but is a lot harder to digest...

1. Coral reefs release eggs and spermatozoa (gametes).
2. After fertilisation (meeting of a male and female gamete), a ciliated larva called planula is formed.
3. The larva will attach itself to a place favourable to its development and form a flat disc.
4. A polyp will form and then bud (each polyp secretes a hard exoskeleton, made up of calcium carbonate, as well as an internal limestone skeleton that remains in place even after the death of the animal), to give what we know today like coral. 

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The successive budding of the polyps makes it possible to continuously enlarge the coral colony which, over time, forms the reefs.

​The reefs are therefore made up of colonies of polyp corals held together by calcium carbonates. Note that polyps alone could not live and reproduce without their symbiotic relationship with zooxanthellae algae. While the algae provides the animal with the necessary nutrients, the polyp releases carbon dioxide which allows the algae to develop and also to carry out photosynthesis which will give colour to corals in particular.

The magnificent colours of the corals that we, divers, are lucky enough to admire, their shape or even their size allow them to be distinguished in particular.

Red, brown, yellow, green, blue, purple or even fluorescent ... the colour combinations of corals are infinite! Colours can often help divers distinguish one coral from another, but their shape is a better tell tail.

There are two main types of corals: Hard coral and Soft Coral​

Encrusting corals form a crust on a substrate by spreading over their surface and thus create a thin coloured layer.
This is the perfect place for christmas tree worms and encrusting shells to settle.

Growing outward and only attached to the reef from their center "trunk", Foliose corals are often compared to heads of lettuce.

Mushroom corals are fairly solitary corals. They can be found on the sand and do not attach to other corals. Made up of a single polyp, mushroom coral can reach 25 cm in diameter.

Table corals are easily recognisable thanks to their horizontal structure which gives them great stability and perfect hiding places for other animals of the Andaman Sea and a particularily appreciated nursery for butterfly fishes.

Often mistaken for eggs, pollyps ressembles bubbles during the days which deflates at night to let the polyps feed. Despite their soft appearance, bubble corals have a "stony" structure and are hence classified as hard corals.

Another nocturnal coral with fleshy appearance, the orange cup coral is indeed a hard coral. It is classified as ahermatypic, because it doesn't contribute to building the reef.
In fact it is a pretty invasive specie which spread quickly favouring on rocky walls and chasing away sponges and hydroids.
The polyps retract during the day and "blooms" at night covering the wall with beautiful yellow
"flowers". 
Next time you see them, make sure to look closely for the pretty yellow snails that feed from them. 

Cup corals are one of the most colourful hard coral specie on the Andaman Sea.

Carnation corals are soft corals that love curants, their amazing vibrant colours make them some of the favorites for underwater photographers.

Richelieu Rock is famous for the purple coloured carnation coral that covers the best dive site in Thailand.

Coral reefs have already been reduced by more than 50% and our generation might be the last one to witness one of our planet's greatest treasure before it disappear.

OUR ACTIONS now will determine if our children will see it too.
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The Smiling Seahorse is commited to ocean preservation, when you go diving, make sure to chose and eco friendly operator to reduce your ecological footprint.

(CNN) A female Zebra Shark in an Australian aquarium has astounded scientists by producing live offspring asexually, three years after being separated from her long-term mate. [...] It is only the third documented case of a vertebrate of any species switching its reproductive strategy from sexual to asexual.
The shark had earlier reproduced after mating with a male, so it was shocking that it managed to lay fertilized eggs again after so many years without any sexual intercourse.
This asexual reproduction - which exist in other animals’ reproduction like spotted eagle ray and Colombian rainbow boa - had never been seen in sharks before now. Studies are ongoing to understand this phenomenon, but some scientists believe that it might be a natural adaptation to the lack of sexual partners.

Are Zebra Sharks dangerous? 

Zebra Sharks are non-aggressive, they can be easily approached when underwater. Divers visiting the Koh Bon Pinnacle or Koh Tachai in Thailand as well as North Twin in Myanmar have a good chance to meet one of these fascinating sharks.

How to approach them without disturbing them?!
​Zebra shark are relatively easy to approach but they will run away from you if you don't do it right!
Approach them from the side, where they can see you. Dont pass on top of them or approach them from behind, if you are in their "dead angle" they will swim away.

​​About the Zebra Shark conservation

Today, Zebra Sharks are endangered: humans are the driving factor that might drive extinction in the future. Usually, inshore fisheries use them for their meat, which is either salt-dried or fresh.  The traditional Chinese delicacy also uses Zebra Sharks, particularly its fins, for making shark fin soup, a delicacy in China.

Is Zebra shark a fish?

​All sharks are cartilaginous fish (their skeleton is made of soft cartilage, not bones). These fish all fall into the group of fish called the elasmobranchs (like rays).

ZEBRA SHARK CLASSIFICATION:
LATIN NAME: Stegostoma tigrinum (fasciatum)
FAMILY: Stegostomatidae
PHYLUM: Chordata
CLASS: Chondrichthyes

1- 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. 

2- Nautilus has 90 tentacles, situated outside the shell to catch and manipulate their prey. 

3- 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 recognise light from dull, their smell is over developed and used for hunting their preys.

4- 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. 

5 – Nautiluses are true living fossils. They have been roaming the oceans for nearly 500 million years, with almost no changes in their appearance since they first evolved. Their iconic spiral shell, their way of life, and their unique biological features have remained remarkably stable throughout geological history.

To put their age into perspective, nautiluses were already thriving 265 million years before the first dinosaurs appeared. These ancient creatures have survived multiple mass extinctions that wiped out countless other species, yet they continued to glide through the oceans with their timeless spiral shells. Today, they still drift gracefully through the deep, silent witnesses of an ancient world that existed long before mammals, birds, or even most fish as we know them.

Despite their prehistoric origins, nautiluses remain surprisingly resilient. They have a long life expectancy, often living over 15 years in the wild—a remarkable lifespan for a marine invertebrate. Their slow, steady pace of life and their ability to adapt to deep, stable environments have contributed to their persistence through Earth’s most chaotic eras. Nautiluses are, in every sense, living relics of our planet’s distant past—beautiful, mysterious, and enduring.

6- A couple of nautiluses may have sex for up to 30 hours at a time... During intercourse, males often bite females on the mantle which will leave a mark on his partner’s shell.
Some male nautiluses attempt to mate with any object that that seems to have similar shape and size as an other nautilus, and this without making any difference between male or female.

The reason I wrote this blog post is because we first came across this little fellow while diving Myanmar in 2017 but I just updated this article since our last sighting was in March 2021 in the Similans and we now have a few nice photos to add to this blogpost! :)
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After some research, we found out that this weird creature is called paper nautilus or argonauts.
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We apparently encountered a female Argonaut as male are 10 times smaller (rarely passing the size of 2cm) and dont have a shell.

Little is known about these creatures but I found these few facts  interesting enough to share!

One of the male's arm serves as a penis and is snapped off his body during sex to inseminate the female. The arms then remains inside the female body.
The female then secretes the papery shell with the tips of two tentacles. She lays her eggs inside the paper shell before using it as a house for herself. 

​But the real cool fact about argonauts is their BCD (buoyancy control device).
they are the only creature known to trap air bubble from the surface.
They swim to the surface, suck in some air from small vents on the top of their (non-compartmented) shells, close the holes with a tentacle before turning upside down and pushing themselves below the surface where they reach neutral buoyancy.
​They can then swim effortlessly and weightless!

Have you ever encountered weirder octopus?

​       Although they are small, they have developed some very industrious techniques to protect themselves. Many nudibranchs display bright colours for a multitude of reasons. Some practice what’s called aposematism which is colouration to suggest to predators that they aren’t tasty or can be toxic. This is a technique used by the Phylidiidae family that we often see in the Indo-Pacific.