Weird creature of the month – October

Dugong is a large marine mammal, together with manatees, they belong to order of Sirenia, which  today has only four living species.

Dugongs can weigh as much as 380 kg and reach up to 3 m in length. They can live long, oldest recorded specimen reached age of 73. They have several nick names like Sea Cow, Sea Pig, Lady of the Sea, the last one comes from the Malay word duyung. Dugongs have been on the hunters list for thousands of years due their meat and oil. Closest relative to dugong, the Steller’s sea cow was hunted down in the 18^th century. Today authorities are trying to save dugongs with different conservation and protection projects.

In some cultures they are legendary for their medicinal purposes. In Southern China catching dugong was thought to bring bad luck.

Did you know that actually dugongs are considered to be the inspiration for Mermaids?

Dugong populates more than 37 countries throughout Indo-Pacific. Biggest population you can find is from coast of Northern Australia. The sea of Trang province in the Andaman Sea is home to dugong as the area is rich with sea grass.

Dugongs have few natural predators, although animals such as crocodiles, orcas, and sharks pose a threat to the young.

Dugongs are called as “sea cows” because their diet consists mainly of sea-grass. Occasionally they eat jellyfish, sea squirts, and shellfish. Dugong can spend all their life in sea water, without having need for fresh water.

Due to their poor eyesight, dugongs often use smell to locate edible plants. They dig up an entire plant and then shake it to remove the sand before eating it. Sometimes they collect first a pile of plants before eating it. The muscular upper lip is used to dig the plants out, witch leaves furrows in the sand in their path. They may travel long distances to find food. As they need a lot of sea grass then usually we can’t find many dugongs in the same area. They spend most of their lives solitary or in pairs.

Dugongs may stay under water up to six minutes, dive down to 39 meters, but most probably you can meet dugong at depth of around 10 meters. Most of the dugongs in Thailand we can find in Trang province (2013 about 110-125 individuals), where a much smaller population lives in Gulf of Thailand.

Weird creature of the month – August

Gobies is by far the largest family of fish with approximately 1,500 known species over the whole world. Just like its near relative the blenny, the goby usually lives in burrows and holes and are territorial, were most species are around 10cm in size.

The goby is a relatively social animal that lives with its partner for a longer period. The male goby attracts the female by making noises, and it is proven that these sounds are crucial for the choice of partner. The sound is made by the male gathering an amount of water in the mouth and quickly spurting it out with a massive force.

Another very interesting feature many of the gobies have around our dive sites is their partnership with shrimps. They live in a symbiotic relationship and depend on each other for survival. The shrimp is very skilful in digging, finding food and making a burrow. However, since it is blind, it makes the shrimp a very easy snack for predators.

The goby on the other hand, has very good eyesight but lacks the skill of digging, hence also making it an easy target. To survive they work together with the shrimp where the fish sit outside the excavation site as a lookout.

If you look carefully at the shrimp you can see the tentacles in close contact with the goby. If a predator would close in the shrimp can wiggle the tail, alarming the shrimp. The shrimp will then move to the side so the fish can swim in and hide.

If you avoid exaggerated movement and breathe carefully, you can see the shrimp and the goby on the sea floor all over Phi Phi Islands and Koh Haa.

Weird creature of the month – July

While scuba diving sandy sea beds you may come across what initially appears to be a colony of sea grass sprouting from the sea bottom, but as you get closer the grass begins to shrink and eventually disappear like it was never there to begin with. What you just witnessed was not a mirage, the effects of narcosis or your mind playing tricks on you, but simply one of the most interesting varieties of conger eels known as the Garden Eel.

Garden eels live in large groups in underwater sandbanks. Each eel has to make its own burrow that goes straight down into the sand. They dig these burrows with their tails using a gland in their tail which secretes a slime that makes the sand stick together. This technique ensures that the eels burrow does not collapse. The garden eel eats without leaving its burrow keeps its tail inside and sticks the rest of its body out. With its head exposed garden eels spend most of the day attempting to capture zooplankton that the current delivers them. When it gets scared, it takes its whole body into the burrow closing the burrow with a mucus plug to protect itself. This is the secret to the Garden Eels vanishing act, leaving no trace of the burrow as it retreats.

Did you know? The Garden Eel get its name from their practice of poking their heads from their burrows looking like they are growing as plants in a garden.

you can easily find garden eels at the Similan Islands

Weird creature of the month – June

Sea Angel (gymnosomata)

Light reflects through tiny creatures fluttering their translucent wings. They seem to be flying, even thou they are in the blues of our seas. These beautiful organisms are the proof of the existence of angels, angels with horns. The angel-like appearance resembles that of their huge importance in ecosystem. They are a parts of the food chain serving as the food to fishes as well as whales. Their horns may symbolically remind of the “devilish” side of these angels as predators.

Sea angels are very small swimming sea slugs found around the world in arctic and tropic seas usually in the upper 0-20m of water. They belong to marine mollusks and are divided into six subgroups, with differences mostly due to a different geographical habitat. Sea angels lack the mollusks shell, which explains their scientific name: Gymnosomata (Greek: naked body).

Their body is gelatinous, like that of a jellyfish, and because of its shape, has been referred to being perfectly streamlined for swimming. Their gastropod has developed into a wing-or fin- like extensions, which allows them to perform a rowing or “flying” motion. Evolutionary adaptation on losing the shell and developing fins, unlike on other sea slugs, has given the sea angels the liberty of swimming freely in the oceans. Because of their unique swimming style and highly developed muscles and body shape, sea angels have been the subject to a wide variety of researches in the neurobiology of swimming.

Sea angels are carnivores and adapted in size and behavior to their main prey, sea butterflies or so called sea devils. They catch the butterflies with tentacles located in their mouth. Thus even the largest of sea angels grows only up to 5cm in size. They don’t have eyes, but instead use chemical detectors to find their prey. The chemical detectors are located in the head, looking like horns.

The Antarctic sea angel synthesizes a deterrent, which keeps the predators from eating them. Some other small sea animals use this unique benefit by carrying a sea angel around in order to protect themselves as well. The arctic sea angels have been reported to be found even in densities of 300 to a cubic meter, whereas southern areas densities don’t reach even close. Sea angels have both male and female reproductive organs. They fertilize internally and then release a mass of eggs to float freely until the eggs hatch.

Sea angels have been widely used as visual models in movies and cartoon characters because of their extraordinary looks. In Japan they even sell scientifically designed aquariums for those keeping the delicate arctic sea angels (Clionidae) as pets.

Weird creature of the month – April

Flatworms, also called “planarians,” are found just about everywhere there is water. There are many different species of flatworms, some live here, in the Andaman Sea off the coast of Thailand.

Some flatworms can be more than 10 m long, the longest one have been 30 m. They have no body cavity and no circulatory and respiratory organs. With no restriction in shape means the worms can grow flat which gives them their name.

This flattened shape allows oxygen and nutrients to pass through by diffusion. The digestive cavity has only one opening for both the intake of nutrients and removal of undigested wastes, which means that the food cannot be processed continuously.

Flatworms are one of the simplest animal groups with a basic central nervous system and eyes that can only see the difference between light and dark. Some worms lack eyes as they are completely parasitic living in or on another animal.

They are hermaphrodite which means they “choose” their gender during mating. This procedure is quite particular as flatworms use their “penis” to fight each other. The first one to penetrate the other will inject sperm and become male. For the flatworms, this contest is serious business. Mating is a fight because the worm that assumes the female role then must expend considerable energy caring for the developing eggs.