The dugong is a marine mammal which they share the same ancestors to elephants. 55 million years ago, the evolution of dugong start from living on land then, move to the water. Since then, they had never returned to the land, like dolphins and whales
General appearance of dugong
Ears : The dugong have small ears but do not have a pinna. There are small openings on both sides of the head, behind the eye. The ear of dugong can be absorbed the sound well in the water which makes the dugongs a one of marines that can communicates underwater.
Eyes : There are 2 small eyes on both sides of the head with a thin eyelid that can be functioned which help to see well both underwater and above the water including the dim place. Once the dugongs swim above the water for a long time, their body will excrete the excess minerals to maintain the body’s balance of the minerals. Those excess minerals will be excreted as mucus from eyes which look like dugongs are crying when they were caught.
Nose : The nose of dugong locate at the end of the top of the head. There are 2 nostril, which have thick pads that can be functioned. The thick pads are closed when diving and breathing above the water which only the top of the head part can be seen above the water. They are breathing by blow out the used air and inhale the new air in. This will take just only 3 seconds so that they can dive under the sea about 6 minutes long.
Mouth : The mouth locate at the dorsoventral (lower) part of head. The upper lip is a large and thick which looks like a pig’s nose. These nose muscles can be well controlled so that can help to grasp the seagrass into the mouth that is suitable for eating. The lower lip is a cartilage bar covered with soft tissue that is used for digging sand.
Teeth : The dugong has 6 pairs of molars that they are gradually growing and getting eroded as the time goes by. So, the old dugongs will have only 2-3 pairs of teeth left. The function of dugongs’ teeth are for cutting down the seagrass. The juvenile(young) dugong had 2 pairs of incisor teeth at the front of the upper jaw which are called fangs or tusks. The front pair of incisor teeth are smaller and will be eroded gradually and gone at the age of 12-15, while the back pair of small incisor teeth will be existed throughout the dugong’s life. Therefore, the dugong’s teeth are very important in the age determination. Because only the teeth that are exists throughout their life.
Skin and skin color : The skin layer of the dugong is very thick with rough and short hairs all over the body like elephant skin. There are lots of hair around the lower part of the lip which is used to feel or find their food. Dugong has a grayish brown skin. The upper part of the body, such as the head, neck, the upper part of the front legs and the tail are darker than the lower part of the body.
Body shape : Dugong bodies are chubby but, front and back part are leaner than the center part of the body. This helps dugong to move in the water easily. The dugongs do not have a dorsal(back) fin, their tails are divided into 2 part parallel to the ground, waving up and down to swim in order to move forward. The maximun body length is approximately 3 meters, their weight are about 400 kilograms.
Gender appearance : We can determine from the distance between the anal and the genital opening. The distance between the anal and the genital opening of male dugong is longer than female and the position of the anal and genital opening of female are very close.
Breast : The breast and nipples of the dugong are located on both thigh of their legs, which can be found in both male and female. The nipples of young female dugongs are like small lump then expand when they are pregnant.
General biology of dugong
Size and weight: The maximum length is 3.3 meters(in Thailand, 2.87 meters) and the maximun weight is around 400 kilograms(in Thailand, 358 kilograms). There is not much differences between males and females. The newborn size is 1-1.5 meters and about 20 kilograms according to the report(in Thailand, 0.97 meters and 14 kilograms).
Food and habitat: Dugongs eat various type of seagrass and sometimes seaweed. The wild dugongs eat about 3-5% of body weight per day whereas the captive dugongs can eat up to 10% of body weight per day. The dugong usually live near the shore where there are lots of seagrass.
Biology and Behavior: The mature age of Dugongs is 9-10 years olds. The gestation period is around 13-14 months with only one offering per gestation. The newborn dugongs will learn how to eat seagrass the same time they start drinking breast milk. The dugong mothers will take care of their baby around 2 years. Their life span is about 70 years old. The dugong usually live in a small groups of 5-6 and they can live together in the large group of more than 100 but, the living alone dugong can be found sometimes. The average swim speed is 10 kilometers per hours, dugong usually prefer to swim with short distance
The Surgeonfish outstanding characteristic is the lance like spines or keeled bony plates, one or more on either side of the tail which are dangerously sharp difference upon family. Some of them be able to spread and fold like pocket knife. The thorn tails has venom similar to Lion fish and Estuarine stonefish but Surgeonfish’ toxicity with a smaller resultant value indicating a higher level of toxicity from Lion fish and Estuarine stonefish. There are have incisiform teeth in single row both of upper and lower teeth used for grazing on food. Surgeonfish is diurnal animal, they are grazing algae coating on coral. The Surgeonfish’s grazing algae coating on coral makes the coral photosynthesis and healthy. Thus, Surgeonfish has more importance for the ecology.
Scrawled Filefish or Scribbled leatherjacket filefish
Scrawled Filefish is the bony fish, the Scrawled filefishcan be observed in lagoons, coral and rocky reefs, seaweed fields, and wrecks, depth 3 – 20 m.
The outstanding characteristic body irregular blue lines and spots are distributed on the body mixed with some black spots mainly on the head and long tail like paddle.
Young Scrawled Filefish can be observed in open warm-ocean mature they live close to coastal.
Scrawled Filefish have a large choice for its meals like small crustaceans, algae, gorgonians, sea anemones, tunicates, fire coral, and Hydrozoa.
The mature size fish which can grow up to 110 cm (3.6 ft) in length.
Scrawled Filefish, found in the Atlantic Ocean, the Indian Ocean, and the Pacific Ocean.
Eagle ray has many different common names, including white-spotted eagle ray, bonnet skate, bonnet ray, duckbill ray and spotted duck-billed ray.
Eagle ray are a group of cartilaginous fishes in family Myliobatidae. This ray can be identified by its dark dorsal surface covered in white spots or rings. They are live along the open coast in warm waters throughout the world in depths of 1 to 30 m (3 to 98 ft). Their can be found globally in tropical regions from the Indo-Pacific region from the western Pacific Ocean, the Indian Ocean, and the western Atlantic Ocean. Their flat body helps them to swim near the bottom of the ocean looking for preys on bay and sludge area. Eagle ray species usually feed on bivalves, crabs, shrimps, mollusks, whelks and various smaller fishes by specialized chevron-shaped tooth structure helps it to crush. Eagle ray is swim well and can be raises above the water surface in meters. Eagle rays have flat disk-shaped bodies, deep blue or black with white spots on top with a white underbelly. Their tails are longer than those of other rays and may have 2 – 6 venomous spines. This ray species is ovoviviparous, meaning their eggs develop and hatch inside the body of the female rays. A female gives birth to 1 to 6 young Rays per time. Adult Rays of this species can grow up to 16 feet (5 meters) in length including their long tail. Young Spotted Eagle Rays measure between 17 cm and 35 cm in width at the time of birth. Eagle rays, in common with many other rays, often fall victim to sharks such as the tiger shark, the lemon shark, the bull shark, the silver tip shark, and the great hammerhead shark.
Archer fish or Spinnerfish
1. Archer fish be able to shooting with water droplets from their specialized mouths for preying on insects and other small animals.
2. Archer fish can be found in salty waters and mangroves, but can also be found in the open ocean, as well as far in fresh water.
3. The Archer fish will make multiple shots if the first one fails. For example, the experiment by academician tie the victim with sticky glue then let the Archer fish shooting with water droplets to victim but the victim do not drop they are multiple shots. The next day, academician experiment as it was with old victim the Archer fish do not shots. The experimental results is the Archer fish have memorization, they do not repeatedly shooting (learn from experience) until the victim changed.
4. Sizes are fairly small, typically up to about 5–10 cm, but T. chatareus can reach 40 cm.
5. The Archer fish eyes be able to roll while looking for the victim to find the best shooting point.
6. They can shooting to bring down insects and other prey up to 2 m. – 3 m. above the water’s surface.
7. If the victim are short distance be able to jump over to catch, they will immediately catch.
8. Young archerfish start shooting when they are about 2.5 cm.
9. It has also been determined in an experimental context that archerfish were able to benefit from observational learning by watching a performing group member, mature archerfish possibility is improved that at least one shots will hit its target.
Spot coral crab is the sea animal, oval armature, smooth surface, armature edge is cream- brown color, back armature have 11 brown spots , 4 wavy lines between the eyes.
When larvae crabs hatch from the egg and float in the sea called Zoea. They slough off many times around 15-20 day until develop to be small leg celled Megalopa takes 15-20 day but still float like a plankton, after that develop their shape to be parent, and stage of down to the ground called Juvenile, they going to slough off and grow up to be adult.
After female crab slough off they will mate with male crab and male crab release sperm into the female oviduct, female crabs can store the male sperm until her eggs are ready to be released.
Sea urchin and various shellfish by using their claw to crack.
Parrotfish is the bony fish ( Family: Scaridae ), Maximum sizes reaching to 30 – 50 cm. General characteristics similar to Labridae family, their teeth is sharp and hook-shaped similar to parrot mouth the origin of their named. The parrotfish beak can contract and expand, big fish scale, intermittent lateral line. They normally live together when looking for food. The way they swim look elegant like the birds are flying in the air. Parrotfish is colorful, male colorful more than female, female is oval long body. Mostly of their concave caudal fin, the upper and bottom edge caudal fin is sticking out. They mouth similar to parrot mouth for food scrape and also have another set in throat, while they biting will sound. They defecate is sediment that beneficial for coral reef. They can change their sex, diurnal animal, sleep at night, they sleep in the rock nook area and release the mucus to wrap the body for protect themselves from various sea animals such as helminth, parasite
Dawkinsia filamentosa (Blackspot barb, Filamented barb, Mahecola barb)
Dawkinsia filamentosa is a small freshwater fish in Cyprinidae family. There are long flat body, yellow-pink color, dorsal fin pectoral fin and caudal fin is faded red, upper and bottom caudal edge fin is black, the bottom of caudal fin have big black spot. Males Dawkinsia filamentosa are slimmer and aflutter fin than female. Estimated length is 3-5 cm. Behavior is lived together, average age is 4 year. Well known as ornamental fish.
The spawn hatch to be fish around 25 hour upon water temperature, Newborn hatch larval fish eat plankton, their shape look like their parent.
Males Dawkinsia filamentosa are colorful red lips, red fin, and red tail, females Dawkinsia filamentosa are faded color but larger size. The fish size that will be ready for math are approximately 3-5 cm. The Dawkinsia filamentosa is cling type spawn can be lay down the eggs all the year. When the female lay down the eggs around 25 days after that they can breeding again.
Small aquatic animals and insect.
The species is most commonly found in coastal floodplains near the Southwest Indian states of Kerala, Tamil Nadu and Karnataka.