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Villagers' Perceptions of Mangrove Resources

Villagers living in mangrove areas use mangrove trees for their basic subsistence in the form of fuelwood, for construction of houses and fishing gear, and for catching marine animals. All the Had Sai Khao residents and most families in Ko Lao (70-80 per cent) viewed the mangrove forest primarily as the source of forestry and fishery products for daily life. About 20-30 per cent of Ko Lao households expressed no opinion on this topic.

Long-term residents, who had lived in Ko Lao for about 10 years and in Had Sai Khao for almost 20 years, said that more of the forest is being destroyed every year. About 65 per cent of the mangrove villagers in Ko Lao and 80 per cent in Had Sai Khao believed that the main cause of destruction is the cutting of trees by concessionaires, whom the villagers called "the owners of the charcoal kilns."

Residents of both villages believed that the population of marine animals declined after mangrove forests were destroyed. They also said that their daily catch of fish, shrimp, and crabs is less now than 10 or 20 years ago. They believed this resulted from the destruction of the mangrove forest and from the increase in the number of people who had come to live in and use the mangrove area.

TABLE 10. Estimated amount of wood used in the construction of three houses in Ko Lao and Had Sai Khao


Estimated volume (m)

4 x 4m
6 x 5m
8 x 6m
Posts 12 - 18 8 - 10 16 - - 4.1
8 - 12 6 - 8 35 - - 3.2
10 - 16 8 - 10 16 - 3.2 -
8 - 10 6 - 8 18 - 1.1 -
10 - 16 8 - 10 18 3.6 - -
Bracing members 6-8 6-8 10 0.4 - -
Beams 10-16 8 12 - - 1.9
10 - 16 7 10 - 1.4 -
10-16 6 8 1.0 - -
Subflooring 8- 10 8 36 - - 2.7
6-8 7 36 - 1.3 -
6-8 6 36 1.1 - -
Roof frame 6-8 8 30 - - 1.2
6-8 6-8 26 - 1.0 -
4-6 6 20 0.4 - -
Wall frame 4-6 6-8 30 - 0.7 -
4-6 6 24 0.4 - -
Floor 6 - 8 6- 8 90 - - 3.6
4 - 6 6 62 - 1.1 -
4-6 4-5 58 0.8 - -
Platform 6-8 4-6 86 - - 2.6
4 - 6 4 - 6 68 - 1.2 -
4 - 6 4 - 6 60 1.0 - -
Total volume       8.7 11.0 19.3

Ko Lao and Had Sai Khao villagers complained that most of the benefit from the use of mangrove forests goes to the concessionaires. They would like to see the mangrove forest protected mainly for fishery production to assure continuation of their daily subsistence. Mangrove residents, particularly those in Had Sai Khao village, wanted the Royal Forest Department to allow them to cut at least enough mangrove trees for fuel, construction of houses, and fishing equipment.

Villagers believed that the concessionaires, who obtain the greatest benefit from the forest, should take responsibility for protecting the forest from illegal cutting, maintaining the balance of the ecological system and sustaining both forestry and fishery resources. Mangrove villagers would like to take over the responsibility for protection of forests around the villages, if the concessionaires would hire them. They also wanted to work in such activities as planting and logging, in order to earn cash income for their daily subsistence, but the concessionaries have never hired them. Concessionaires usually bring in their own labourers from elsewhere.

Few Ko Lao villagers indicated that they knew about the roles of concessionaires and government foresters in the management and use of mangrove resources. The level of communication between the Ko Lao villagers and the concessionaires is very low. Had Sai Khao villagers have more contact with the concessionaires and government foresters. The village headman or some other villagers used to report to the chief of the Mangrove Management Unit and the research scientists at the Mangrove Research Station or to the concessionaires when they saw people from other villages cutting mangrove trees illegally.

The perceptions of Ko Lao and Had Sai Khao villagers concerning most aspects of the mangrove forests were very similar except for their beliefs about protection of the forest. Most of the people in Had Sai Khao believed in forest spirits. They had built a small house for the mangrove-forest spirit (fig. 13) and made offerings to it. They believed that the spirit was effective in preventing anyone from destroying the forest and had caused the forest near Had Sai Khao to be more fertile than in other parts of this area. No spirit house was seen in Ko Lao.

The Buddhists at Ko Lao village seemed to have more understanding of the ecology of mangrove forests and the processes of mangrove management and utilization than the Muslims. One probable reason is that the Buddhists in general were better educated and also had more opportunity to communicate with people whose work is related to mangrove forests, such as forest officers from the Mangrove Management Unit, concessionaires, and workers at the charcoal kilns. The language barrier was also a problem for some of the Muslim people, but it was not serious because only a few of them (mostly older men) could not speak Thai. In addition, the Muslims usually worked with other Muslims because they wanted to avoid quarrels with Buddhists living in the same village or in other villages. It was learned that they once had a quarrel with Buddhists from other villages about cutting trees and catching marine animals.


Research Orientation

Fishing methods and the species caught were studied at Ko Lao and Had Sai Khao through observation, participation in fishery activities, and interviews. The study was aimed at improving the life of small-scale fisherfolk in these two villages by increasing their daily earnings.

Ko Lao and Had Sai Khao have relatively rich natural resources for fishing and for gathering mangrove forest products. An appreciation of their ethic of selfsufficiency and of the working symbiosis between the people and their environment (where preservation of biological diversity is essential for maintaining options for future generations) was a prerequisite for this investigation. The programme studied the basic needs of the inhabitants of the villages. food, safe water, clothing, shelter, health, and education, consistent with the goals of the Fifth National Socio-economic and Development Plan.

Capture Fishery

The methods used in capture fishery in different maritime provinces vary, but some common fishing methods were used by the villagers of Ko Lao and Had Sai Khao. In determining the efficiency of capture fisheries, one must take into account the kinds of fishing gear and the total catch. Fishing is the main occupation in both Ko Lao and Had Sai Khao. Because Ko Lao households generally used only small to medium-sized fishing boats, their income was generally lower than that of Had Sai Khao households. The people live at the edge of the land, close to the mangrove forest. Because their boats are small, their fishing is confined to the inshore and near-shore zones. June to October is the best period for fishing these two zones, and so income is not spread evenly through the year.

Fishing Gear

Only a few of the types of fishing operations traditionally practiced in Thailand are carried out along the shores of Ko Lao, Had Sai Khao, and adjacent estuaries. The gear varies in structure and size, as described below.

Scissor nets. In Ko Lao mysids and other small crustaceans such as a species of Acetes are caught extensively on the shallow sandy mud flats with brineshrimp scissor nets. The scissor net consists of a finemesh bag net mounted on two long, slender bamboo poles. Wooden shoes are attached to the lower ends of the poles to prevent them from sticking in the mud (see fig. 14). Small scissor nets are operated by hand, but the larger ones are generally operated from motorized boats. The small crustaceans are harvested from the sandy mud at depths of 30 to 120 cm. They seem to be abundant during the rainy season, from May to August. They occasionally disappear when scissor nets of a larger type used to catch fish and penaeid shrimp are employed in the shallow waters, causing high turbidity. The brine-shrimp scissor net is used only by Ko Lao fishers.

Push nets. About 28 per cent of the total shrimp catch (excluding mysids) was taken in push nets, consisting of a bag of fine mesh (approximately 0.8-1.8 cm) mounted on two sturdy bamboo poles about 5 to 8 m long. This gear is operated from a motorized boat of 60 to 220 hp. by two workers. The catch also includes young and juvenile fish, crabs, and molluscs. This type of net is commonly used by the people of Had Sai Khao village.

Barrier nets. Often the mouth of a creek or channel in the mangrove forest is closed with a barrier net, consisting of several nets connected, up to about 100 m in length. The lower side of the net is attached to the mud flat at low tide with small pieces of bamboo. Each end of the net is mounted on a large, strong bamboo pole so that it can be stretched across the waterway. At high tide the fishermen lift the upper side of the net to the surface of the water to trap fish when the tide ebbs. The size of fish caught depends on the size of the mesh, which is about 2.5 to 5 cm. Fish of economically important species from the catch may be kept alive in bamboo cages in order to get a higher price.

Crab net traps. Baited traps are used by the people of both villages to catch mangrove crabs (Scylla serrata). The crabs are caught mainly for household consumption. The simple gear consists of a ring of bamboo about 45 cm in diameter mounted about 30 cm above the lower, pointed end of a thin mangrove pole, with a coarse net stretched in the ring (fig. 16). Shark meat is normally fixed to the centre of the ring as bait. The traps are driven into the mud close to the mangroves. They are placed from a row boat at high tide and are pulled up after three or four hours. The clumsy crabs cling to the net when it is lifted out of the water.

Gill nets. Gill nets are not commonly used by the people of Ko Lao, because the coastal waters are shallow, but they are used along the coast of Had Sai Khao, where the water is deeper. The net is usually more than 100 m long, with a 7.5 to 10 cm mesh, and is operated from the shore. The catch consists mostly of pelagic fish. Swimming crabs (Portunus pelagicus) are often caught along with the fish.

Bag nets. Winged bag nets mounted across mangrove channels are found in both Ko Lao and Had Sai Khao and in adjacent areas, though this type of gear is not very popular because it cannot be moved. The net is lowered during high tide to trap the fish, which are harvested just before low tide. Many varieties of fish, shellfish, and other marine animals are captured.

Other fishing operations. Several minor fishing operations that are occasionally used include scoopnetting for jellyfish, gathering molluscs, and using single hooks, long lines, off-shore traps, and cast nets.

Jellyfish (coelenterates) are scooped from the surface of the water from motorized boats between October and December, using simple round scoop nets (fig. 17). The jellyfish are salted and dried before being sold to a middleman.

Some families in both villages gather Modiola, Anadara, Perna, limpets, and other edible molluscs for home consumption.

Only a few families from the two villages fish with single hooks or long lines. Long lines of about 50 to 100 m (fig. 18) are operated close to the mangrove edge, while single hooks are dangled from twigs or branches of mangrove trees. The catch usually consists of young grouper (Epinephalus tauvina), sea bass (Lates calcarifer), and other noneconomic fish.

One household of Ko Lao sometimes uses offshore traps for catching coral-reef fish such as Siganus and Epinephalus (fig. 19).

Only one household in Had Sai Khao uses a cast net. Shrimp is the major catch, but the catch from each operation is very small.

Composition of the Catch

As mentioned earlier, these traditional fishing methods are confined to the inshore and near-shore zones, so only juvenile or young stages of economic species are captured. The catch at Ko Lao and Had Sai Khao includes three major categories: fin fish, crustaceans, and molluscs. The species most commonly taken are similar in the two communities and are listed in table 11. The catch of penaeid shrimp is very small in Ko Lao, but because of the use of push nets in Had Sai Khao, shrimp are a major catch there.

Total Value of the Catch

In Ko Lao, fish are sun-dried and salted for sale, while Had Sai Khao people more commonly sell fresh fish (figs. 20 and 21).

Ko Lao. Fishing was the main occupation in 21 of the 26 households in Ko Lao (table 12). There were 11 households (42 per cent) that caught fish and small crustaceans; 8 (31 per cent) caught only small crustaceans; and 2 (8 per cent) harvested molluscs in addition to catching fish and small crustaceans. The other 5 households (19 per cent) probably fished only occasionally.

Small crustaceans, including mysids and Acetes, are plentiful in the water around Ko Lao. There were 24 households that gathered these crustaceans. Each household's total catch depends on the number of workers in the family, the number and size of nets used, and the duration of fishing. The annual catch for the different households varied from 270 to 2,000 kg, giving a total of 22,365 kg per year for the 24 operating households (or a mean of 932 kg per household). These small crustaceans are sold fresh or as shrimp paste, which is an important ingredient in South-East Asian cooking. To make the paste, the crustaceans are half-dried, ground with salt, then fermented, and dried again (fig. 22). Two kilograms of fresh crustaceans yield 1 kg of shrimp paste. The value of the catch, in terms of shrimp paste after processing, was about 456,006 baht (a mean of B 19,000 per household).*

TABLE 11. Species of marine animals commonly caught by Ko Lao and Had Sai Khao fishers

Local name Scientific name  
Fish kod ta-le Tachysurus con
krabok Mugil dussumeri
kao Epinephalus tauvina
krud-krad Pomadasys sp.
kang-lai Therapon jaboa
koak Anodontostoma sp.
juad Otholithes sp.
haang-kwai Thysanophrys sp.
krapong-khangpaan Lutianus sp.
krapong Lates calcarifer
salid-hin Siganus javers
krabane Dasyatis spp.
takrub Scathophagus argus
duk ta-le Plotosus lineatus
noalchan Chanos chanos
meow Engraulis spp.
kem ta-le Hemirhamphus sp.
Crustaceans kung khao Penaeus merguiensis
kung kula-dum Penaeus monodon
kung keoy Acetes sp.
poo ta-le Scylla serrate
poo ma Portunus pelagicus
kang tak-taan Squilla mantis
Molluscs hoi malang-poo Perna viridis
hoi kra-pong Modiola sp.
hoi krang Anadara sp.
hoi peak-pet [limpets]
hoi mhuk klouy Loligo sp.
hoi mhuk kradong Sepia sp.

There were 16 households in Ko Lao that engaged in catching fish - using long lines, gill nets, barrier nets, hooks, set bag nets, and other small gear. The fishing areas within one or two kilometres of Ko Lao are sand flats exposed during low tide. The total catch was about 11,280 kg, valued at B 215,164 per year (means of 705 kg and B 13,448 per household per year). Sale prices for the catch vary according to species of fish, size, and season.

Three households gathered crabs, using either crab traps, set bag nets, or gill nets. Scylla serrate and Portunus pelagicus are the economically important crabs of the area. They are usually caught close to the mangrove edge. The total catch was approximately 860 kg per year, valued at B 19,125 (means of 286.7 kg and B 6,375 per household per year).

Several families looked for additional sources of food for family consumption, including gathering molluscs of species commonly found on the mud-flats or diving for Modiola, Perna, and Anadara.

The total value of the economic species caught in Ko Lao was estimated at B 690,295 (B 456,006 for shrimp in the form of paste, B 215,164 for fish, and B 19,125 for crabs), giving an average income for the 26 households of this traditional fishing community of about B 26,550 per year, or B 2,212 per month.

TABLE 12. Households in Ko Lao catching various categories of aquatic animals

  Number of households
Buddhist Muslim Total %
Small crustaceans and fish 9 2 11 42.3
Small crustaceans only 3 5 8 30.8
Small crustaceans, fish, and
- 2 2 7.7
Small crustaceans and molluscs - 1 1 3.8
Small crustaceans and crabs - 1 1 3.8
Small crustaceans, fish, and crabs 1 - 1 3.8
Fish only - 1 1 3.8
Fish, penaeid shrimp, and crabs 1 - 1 3.8
Total 14 12 26 99.8

TABLE 13. Households in Had Sai Khao catching various categories of aquatic animals

  Number of
Fish, crabs, and molluscs 1 3.8
Fish, crabs, and shrimp 5 19.2
Fish and crabs 10 38.6
Fish and shrimp 3 11.5
Crabs and shrimp 2 7.7
Fish only 1 3.8
Crabs only 4 15.4
Total 26 100.0

Had Sai Khao. All 26 households in Had Sai Khao were engaged in catching fish, shrimp, molluscs, or crabs. There were 22 households that fished for crabs, 20 for fish, and 10 for shrimp (table 13).

The average catch per household per year was about 925 kg of fish, 452 kg of shrimp, 662 kg of crabs, and 4 kg of molluscs {table 14). Part of the catch was consumed at home and the rest was sold to the market (however, all molluscs gathered were consumed at home). Size influences the selling price. Prices for crabs vary less than those for fish or shrimp because the bigger crabs are usually selected for sale. The total annual sale of fish, shrimp, and crabs from the village of Had Sai Khao came to B 1,423,318. This yielded a moderately high average income per household of B 54,743 per year, or B 4,562 per month - derived more from shrimp than from fish or crabs (table 14).

Culture Fishery: Shrimp Farming

One attempt was made to culture shrimp at Ko Lao some years ago. The shrimp farm, which was located only five or ten metres inside the mangrove forest, was not successful because of poor management and location. The owner believed that he only had to construct the ponds and pump in tidal waters carrying shrimp seed, and that after one or two months the shrimp could be harvested. Shrimp-farm management is more complex. The location of a shrimp pond must be carefully selected, and physicochemical and biological factors need to be studied first. Primary productivity may be possible where an abundance of shrimp seed exist in coastal waters of high quality, but in ponds constructed in mangrove forest the texture of the soil is too loose for dike construction and cannot withstand the pressure of tidal water (fig. 23).


Socio-economic Conditions

General Features

Population origins. The present settlements of Ko Lao and Had Sai Khao were founded more than 23 years ago. Long before that the two village sites had been inhabited by a Muslim group of unknown origin, called chao nam in Thai, meaning fishermen. None of the people in the two villages seemed to know where this pioneer group came from or where they had gone.

The present population of Ko Lao moved there from the south, while the majority of the Had Sai Khao population came from central Thailand. This accounts for the different dialects spoken in the two villages; Ko Lao dwellers use a southern dialect or Malay, and those in Had Sai Khao speak Central Thai.

Reasons for migration to mangrove villages. The most common reason given by household heads in both Ko Lao and Had Sai Khao for migrating to the area was the attraction of the abundance of marine life and mangrove forest. Many were facing problems of population pressure and had less opportunity to earn an adequate income where they came from. They were looking for areas like Ko Lao and Had Sai Khao where there were still plenty of marine animals to catch.

TABLE 14. Average annual catch and income per household from aquatic animals - Had Sai Khao



Consumption (kg) Sale price (baht/kg) Income
Home Market Average Range  
Fish 924.8 92.1 832.7 30 20 - 50 18,078
Shrimp 452.3 72.7 379.6 70 40-80 24,105
Crabs 661.7 32.8 628.9 19 18-30 12,560
Molluscs 3.9 3 9 - - - -
Total 2,042.7 201.5 1,841.2     54,743

Among those not born in Ko Lao village, almost 91 per cent of the Buddhist respondents were cash-crop farmers before they moved to Ko Lao; none of them had been fishers. For the Muslims the previous occupation was predominantly fishing; about 29 per cent had been wage labourers, and 11 per cent were formerly orchard owners.

Reasons for migrating to Had Sai Khao are implied by the former occupations of the household heads. Prior to moving to Had Sai Khao, almost 62 per cent of the respondents had faced a shortage of farm land for growing rubber or other cash crops. About 38 per cent of respondents said they had moved to Had Sai Khao because they wanted to pursue a career in fishing.

Household size and composition. The Ko Lao households were larger on average (5.8 persons) than the Had Sai Khao households (4.6 persons) (table 15) and had a higher proportion of children (table 16), suggesting that Ko Lao families have a higher birth rate.

There was an average of 2.8 persons of working age (15-54 years) in each Ko Lao household, or about 48 per cent of the household members (table 15). The dependency ratio - i.e. the ratio of dependents (mostly children under age 15) to family members of working age - was about 1.07, meaning that each worker has to support one dependant in addition to him- or herself. The ratio was much higher in Muslim households (1.28) than in Buddhist households (0.86), principally because of the higher proportion of children in Muslim households.

In Had Sai Khao there were about 2.7 persons of working age per household, or 58 per cent of the population, and a dependency ratio of 0.72. The difference in dependency ratios suggests that Ko Lao households, especially the Muslim households, had a heavier burden of looking after their dependants than had the Had Sai Khao households.

Education. In order to increase the literacy of rural people, Thailand has for a long time had legislation requiring all children to enter primary school at age 7, and school attendance is now compulsory between the ages of 7 and 13, corresponding to the six primary grades. Despite this requirement, 23 per cent of the total population was illiterate in Ko Lao, and 17 per cent in Had Sai Khao (table 17). Fortunately, educational opportunities are better than in the past. There is now a primary school with six teachers in Ko Lao and one with five teachers in Had Sai Khao. Both schools offer education through grade 6. A relatively large proportion of the residents of both villages had completed grade 4 120 per cent in Ko Lao, 24 per cent in Had Sai Khao) and thus had acquired basic skills of literacy.

TABLE 15. Average numbers of all members and of members of working age in households in Ko Lao and Had Sai Khao, by sex and religion

  Number of
Number of
Persons per
Workers per
Ko Lao
Buddhist households 14      
males   41 2.9 1.4
females   37 2.6 1.6
total   78 5.6 3.0
Muslim households 12      
males   36 3.0 1.3
females   37 3.1 1.3
total   73 6.1 2.7
All households 26      
males   77 3.0 1.4
females   74 2.8 1.5
total   151 5.8 2.8
Had Sai Khao
All households 26      
males   58 2.2 1.3
females   61 2.3 1 .3
Total   119 4.6 2. 7

Slight discrepancies in the totals are due to rounding.
a. Household members between the ages of 15 and 54 years.

TABLE 16. Composition (percentages) of the population by age, sex, and religion

Age (years)

Ko Lao

Had Sai Khao




0 - 4 10.3 5.1 15.4 6.8 11.0 17.8 8.6 7.9 16.6 5.0 3.4 8.4
5-9 5.1 7.1 12.8 6.8 6.8 13.7 6.0 7.3 13.2 4.2 3.4 7.6
10 - 14 7.7 3.8 11.5 6.8 8.2 15.0 7.3 6.0 13.2 8.4 10.1 18.5
15-19 5.1 9.0 14.1 5.5 9.6 15.0 5.3 9.3 14.6 6.7 10.1 16.8
20- 24 5.1 2.6 7.7 6.8 2.7 9.6 6.0 2.6 8.6 4.2 3.4 7.6
25-29 2.6 1.3 3.8 4.1 4.1 8.2 3.3 2.6 6.0 4.2 2.5 6.7
30 - 34 3.8 3.8 7.7 1.4 1.4 2.7 2.6 2.6 5.3 1.7 1.7 3.4
35 - 39 3.8 2.6 6.4 1.4 1.4 2.7 2.6 2.0 4.6 2.5 3.4 5.9
40-44 0 1.3 1.3 2.7 1.4 4.1 1.3 1.3 2.6 3.4 3.4 6.7
45-49 3.8 1.3 5.1 0 0 0 2.0 0.7 2.6 3.4 1.7 5.0
50 - 54 1.3 6.4 7.7 0 1.4 1.4 0.7 4.0 4.6 2.5 3.4 5.9
55 - 59 1.3 1.3 2.6 5.5 1.4 6.8 3.3 1.3 4.6 0.8 1.7 2.5
60 - 64 2.6 0 2.6 0 0 0 1.3 0 1.3 0.8 0.8 1.7
65 - 69 0 0 0 1.4 1.4 2.7 0.7 0.7 1.3 0 0.8 0.8
70- 74 0 1.3 1.3 0 0 0 0 0.7 0.7 0.8 1.7 2.5
75+ 0 0 0 0 0 0 0 0 0 0 0 0
Total 52.6 47.5 100 49.3 50.7 100 51.0 49.0 100 48.7 51.3 100
Number of persons 41 37 78 36 37 73 77 74 151 58 61 119

Slight discrepancies in the totals are due to rounding.


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