Amazing Cephalopods
large octopus on reef with blue water

These weird and wonderful creatures are always a  treat and cool to see. Real crowd pleasers. Probably the closest thing we have to aliens on earth. With the ability to change colours, Shape, and texture makes them fascinating to watch.  Living predominantly on the reefs,  we are lucky to find them on most of our tours. The most common species we see are the Octopus, Cuttlefish, and squids.

Cephalopods can be characterised by their arms and tentacles, incredible camouflage  and impressive level of  intelligence. Octopuses or octopi, squid and cuttlefish are the most well-known members of the Cephalopoda class of animals. They have all evolved from a common, hard-shelled ancestor (more similar to a nautilus). The word “cephalopod” comes from Greeks and means “head foot,” which perfectly describes animals that have eyes just above their many limbs. 


There are around 300 species of octopus and they are found to be in every ocean. known for their high intelligence and their amazing ability to blend into their surroundings. They are some of the most fascinating creatures to observe. The octopus is equipped with three hearts: one that pumps blood through the body (including the 8 arms), and two that pump blood through the gills. It is an interesting fact to know that the octopus does not have tentacles. They are in fact arms. Octopus are the only marine animals, apart from the Cetacean family (Whales & Dolphins), that demonstrate primitive problem-solving and pattern recognition skills. But whatever kind of intelligence they possess, it’s different from the human brain, probably closer to a cat. The skin is covered by three types of specialised skin cells, these can quickly change their colour,  allowing them to easily blend in with its surroundings. While it is very intelligent they can also be very inquisitive. Which is great for us to watch them, or photograph. We can get some great interactions if we are lucky. Octopuses are great predators. Octopuses are carnivores, and  feed on small fishes, crabs, clams, snails, and even other octopuses. They typically hunt alone, ambushing  their prey and wrapping it in the webbing between their arms. Just recently we had a Wunderpus while snorkelling in Alor. This is a very rare octopus and such a surprise. We found it while doing a muck snorkel in only 1.5 metres of water. But seemed more interested in us than wanting to hide away. Giving our group a great opportunity to watch it. 


There are over 100 species of cuttlefish. Cuttlefish also have the ability to change their colour to blend in with their surroundings, just like the octopus. This happens due to  millions of pigment cells, called chromatophores, that attach to the muscles in their skin. When these muscles tense, the pigment is released into the cuttlefish’s outer skin layer and can control the cuttlefish’s colour and even the pattern and texture.. The cuttlefish has two long tentacles that are used to quickly grasp its prey, which it then manipulates using its 8 arms. Cuttlefish are also great predators who feed on other mollusks, fish, and crabs. They may also be cannibalistic. They have a beak in the middle of their arms that they can use to break the shells of crabs. Cuttlefish have a small fin that goes around their midsection, which looks like a see through  skirt. They use this fin for small movements . When a quick movement is needed, they can blast water from a jet-propulsion tube in their mantle. Cuttlefish have a oval bone called a cuttlebone. This bone is used to regulate buoyancy using compartments that can be filled with gas and/or water. Because they are so well camouflaged they can be tricky to spot. Fortunately with guides with eagle eyes we spot them on most snorkelling trips around Indonesia. One of my favourite spots to see them is in Komodo – Indonesia. At the Komodo Resort house reef we have often found them there. They come into the shallow reef to mate and lay their eggs. Which is ideal for us to watch and observe this behaviour.


 Over 200 species of squid can be found in every ocean. They can nomally be found in schools, but also can be solitary. While some squid live in shallow waters, the deepest recording of a bigfin squid was a staggering three miles below the surface. They come in all sizes: from the pygmy squid that is the size of a pinky fingernail to giant squid which may reach up to 18 metres long.  Unlike the octopus, which has no skeleton, squid have an internal shell called a gladius, or pen. This stiff backbone-like structure supports the mantle and gives tissue and muscles something to attach to so the squid can keep its shape. The  squid’s mouth can be found at the base of the mantle. The beak is used  for killing and eating prey, which include fish, crustaceans, and other squid. Surrounding the mouth are 2 long tentacles with suction rings at the tips that the squid uses to grab prey and 8 arms that it uses to hold its meal while it eats. Squid  also have large brains making them highly intelligent. They can rapidly change skin colour using special pigment filled cells called chromatophores. They can use this to hide from danger and warn off potential attackers, or even use the patterns on the skin that allows them to communicate with other squid while remaining camouflaged to potentiol predators. And that’s not all. Squid can also make themselves transparent. We are really fortunate to see them often on our snorkel trips. They really love to hang mid water above the reefs. Our trips in Belize have been very fruitful for these beautiful animals. 

In conclusion any of our trips whether it be snorkelling in Indonesia or our Carribean trips to Belize and Cuba. This gives you a great opportunity to watch these amazing creatures. As a guide I am always so happy when we find one of them. Could spend hours just watching them move across the reef. Night snorkelling is always a great way to increase the chances of seeing the octopus hunting. 

About Author

Marcus Blake
Marcus joined the Snorkel Venture team in 2021. Prior to that for five years was managing dive and snorkel operations at Komodo Resort in Indonesia. He has been fortunate enough to have worked and travelled to some of the best snorkel locations in the world. Giving him a wealth of experience and knowledge of the oceans.