There are 74 species of mangrove trees in Thailand. Mangrove forests provide both food and shelter for many living organisms. The soil in a mangrove forest is similar to that of a tropical rainforest. This is because the nutrients in the soil are very close to the surface. In both rain forests and mangrove forests, the trees have a very shallow root system.
The mud is actually a very important part of the food chain which depends on mangrove later down the line. First of all, the mangrove trees break up waves. Once the waves are not disturbing the water, the fine particles in the water combined with the mangrove tree bark and leaves form sediment. This allows algae to grow in the sediment. This is the start of the food chain. The algae is food for snails. Decomposed leaves are food for crabs and prawn.
The decomposing leaves and bark are eaten by bacteria and fungi. The tide carries the nutrients (food) particles out of the mangrove forest into deeper water (Phang Nga Bay). This becomes food for plankton (which is food for whales), algae, and the mangrove trees too. Mullet (a species of fish very common in Phang Nga Bay) also feed directly on the decomposing leaves. In fact, the amount of protein generated directly from the eating of decomposed mangrove leaves and bark is much higher in mangrove than in any other source in the world!
The tangled roots of mangrove trees provide shelter for small fish from bigger fish. The little fish go into the root system to keep from getting eaten. This allows the little fish to survive to become bigger fish. So, these bigger fish then try to catch other littler fish. The littler fish, of course, then swim into the roots to keep away from the big guys. Mangrove forests are the breeding grounds for a variety of fish species. Many of these fish species are very important to the commericial fishermen. Some are food for bigger fish. Without the mangrove, many of the pelagic fish species would suffer.
Mangrove trees also help filter out sediment from the water. In other words, the clear water in the southern end of Phang Nga Bay is dependent on the mangrove in the northern end of the bay. Sediment prohibits light from penetrating as deep through the water. Coral is adversely affected by sediment in the water. Therefore, if the mangrove in the north is cut down, the coral in the south is in danger of dying.
Birds rely on the mangrove trees both because of the insects and the flowers found on the trees. Spiders live on the trees too. Both terrestrial species (land birds) and sea birds frequent the forests. The most common terrestrial bird species found in southern Thailand feeding on the mudflats and in the shallow water include Pacific Reef Egrets, Chinese Pond Herons, Common Sandpipers (very common in Talin), Little Herons (often seen walking through the mangled roots), White-breasted Waterhens, Common Redshanks (common in Talin), Rufus-necked Stints (common in Krabi river), and a few other less common species. Sitting in the mangrove trees watching for fish or shrimp (prawn) are a variety of kingfishers. The Brown-winged Kingfisher, Black-capped Kingfisher, Common Kingfisher, and the Collared Kingfisher are the most common. Actually, there are at least 204 species of birds that have been recorded in Thailand’s mangrove forests!
Bats can be found hanging out in the caves in mangrove areas. One of the most important species of bats to inhabit (live in) the mangrove forests are the Fruit Bats (commonly called Flying Foxes). Though they can be found in other habitats, the mangrove is one important environment for them. If you like durian, you should like the fruit bat because they pollinate many kinds of durian. In fact, they are the sole pollinators of some species.
Soldier crabs can be seen by the hundreds at low tide. Fiddler crabs and several other species share the mudflats with them. 54 species of crabs have been recorded in the mangrove forests of Thailand. Crab Eating Macaques (monkeys) eat the crabs. So do birds and otters.
All of this eating on the ground is being watched from above by birds such as Brahminy Kites and White-bellied Sea Eagles. They eat other smaller animals in addition to fish.
Mangrove forests are not major breeding grounds for mosquitoes! They require a certain amount of salinity which is usually not found in a mangrove forest anywhere except the intertidal zone. Cutting down mangrove forests to control mosquitoes is rather foolish. The conditions become better suited to mosquito breeding if the trees are cut down because it opens up the intertidal area by allowing more sunlight to get through.
There are many different species of mosquitoes. The larvae (babies) of the differing species require certain levels of salinity, certain types of soil or mud, a certain amount of water movement (tidal movement) and they often need to be in the neighborhood of certain animals (for blood - food). Rubbish is the perfect baby mosquito environment for many species of mosquito. A broken bottle or other type of container can accommodate (shelter) a lot of baby mosquitoes.
Therefore, unfortunately, much of Phang Nga Bay and some of the more popular tourist destinations throughout South East Asia are feeding spot for these pests.
On the other hand, mosquitoes are food for many species of birds such as the Edible-nest Swiftlets and other swifts, Swallows, Martins and Bee-eaters. All of these species of birds are known as aerial insectivores. That means that they eat insects while flying. Mosquitoes are an important food source for them.
There is a fine line between a natural setting and one that humans have impacted. Most of the time when humans interfere with natural balances, it's like working a Rubic's cube... one side looks nice, but...
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