This article is going to teach you how to differentiate the 3 most common species of  Scorpionfish we encounter in the Andaman sea: Bearded Scorpionfish, Devil Scorpionfish and Stonefish.

These three species are often mistaken because they are quite similar (indeed they belong to the same family), but below are some simple tips to tell them appart during your next dive trip.

Let’s start with their similarities:
- these members of the Scorpaenidae family live on to the ocean floor, often hiding among the coral reef and swim about as well as a chicken can fly...
- They have large heads with strong bony cheek and a surprisingly wide mouth which can capture large preys.
- They are not aggressive but their back spines are highly poisonous. They are not agressive but under attack, they expand their spines to protect themselves and quickly escape to a nearby hideout. 
- They are all sedentary prey-stalkers using the same passive strategy as a gecko. You will rarely see them moving something other than their eyes except when they are swallowing whole a prey that passed a bit too close...

A little infographic to help you differentiate visually the 3 species

 That’s it for today, let’s hope that you learned how to differentiate these 3 species and that you will observe them in our company on The Smiling Seahorse’s boat!

A very popular subject of many marine biologists, the Octopus Vulgaris or common reef octopus, is a master of disguise.
The octopus is a mollusc belonging to the class of cephalopoda.
It's arms can grow to a whopping 1m in length and its mantle as long as 25cm.

This type of octopus can be found in the tropical and temperate waters of the the Eastern Atlantic, Mediterranean sea, the Pacific ocean and the coast of Africa.
It prefers shallow rocky bottoms or coastal coral reef in depths above 200m. Octopi will find themselves a shelter where they can minimize exposure and stay safe but will come out, mostly at night, to hunt. They usually move by crawling along the sea floor where it can protect its belly. They are also known to swim using a type of jet mechanism found in its mantle cavity. 

Octopi are solitary creatures with short life spans. They spend most of their young life eating and growing until they reach sexual maturity. At this time, they will metabolize muscle mass to make sperm and eggs and search for a mate. 
Mating can be very dangerous for the male. A female doesn't often refuse a male's advances but it is not uncommon for the female to change her mind and eat the male. To address this problem, males have a specially adapted mating arm that can deliver sperm into the female's mantle cavity from a safe distance.
The female will lay between 100 000 to 500 000 eggs which she will very rarely leave unattended for her 4-5 month brooding.  She will even stop eating to take care of them and will die shortly after they hatch. 

Studies show that they are extremely clever and resourceful. They have a much more complex nervous system than other mammals and most of their 500 million neurons are found in their arms. The have been taught to navigate mazes, problem solve and recognize visual clues to find the best way to get to a reward. Don't under estimate them !

The Common reef octopus can be found in Mergui Archipelago between other cephalopods and reef creatures. Diving in Myanmar offers a large marine biodiversity, a paradise for all divers !

​FishBase http://www.fishbase.org/ a large base of worldwide fish, available in many languages
Australian Museum http://www.australian.museum/ a complete sheet with fishes classified by family and order
Gobies http://www.gobiidae.com/ a goby specialized website
Fish Photo Database http://www.fishdb.co.uk/ an English names database with pictures
​Fish Photo list http://www.oceanlight.com/ a list a fishes around the world

​Sea Slug Forum http://www.seaslugforum.net/ a database from the Australian museum
Nudibranch Identification http://www.nudipixel.net/ a facebook page about nudis
Cephalopods http://www.thecephalopodpage.org/ Catalog and articles about page
Facebook group ​NUDIBRANCHS, WORMS AND SEA SLUGS a share and ask plateform

The ribbon Eel is the only member of its genus. Scientists thought for a long time that there were 3 types of ribbon eel, the black, the blue, and the yellow species. But now we know they form a unique species changing sex and colour during its lifespan!

You can find the Ribbon eel in sandy areas around reefs and lagoons of the Indo-Pacific Ocean. It can be found in very shallow waters down to 60m.
It usually stays in the same cave for months or even years and two individuals (usually adult males) can be seen sharing the same hole.

​The ribbon eel is a carnivore which preys on small fish and other animals that swim too close to their hole. They can be generally observed poking their head out of their hole waiting to catch  prey as it wanders past.

Every individual is born as male.
Juveniles and sub-adults are black with a yellow dorsal fin. When they reach adulthood, they keep the yellow fin but the body turns blue and starts developing female reproductive organs.
​When they reach their full size, they turn into female and change their color to complete yellow.
They will then find a mate, lay their eggs, and die within a month.

It is due to their short lifespan that the female ribbon eels are rarely observed.

The ribbon is the only protandric hermaphrodite eel, meaning they are capable of changing sex to female if there is a shortage of natural females in the environment.

             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.

They are often found in pairs and if a couple successfully establishes a secure den they can be found in the same place together for long periods of time. Sometimes Harlequin Shrimps will even spend the vast majority of their 7-year lifespan in the same place and with the same mate. They will live, breed, hunt, and defend their territory together loyally as long as their surroundings allow them. You may be thinking this is a very romantic gesture on the part of these gorgeous couples. Sorry to burst your bubble, but this behavior might just be a good way to increase their chances for the female’s eggs to get fertilized...

        Harlequin shrimp have very unique dinning habits that could easily be inspiring for the plot of a horror movie. Although they are very small, they survive on a diet of almost exclusively live starfish much bigger then themselves. With a particular taste for their legs and soft tissues (best eaten with a nice chianti). Most seas tars species are suitable but reportedly Harlequin shrimp cannot eat brittle stars.

      In recent years with the growing aquarium trade, these beauties have also become a major target for people wishing to put them on display in their personal fish tanks. When you search the internet for information on harlequin shrimp, the majority of hits are from sites offering information to aquarium breeders and collectors, which is heartbreaking. The appeal is understandable from an aesthetic standpoint, but we would much prefer to observe them happy and free in their natural habitat. We often get the opportunity to spot them tucked away in the reefs while diving Myanmar.

        Although harlequin shrimp may have questionable dietary practices, we still find them to be magnificent little critters and look forward to every chance to meet them under the seas.