Despite being only small reefs,

they nourish a large number of ocean life.

Despite being only seagrasses,

they are nurseries for sea life, big and small.

Despite being
only coastal trees,

they help keep humidity in sandy soil and block storm wind.

Which island is in the Andaman Sea?

• AKo Man Nai
• BKo Yo
• CKo Libong
• DKo Kradat

Seagrass Ecosystems

Seagrasses are a group of flowering plants that adapts to grow in the sea.
They grow well in shallow water exposed to sunlight.
They are the only group of flowering plants that evolve to return to the sea.
Seagrasses reproduce widely around the shallow water
area of the tropical coasts.

In Thai waters, 13 kinds of seagrasses are found.

They can be divided into 2 types based on a leaf shape:
Linear or oblong leaf shape, for example, enhalus acorides,
syringodium isoetifolium, ruppia maritima (only found in the Gulf of Thailand).
Elliptic leaf shape, for example, halophila ovalis, halophila decipiens,
halophila major (only found in the Andaman Sea).

Seagrass ecosystems

are very important to the coasts because they are areas suitable for living and feeding of large marine life including economic aquatic animals, such as shrimps, shellfish, and crabs.

They are nurseries for developing marine life and a shelter for various kinds of small sea animals, such as fish, shrimps, and crabs.

Moreover, they not only help weaken the strength of water currents flowing toward the shore, and help decrease the pace of coastal erosion, but also help organic matters to sediment and filter filths creating biogeochemical and nutrient cycles in the ecosystems.

Auatic animals found in the seagrass ecosystems

polychaetes, shellfish, shrimps, mantis shrimps, crabs, sea cucumbers, starfish, and varied kinds of fish, such as, Emperor fish, Double-spotted queenfish, Sand whiting, and Anchovy. Moreover, we can find a large animal, such as dugongs and sea turtles which live and feed around this area.

Seagrasses help filter and
improve water quality.

Because their roots hold together the soil, they help decrease soil erosion
and serve as a link between mangrove forests and coral reefs.

Seagrasses in the coasts of Thai waters are still 80% abundant
There are many important seagrass areas in the Gulf of Thailand and the Andaman Sea,
for example, the Tungcar-Savee gulf in Chumphon Province, Ko Talibong in Trang Province,
and Ko Sriboya-Pu, in Krabi Province.

Although the majority of seagrasses in Thai waters is still abundant, some are deteriorated due to many factors:

• The development in the shore area including the construction of bridges, hotels, and piers, including waste water released from communities and tourist attractions
• Global Warming leading to the increase in sea temperature which affects the growth of seagrasses
• Sea navigation cutting leaves of seagrasses and plunging the soil
• Some types of fisheries, such as, shellfish rakes and small trawlers
• Coastal waste water from mining, piers, jetties, and industrial factory

We can easily conserve
seagrass ecosystems

by keeping water sources clean, by treating waste water from households and industrial factories,

by drawing a limit to the use of seagrass areas,

by learning how to rightly benefit from seagrass sources without doing harm.

Beach Forest Ecosystems

We can find beach forests or the flora of beach forests on the coasts that
are a beach with sandy soil areas untouched by sea water. Growing near the shore,
the beach forest plants have arched trunks due to the wind, and are salt-tolerant
(halophytes). The soil around here is salty because it receives salt spray from the sea.

Beach forest plants have a root system that can grow
on the joints and regrow. When their roots grow and
are piled up with sandy soil, they will develop into
a trunk that holds together the sand.

Grasses are a pioneer
species of beach forests,

for example, ravan’s moustache and bayhops. These plants
have a fibrous root system that holds together the sand
like a net. The bayhops’ vines are rooting places for
grass seeds and some types of big trees, such as she-oaks,
screw pines, etc.

Beach plants

such as, crinum lily, beach cabbage, and coast cotton trees
usually grow in groups. Therefore, they serve as a wall blocking
wind and waves for other beach plants that are less
salt-and-wind tolerant.

Because a beach forest does not have a large area,

animals dwelling here
always move around.

Sometimes we might find animals from an evergreen forest come
to feed in a beach forest. We can find mammals, such as, stags,
weasels, fishing cats, leopard cats, boars, macaques, pig-tailed
macaques, pangolins, and wild rabbits. We might find animals from
the group of rodents, squirrels, or bats.

In addition, we also find birds, such as,
barred buttonquails, wild fowls,white-breasted
waterhen, watercocks and various other
kinds of wetland birds.

The beach forest areas in the Southern
region account for only 4,084,592 sq.m.

consisting of the total areas from 6 Provinces including,
Surat Thani, Ranong, Phangnga, Krabi, Trang, and Pattani
(information from the 2009 Mangrove Forest’s Land
Use Classification Project)

Because beach forests are next to the sea, they are often
destroyed and changed into tourist attractions, residences,
and communities. As a result, what is left are mostly small
and deteriorated patches of beach forests.

The exploited and neglected beach forests,
since there are no important economic plants,
however, are very important

because

they not only hold together sandy soil,
but also serve as a barrier to storm
wind and waves from the sea.

They are similar to a balance keeper of the
junction between the sea and the land forests.
They also help keep water and humidity in sandy soil
which is vital for living beings around this area.

Coral Reef Ecosystems

Coral reef ecosystems are ecosystems in tropical
seas and homes to several kinds of animals.
Among them, the most important are “reefs”
Coral reefs in Thailand often grow on the coasts and the
island shores both in the Gulf of Thailand and the Andaman Sea.
The coral reefs grow into its structure by the accumulation of
animals in the hard coral group.

The coral reefs found in Thailand are fringing reefs
growing on the island shores. On the mainland shores
there are not many coral reefs and usually are shallow
water coral reefs. The survey finds that, in Thailand,
there are around 300 kinds of hard corals.

Coral reefs are unique ecosystems that are abundant
because there are many organisms living in them.

As corals consist of limestones in different shapes
and structures, they are porous and suitable for living,
sheltering, feeding, spawning, and nursing babies of
various aquatic animals.

From the survey,

there are more than
800 kinds of fishes living
in coral reefs,

making coral reef ecosystems one of the most biologically diverse
places in the sea. Coral reefs in the coastal areas help protect
the coasts from the direct erosion of waves and currents in monsoon
season. Moreover, coral reefs are sources of sand for beaches.
Thanks to the corrosion of limestone structures and the erosion
made by some marine life and waves, coral reef limestones are
powdered into beautiful white grains of sand.

It is estimated that 50% of calcium carbonate heaping under
the ocean is created by coral reefs.

Corals reefs are deteriorated by
several factors. Natural phenomena,
such as coral bleaching,

or human actions, such as coastal development for tourism,
fisheries, littering, and releasing waste water from human
activities, are key factors that bring about the decline
of coral reefs.

Therefore,

people and tourists must
help conserve coral
reefs together

in order to keep the balance in nature by the following means:

In sea navigation near the shore, mooring the ship to a buoy and no anchoring to the coral reefs.

Putting up a sign for coral reefs to prevent ships from coming close.

Prohibiting fisheries by trawls and strong nets in the coastal areas where coral reefs are.

Promoting the importance and the value of coral reefs conservation.

No selling reefs or making reefs into a souvenir. No buying goods made from reefs.

No littering into the sea.

Princess Maha Chakri Sirindhorn
Natural History Museum

also presents a natural and cultural trail at Ko Bulon Le,
in Satun Province, where beautiful coral reefs are.

In addition to studying nature,

visitors will be able to experience
the culture of the Urak Lawois,

sea people who live in harmony with nature.

Do you know…?

Three quarters of
the world are water

In water resources, be it canals, rivers, seashores,
or deep seas, there is one kind of organisms that will
affect all lives on earth, were it to disappear.

If you want to know what it is,
try panning around.

That’s right! It is
the plankton!
Most of the plankton is invisible to naked eyes.
Despite being this minuscule,

they have indispensable brilliance to them!

Plankton

The word plankton has a Greek root meaning “Drifting”
or “Wanderer”. Plankton refers to small organisms that
float in water and are carried along with the water current
without being able to swim or move on their own.

Plankton is divided into 2 types
based on how it feeds:

Phytoplankton

It can produce food by itself via photosynthesis,
so it usually scatters around the area exposed to
sunlight and can be found in fresh water, salt water,
and brackish water

Zooplankton

It is a small organism floating in water current
unable to produce food by itself, so it needs to
feed on other organisms, such as, phytoplankton,
small organisms, or other suspensions, such as,
shrimp and crab spawns.

Plankton is a very important
organism to the sea.

Phytoplankton is a primary producer in the food chain

as it is food to zooplankton and various marine life including
large animals like whales. The quantity of phytoplankton determines
the quantity of zooplankton and next consumers in the food chain.

Now you know

why the plankton is

small but superb.

No matter how small or big the organisms are,
they are all important to ecosystems.

Click here to download the information
about “plankton in water sources”

Email *

Download the file

Although plankton is this minuscule,

researchers still regularly
discover new kinds of plankton.

Researchers of Princess Maha Chakri Sirindhorn Natural History Museum
have discovered a new kind of plankton named “wavy-bottom water fleas”

Which of these animals is not considered as plankton?

• AMoina
• BJellyfish
• CBlue-green algae
• DShrimps

If plankton disappears,animals in different
ecosystems as well as humans will be affected.

Similar to everything in nature,
if crabs in mangrove forests or small bats in jungles disappear,
there will be impacts on our lives.

10 distinctive coastal animals

you can see at Princess Maha Chakri Sirindhorn Natural History Museum

Marbled Cone

Family : Conidae
Scientific name : Conus marmoreus
Common name : Cone Shells

Dugongs

Family : Dugongidae
Scientific name : Dugong dugon
Common name : Dugong

Land Crabs

Family : Gecarcinidae
Scientific name : Gecarcoidea humei
Common name : Land crab

Finless porpoise

Family : Phocoenidae
Scientific name : Neophocaena phocaenoides
(Cuvier, 1829)
Common name : Finless porpoise

Pacific swallows

Family : Hirundinidae
Scientific name : Hirundo tahitica
(Gmelin, 1789)
Common name : Pacific swallow

Indo-Pacific horseshoe crabs

Family : Limulidae
Scientific name : Tachypleus gigas
(Müller, 1785)
Common name : Indo-Pacific horseshoe crab

Mangrove horseshoe crabs

Family : Limulidae
Scientific name : Carcinoscorpius rotundicauda
(Latreille, 1802)
Common name : Mangrove horseshoe crab

Blue-ringed octopuses

Family : Octopodidae
Scientific name : Hapalochlaena maculosa
(Hoyle, 1883)
Common name : Blue-ringed octopus

Fluted giant clams

Family : Tridacnidae
Scientific name : Tridacna squamosa
(Lamarck, 1819)
Common name : Fluted giant clam

Blue-spotted mudskippers

Family : Gobiidae
Scientific name : Boleophthalmus boddarti
(Pallas, 1770)
Common name : Blue-spotted mudskipper

5 facts about coastal areas
that you might not know before

Did you know?

Do you know that if coral reefs are damaged and completely destroyed, there will be impacts on every human on earth?

Read more

Although coral reefs amount to less than 1% of the earth surface, all of them are habitats for 25% of sea fishes. These sea fishes are important food sources to at least 500 million humans. If coral reefs are ruined, humans will also lack important food sources.

Did you know?

Do you know that seaweeds are oxygen sources of the planet since the primeval time?

Read more

In fact, 70-80% of oxygen in the world are produced by the photosynthesis of seaweeds. Seaweeds also help absorb carbon dioxide dissolved in water. That seaweeds produce oxygen for the natural world since the primeval time is supported by the discovery of blue-green algae or Cyanobacteria fossils which are at least 3,600 million years old. They are considered one of the earliest organisms on earth.

Did you know?

Do you know that squids are the smartest invertebrates?

Read more

Sea squids belong to a group of mollusks that evolves to be able to swim freely. Squids have such an excellent nervous system and a large brain that they might be called the smartest invertebrates. One example of their smartness is
their ability to change their skin color to camouflage in order to protect themselves from harmful enemies.

Did you know?

Do you know that the Southern coastline stretches over 2,400 kilometers and the two sides are different?

Read more

The Southern region of Thailand is a peninsula or a peninsula that extends into the sea. The total coastline of the Gulf of Thailand and the Andaman coast is over 2,400 kilometers or a similar distance from Hat Yai to the Northernmost border of Myanmar adjacent to China. As a result, we have plentiful ocean natural resources. Moreover, the Gulf of Thailand and the Andaman coast are different in origins. The Gulf of Thailand is formed by the emergence of the land, so the sea is relatively shallow, only 50 meters and consists mostly of sediment. On the other hand, the Andaman coast is formed by the submergence of the land, so the sea is ​​3,000 meters deep, very steep and with narrow plains.

Did you know?

Do you know that the Southern region and the Gulf of Thailand used to be grasslands before?

Read more

During the last ice age hundreds of thousands of years ago, the world’s sea level was 120 meters lower than the current level. The Gulf of Thailand then was a connecting land between the islands known as the Sunda Shelf. Wildlife, especially the big size mammals, could travel down to an area where it is now Borneo, Java and Sumatra. There are also many animals, such as hyenas (which have been extinct from the area) and wild deer that stayed in the savannah not migrating down to the rainforests in the lower Southern region.

Coastal ecosystems are important
home to many organisms

If we love and care for our home,
we should protect the home of other creatures as well.

Nowadays, there are many organizations
that play roles in the conservation of
coastal ecosystems and seas. We can help
conserve the seas in many ways too.

Let’s see how many ways you have helped conserve the shoreline.

I have studied coastal problems.
I have collected litters on the shores or in the seas.
I do not collect shells or capture animals as a souvenir.
I do not support eating endangered and vulnerable marine species.
When diving, I do not destroy reefs or habitats of other creatures.
I do not pick or damage the habitats of animals whether on the shores or in the seas.
I have attended a volunteer camp related to marine environment.
I have warned or recommended others to pay more attention to coastal problems.

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The length of the coastline

On the Gulf of Thailand’s side, it is 2,055.18 kilometers long in total On the Andaman Sea’s side, it is 1,093.14 kilometers long in total

Territory

The Gulf of Thailand is divided into two parts based on its geographical characteristics:

• The Eastern Gulf of Thailand starting at the center point of the estuary between Ta Chin and Chao Phraya river and ending at the border to Cambodia
• The Western Gulf of Thailand starting at the center point of the estuary between Ta Chin and Chao Phraya river and ending at the border to Malaysia

The Andaman Sea The sea is open to the Indian Ocean starting at Kra Buri estuary in Ra Nong Province, toward the Strait of Malacca, and ending at the border to Malaysia in Satun Province.

Coastal Characteristics

The Gulf of Thailand’s coasts are emergent. The crust is uplifted causing the lands which used to be under water to emerge. The shapes of the shoreline are often smooth and not very dented.

The Andaman Sea’s coasts are submergent coastline. This type of shores is caused by a low crustal collapse and is usually steep and very dented with plains hardly found.

The Currents

The Gulf of Thailand: the water current flows along the coast from south to north

The Andaman Sea: the water current flows stronger in the northern-southern line than in the eastern-western line and changes according to the seasonal winds

Water Clarity

The Andaman seawater is clearer than the Gulf of Thailand This is because the Gulf of Thailand receives sediments from several rivers, including Chao Phraya, Tha Chin, Mae Klong, and Ta Pi. Moreover, the sediments on the Gulf of Thailand seafloor consist of sludge mixed with shells in greenish gray, black, and dark brown, sand and mud, whereas the sediments on the Andaman seafloor consist of sand and sand mixed with sludge, making the Andaman seawater clearer.

Salinity

The salinity of seawater depends on many factors, such as temperature, depth, and density of water which differ in different areas of the sea. Even in the same body of water in the Gulf of Thailand there are different factors, as a result, it is difficult to tell which sea is saltier.

Seagrass structure

Seagrasses consist of 3 parts:

• Roots: absorb nutrients and minerals from the soil and helps hold the land firmly
• Rhizomes: parts of the stems that creep under the soil.
• A Leaf (Leaf blade): used in photosynthesis. It is important for seagrass classification.

Seagrass reproduction

Seagrasses reproduce in the shallow waters of the tropical coast. Seagrasses can reproduce in two ways:

• Asexual reproduction by branching out new branches or shoots from rhizomes.
• Sexual reproduction by producing flowers and transferring out the pollen via water and waves. When fertilization occurs, female flowers will develop into a fruit whose seeds are for further reproduction.

Dugongs

Dugongs are the only mammal that lives in the seagrass ecosystem. They come to feed on seagrasses that grow about 1 kilometer from the coast, during the high tide both day and night. During the low tide, they live in channels about 4–5 kilometers from the coast.

Economic animal

Economic animal refers to animals that have an economically useful quantity and potential and can bring income into the country. Thailand’s economic animals are: Chickens - can be exported to other countries, either processed or frozen. Black tiger prawns - are popular for farming and can be exported in large numbers.

Are corals also animals?

Corals are closely related to the jellyfish, sea anemones, and corallines, but people often mistake them as plants due to their hard limestone exterior structure which they can create by themselves. Corals are able to forage with tentacles that have poisonous needles for trapping small animals. The tentacles come out from the hard body during the night.

Despite foraging small animals, the real vital energy source of corals comes from the photosynthesis of tiny single-celled algae called Zooxanthellae, which live in coral tissues. The algae generate enough food for the needs of the corals and themselves in an interdependent relationship. Corals reproduce during the full moon by releasing germ cells to the water currents. When fertilized, the eggs hatch into larvae that look like flat worms, which will float to the empty hard surface to develop into corals.

Types of corals found in Thailand

• Hump Corals They look like a wide base stone. They are mostly brown or gray. They are the most common and most numerous kinds. Because they can endure natural disasters and monsoons or even the phenomenon of coral bleaching, they can live for hundreds of years.
• Cauliflower Corals They have a limestone structure in bushes. They are a habitat for crabs, goby, and some types of sea worms. These animals use cauliflower corals as a habitat, food and a shelter from their enemies. In one heap of cauliflower coral, more than a hundred of these animals can be found.
• Staghorn Corals They have a hedged structure or may have a base underneath for the branches to grow. Each hole looks like beautifully arranged flower petals.
• Knobbed Hump Corals They are lumpy and come in a variety of colors, such as red, green and gray. They are sharper than other corals, so they may cut easily when touched.
• Mushroom Corals They look like a mushroom upside down. Unlike other corals, each mushroom coral has one sex. The female produces eggs and the male produces sperms to fertilize in the water.
• Orange Tube Corals They have a beautiful color with an orange extension tube and a yellow mustache. They don’t need to be exposed to sunlight, because they do not have any single cell algae living in their tissues like most corals.

A Coral Bleaching Phenomenon

Coral Bleaching is a condition in which corals expel algae from tissues, as the stressful condition make living together produce a negative effect. This stressful condition can be abnormality of the temperature, the salinity of sea water, the amount of light intensity, etc.

The coral bleaching phenomenon causes the corals to lose the single-celled algae that are an important energy source so they are weakened. If they cannot tolerate this condition, they will eventually die.

If the bleaching begins, it will affect the corals in the same area to gradually die. When the reefs degrade, the reef ecosystems will be affected, in particular, fish society and other organisms that live in coral reefs.

Illegal fishing tools

Excessive fishery that exceeds the nature’s capacity to renew lead to the continuous decline in aquatic animal resources in Thai waters, which may affect the economic security of the country. So, some fishing tools are prohibited to use or own by laws in order to reduce the destruction of aquatic species as following:

• Thrust nets used in motorboats with an exception of the types that are allowed according to the rules set by the Command Center for Combating Illegal Fishing.
• Fish traps and fences or other tools with similar characteristics and methods
• Surrounding nets smaller than 2.5 centimeters in diameter, which are prohibited for night fishing.
• Folding tools with a left and right inlet on the side for trapping fish
• Trawling tools with nets smaller than 5 centimeters
• Other fishing equipment according to the fishing methods, the fishing areas, the sizes of the boats, and other rules set by the Command Center for Combating Illegal Fishing.

Who are the Urak Lawoi people and where are they from?

The Urak Lawoi people, often referred to as "Chao Lay," are ethnic people who inhabit the Andaman coast of Thailand. They usually live on the islands from the Malacca Strait up to the Adang Islands, Koh Lipe, Koh Bulon, Koh Phi Phi, Koh Jum and Koh Lanta. The Urak Lawoi people were originally a large tribe in Malaysia. When the religious conflicts arose, they had to relocate to the islands in the Andaman Sea of ​​Thailand. The Urak Lawois earn their living by fishing, diving and hunting for shellfish, and hunting sea animals for food. They live together as a single family. They use a boat as a vehicle, a tool to make a living and as a house. The men dress in loincloth or topless pants, while women are often dressed in batik cloth with breast covers.

Today the Urak Lawoi people are adapting to changing social conditions. They have changed from the traditional ways of fishing to leasing nets and longtail boats with a motor from the capitalists to find fish. They are now dressed in fashionable clothes and lived in a brick house with galvanized roofs.

Food chain

The food chain is the relationship of living organisms in an ecosystem that are consumed in an order to maintain constant transmission of energy. It consists of producers, consumers, and decomposers. Living things can eat many kinds of food, so in one ecosystem there can be multiple food chains, which may be linked, known as the food web. For ecological balance, what should be there the most are producers. However, there should not be too many organisms of any kind, because it will cause the food chain to lose balance and affect other living things.

Wrong!

Ko Man Nai is an island in the Gulf of Thailand, Rayong Province. The Sea Turtle Sanctuary and the Reef Restoration center are located here.

Wrong!

Ko Yo is an islet in the lower Songkhla Lake, part of Songkhla Province. It is in the wetland area not the coast.

Right!

Ko Libong is an island in Trang Province. It is not only a convening place for protected aquatic species such as dugongs, but also a resting point for a large number of migrating seabirds.

Wrong!

Ko Kradat is an island in the Gulf of Thailand, Trat Province. This island’s geography is different from other typical islands because it is a flat land in the middle of the sea with savanna plants. This place is a habitat for a thousand of deer.

Moina is a kind of plankton.

It is zooplankton in a genus of crustaceans living in fresh water. It is an important food source to fresh and salt water fish. People like to feed it to aquarium fish. Moreover, it can help treat waste water and serve as an indicator of water quality.

Jellyfish are a kind of plankton.

They are classified as zooplankton because they are invertebrates that float along with water currents. Although they live simply by floating in water, the jellyfish are a primitive species that has survived for 600 million years.

Blue-green algae is a kind of phytoplankton.

It can create water bloom, a phenomenon in which there is too much nutrients in the water sources leading algae or plankton to grow rapidly. These nutrients come from chemicals used in agriculture. The water bloom is harmful to animals and humans that consume or touch the water affected by this kind of plankton.

Correct! Shrimps are invertebrates but not plankton.

However, small shrimp spawns can be counted as plankton because they cannot move on their own and need water currents to carry them.

General characteristics:

Cone shells are univalve shells living in the sea. The special things about this type of shell is not only its beauty but also its vicious venom. They stings their preys to paralyze or kill before devouring them. “Cone shells” have such a strong venom that can kill humans in just 15 minutes.

General characteristics:

Dugongs are mammals that evolve from terrestrial animals to live in the sea. Their bodies are like whales and dolphins, which are similar to fish. Their front legs change to paddle-shaped fins, while their hindlegs disappear with only a flat and wide tail remain without hind fins. The females have breasts on the base of their fins. Dugongs are herbivores sharing ancestors with elephants. They feed on seagrasses. They are peaceful and tamed. They are the symbol animal of Trang Province. They are conserved by the partnership between the government and the people. As of now, dugongs are listed as a vulnerable to extinction species by the IUCN.

General characteristics:

Land crabs are large and have a curved slippery smooth carapace in a horizontal egg shape. Their eye sockets are tiny. The edges of their carapace are smooth and without spines. When their mouth closed, there is a kite-shaped gap in the middle. The sides of their mouth are hairless. They have big claws. Their whole body is brown.

Land crabs are in the class of terrestrial crabs which can remain on land for a long period of time. They only need to go into water briefly to change the water in their gills at the bottom of the crab holes that they dig. As a result, there must be underground water underneath the crab holes. In the early stage of life, land crabs must float like plankton in the sea because their mothers spawn them in the water near the shore. Land crab spawns have to feed and molt several times until they look like a mini version of their parents before they enter coastal forests and grow into a new generation of crab parents.

General characteristics:

Adults can reach 2.27 meters long but they are typically less than 2 meters long and around 70-100 kilograms in weight. They have no beak. Their dorsal is smooth without dorsal fin. Their lateral fins are quite large with a pointed tip. Their teeth are not sharp.

They can be found in all provinces adjacent to the sea. They are most commonly found in the Gulf of Thailand. They are usually alone or in two or may stay in a flock of 10-20 in an area with rich food sources. They eat small fish from the surface of the water to the bottom of the water and shrimps and squids.

General characteristics:

They are a very small bird similar to a home swallow but the forehead is more reddish-brown and there are no stripes on the chest. Their neck and chest are yellowish brown. Their tail is short but the outer double tail feathers are slightly longer.

Living along the coast, they hover and feed on insects in the air, especially the flies.

General characteristics:

The carapace is flatter and wider than that of mangrove horseshoe crabs. The tail is raised in a triangular shape. They have ridges with small spines on top of the tail. The carapace is not more than 25 centimeters wide and 35–40 centimeter long. The carapace’s color is lighter than that of mangrove horseshoe crabs.

The size of the Indo-Pacific horseshoe crabs is as large as a rice plate, which is the origin of the name. The Indo-Pacific horseshoe crabs spread throughout the coasts of the Pacific Ocean and the Indian Ocean. They are classified as edible.

General characteristics:

The carapace is round and convex, like an inverted cup. The head is curved and the tail is slender and spherical. The carapace is dull yellowish-green. The total length of the tail is about 40 centimeters.

They are found along the coasts of the Indian Ocean, Southeast Asia and East Asia. In Thailand, they can be found in every province adjacent to the sea. Both meat and eggs are poisonous in every season and should not be consumed. The poison comes from poisonous planktons they consume. And mangrove horseshoe crabs produce their own venom by the toxins from the bacteria in the intestines.

General characteristics:

They are a small cephalopod with blue fluorescent ring on their body and antennae. The body length is around 40 mm. The length of the tentacles is 1.5-2.5 times greater than the body length. The body shape is a round bag with a sharp end. The body is brown with a blue dot ring.

They are classified as an important predator because of their deadly poison. They control the population of marine life. They are a rare near-endangered species of octopuses.

General characteristics:

They are similar to other kinds of giant clams. There is a protruding tissue outside the shell or mantle. The width of the shell is about 40 centimeters.

They use zooxanthellae in photosynthesis and absorbs various substances including wastes, excretes from other animals in the ecosystem, and sediments in the water to synthesize their food. This makes the fluted giant clams both produce food and dispose of wastes in the water at the same time making the water clearer and cleaner. They are now classified as an endangered species.

General characteristics:

They are around 6-8 centimeters in length with the largest at 22 centimeters. The body color is dark and almost black. There are blue dots scattered all over the body which can indicate their mood.

They are found in mangrove forests. They use their strong pectoral to slide, walk and jump. They can stay on land for a long time. In some areas, they are caught for food and kept as pets.