4. Fishery characteristics

4.1 Fishery facilities in the bay of Phang-nga
4.2 Catch composition
4.3 Fishing effort and catch per unit effort
4.4 Income per unit effort
4.5 Expenditure and profit of Phang-nga bay fishermen
4.6 Net income per head and per day in a Phang-nga bay fishing household
4.7 Total profit earned in the Phang-nga bay with three types of gear
4.8 Total profit earned along the Andaman Sea coast with three types of gear
4.9 Total profit generated by small-scale fishery along the Andaman Sea coast
4.10 Total catch for three types of gear in the bay of Phang-nga
4.11 Total catch for three types of gear along the Andaman Sea coast

The description of small-scale fishery along the Andaman Sea coast is divided into 11 chapters. The first chapters describe the boats, the gear and the fishing grounds of the main gear types used and provide a well-documented overview of the catch composition, of the effort and of the catch per effort. Subsequent chapters analyse the income per unit effort, cost, profit made and total catch in the bay of Phang-nga and along the Andaman coast.

4.1 Fishery facilities in the bay of Phang-nga

The number of fishing boats classified by type of engine is shown in Table 11 for the bay of Phang-nga. The most commonly used boats are those with outboard engines (4446) followed by non-powered boats (705). Only 315 inboard-powered boats were enumerated in the bay. Numbering altogether 5151 (Table 11), the boats with or without outboard engine that are used in small-scale fishery represent about 94 percent of all boats in the bay of Phang-nga. Compared with 84.9 percent for the whole Andaman coast (Table 5), the percentage in the bay is 10 percent higher. The bay is home to 30.5 percent of all fishing boats with or without outboard engine used along the Andaman coast.

Table 11: Type of fishing boat in the Phang-nga bay, 1995

Boat	Phang-nga				Krabi		Phuket		Total
	Muang	Takua Thung	Thap Pud	Ko Yao	Muang	Ao Luk	Muang	Tha Lang
Inboard	2	1	-	175	58	16	46	17	315
Outboard	864	869	465	770	215	715	241	307	4446
No engine	143	153	100	65	63	123	-	58	705
Total	1009	1023	565	1010	336	854	287	382	5466

Table 12 shows the number of fishing boats in the six representative villages. This number varied between 14 and 430. Except for Laem Sak, the village with the highest number of fishing boats, no inboard-powered boats were found. In all six villages, the percentage of outboard-powered boats was over 95 percent. Only Hin Rom had five non-powered boats. The 679 small-scale fishing boats used as sample boats for this study comprised 13 percent of all small-scale fishing boats in the bay of Phang-nga or 4.7 percent of all small-scale fishing boats along the Andaman coast.

Table 12: Number and quality of fishing boats in the six representative fishing villages used for the collection of socio-economic data

Village	Inboard - powered	Percentage	Outboard - powered	Percentage	No engine	Percentage	Total
Ao Khung	-	0	14	100	-	0	14
Bang Chan	-	0	48	100	-	0	48
Hin Rom	-	0	115	95.8	5	4.2	120
Sam Chong Tai	-	0	40	100	-	0	40
Bang Pat	-	0	47	100	-	0	47
Laem Sak	20	4.6	410	95.4	-	0	430
Total	20		674		5		699

The various types of gear used in the bay of Phang-nga are shown in Table 13. The trammel net was the most common gear with 1723 units, followed by the grouper trap with 940 and the crab bottom gillnet with 699 units. The mackerel gillnet is listed as the fifth most commonly used gear, with 473 units. This reflects a situation similar to that shown in Table 6, with the exception of the mackerel gillnet, which differs from the type used outside the bay.

Table 13: Type and number of fishing gear used in the bay of Phang-nga (Anonymous 1995)

Fishing gear	Phang-nga				Krabi		Phuket		Total
	Muang	Takua Thung	Thap Pud	Ko Yao	Muang	Ao Luk	Muang	Tha Lang	[n]	[%]
Trammel net	338	365	-	469	69	417	31	34	1723	26.9
Grouper trap	288	118	252	133	17	96	6	30	940	7.4
Crab bottom gillnet	134	185	63	159	40	44	3	71	699	10.9
Crab lift net	128	140	95	8	19	129	-	47	566	3.7
Mackerel gillnet	63	144	10	21	29	190	-	16	473	4.2
Push net	124	46	143	14	15	51	-	15	408	14.7
Mullet gillnet	25	61	33	40	19	39	28	24	269	8.8
Whiting gillnet	26	11	2	98	4	12	74	10	237	0.8
Bamboo stake trap	15	145	-	5	13	13	-	37	228	0.9
Push net	44	9	40	12	15	41	26	39	226	6.4
Horse mussel scoop net	25	12	23	-	-	54	-	29	143	3.6
Anchovy purse seine	-	-	-	93	9	-	24	-	126	0.9
Cast net	-	21	2	9	17	6	2	2	59	2.2
Squid trap	-	-	-	22	14	-	1	20	57	2.0
Rock-fish bottom gillnet	5	2	-	15	5	5	14	8	54	3.5
Rays long line	-	-	6	13	1	27	5	-	52	0.5
Fish trap	-	-	-	22	-	-	18	3	43	0.7
Trawler	-	-	-	11	6	15	-	2	34	0.5
Squid luring light	-	-	-	-	31	-	-	-	31	0.8
Beach seine	6	1	8	-	-	14	-	-	29	0.5

The main types of gear used in the six representative villages along the bay of Phang-nga were the trammel net with 360 units, the mackerel gillnet with 198 and the crab bottom gillnet with 137 units (Table 14, overleaf). These gear types were among the five most frequently used in the bay of Phang-nga.

Table 14: Type and number of gear used in the six representative fishing villages for the collection of socio-economic data (Own data)

Gear	Ao Khung		Bang Chan		Hin Rom		Sam Chong Tai		Bang Pat		Laem Sak		Total
	[n]	%	[n]	%	[n]	%	[n]	%	[n]	%	[n]	%	[n]
Trammel net	8	18.6	2	4.3	74	44.3	6	7.2			270	53.3	360
Mackerel gillnet			1	2.1	42	25.1	4	4.8	1	2.7	150	29.6	198
Crab bottom gillnet	8	18.6	40	85.1	31	18.6	30	36.1	18	48.7	10	2	137
Whiting gillnet	3	7					2	2.4	8	21.6	10	2	23
Cast net	10	23.2					12	14.5					22
Mullet gillnet	2	4.7	1	2.1	3	1.8	3	3.6			12	2.4	21
Long line							1	1.2			15	3	16
Push net (by hand)							14	16.9					14
Pomfret gillnet											10	2	10
Fish trap					10	6							10
Other	12	27.9	3	6.4	7	4.2	11	13.3	10	27	29	5.7	72

The trammel net

The trammel net is a three-layered drift bottom gillnet. The outer layers are nylon multi-filaments with mesh sizes of 14 cm and the inner layer is a nylon monofilament with a mesh size of 3.8-4.2 cm. The length of the net is 24-30 m per piece and normally the fishermen use 20-35 nets per boat. The net can be used for two to three months and after that time, the lead and buoys can be reused to build a new net. The number of nets per boat differs in the three representative villages. Ao Kung villagers use 30-35 nets; Hin Rom fishermen use 20-25 nets whereas Laem Sak folk use 25-30 nets. Figure 2 indicates the main fishing areas of the three fishing villages investigated in the bay of Phang-nga.

Figure 2: The main fishing areas of the three representative fishing villages in the Phang-nga bay using the trammel net

The crab bottom gillnet

The crab bottom gillnet is a set bottom gillnet. It is a nylon monofilament with mesh sizes of 3-4.5 inches. The usual length of the net is 26-34 m, though in some villages it could be 100-m long depending on the environment. Each fisherman uses at most 25 to 85 nets and at least 20 to 25 nets. The net lasts for a couple of months and the fishermen change the net only. The total number of nets per boat in each representative village is 25-35 nets in Ao Khung, 80-85 nets in Bang Chan, 35-40 nets in Hin Rom, 30-35 nets in Sam Chong Tai and 20-25 nets in Bang Pat. In some other villages, only one piece of net is used. The net is used near the villages, and the main fishing areas of the chosen representative villages are close to the shoreline. Figure 3 shows the main fishing areas of the representative fishing villages for the crab bottom gillnet in the bay of Phang-nga.

Figure 3: The main fishing areas of the crab bottom gillnet of the representative fishing villages in Phang-nga bay

The mackerel gillnet

In the bay of Phang-nga two types of mackerel gillnet are in use, the first in the morning near the bottom with plastic buoys, the second in the evening in the mid-water near the surface with buoy No4. The net is made of nylon monofilament with mesh sizes of 4.3-4.7 cm. It is 100 m to 120 m long. One boat uses five to eight nets. Mackerel gillnet can be used for two to three years during the fishing season, from June to December. There is a closed season for mackerel from April until June. The length of the nets and number of nets per boat vary slightly in two villages investigated. Hin Rom uses five or six nets. which are 120 m long, and the total number of nets per boat is five or six. In Laem Sak, the fishermen use seven or eight 100 m long nets per boat. The type of mackerel gillnet used in the bay is not comparable with the gear used outside the bay.

Figure 4: The main fishing areas for the mackerel gillnet in the Phang-nga bay

4.2 Catch composition

The catch of small-scale fishermen in the bay of Phang-nga was investigated for the three main types of gear, namely trammel net, crab bottom gillnet and mackerel gillnet, used in the six representative fishing villages. Two approaches were used in this study to collect the needed information.

As presented in this section, the catch composition for each gear was determined by sampling. The whole catch was divided into species and species groups then weighed before the fishermen landed the catch.

The data used in the following sections was collected by middlemen and fishermen using logbooks. This method allowed the collection of more than a thousand data sets for some years, gear types and villages. Comparing the datasets of fishermen and middlemen checked the reliability of the data. Reportedly, the whole catch of shrimp was bought for personal consumption, so the weight of the shrimp was compared with the data in the logbook. During the establishment of the logbook system, several fishermen were excluded from the sampling routine because their data were not reliable.

The composition of the main target species for each village, each year and each of the three gear types investigated are shown in Tables 37 to 53 appended in annex. The crab bottom gillnet and the mackerel gillnet are highly selective, as demonstrated by high catches of the target species.

The trammel net is less selective. It catches mainly shrimp, i.e. Penaeus merguiensis followed by Metapenaeus spp. and Penaeus monodon. The main pelagics caught are Rastrelliger spp. and Sardinella sp. The catch also contained a certain amount of Pennahia anea. The catch composition per trip for the main shrimp, pelagic and demersal species during the monthly samplings in 1995 and 1996 is presented in Figure 5. In Laem Sak, the main shrimp species was Metapenaeus spp. The village has deeper fishing grounds and different seabed conditions.

The crab bottom gillnet was highly selective for crabs, in the bay of Phang-nga mainly for Portunus pelagicus. In some cases more than 90 percent of the total catch consisted of the target species. Besides, some rays, Dasyatis spp., and a few snails, Pila ampullacea, were also caught. The catch composition per trip during the sampling years for these species is shown in Figure 6.

The mackerel gillnet was used only in two villages. Catches were mostly Rastrelliger spp. There were also some Anodontostoma chacunda, Pennahia anea and Scomberomorus spp. caught with this gear. The catch composition per trip and per month in the sampling years 1995 and 1996 are shown in Figure 7.

Figure 5: Amount [g/trip] of the major target species or species groups, Penaeus merguiensis, Rastrelliger spp. and Pennahia anea in the trammel net sampled catches in 1995-96

Panaeus merguiensis

Rastrelliger spp.

Pennahia anea

Figure 6: Amount [g/trip] of the major target species or species groups, Portunus pelagicus, Dasyatis spp. and Pila ampullacea in the crab bottom gillnet sampled catches in 1995-96. The ordinates have different scales.

Portunus pelagicus

Dasyatis

Pila ampullacea

Figure 7: Amount [g/trip] of the major target species or species groups Rastrelliger spp., Scomberomorus spp., Pennahia anea and Anodontostoma chacunda in the mackerel gill net sampled catches in Hin Rom 1995-96

4.3 Fishing effort and catch per unit effort

Data for the fishing effort in fishing days per month and for the catch per unit effort were collected with logbooks provided to the fishermen and middlemen. This method may not be as accurate as direct collection but it did provide high numbers of samples, as many as 2151 for the catch per unit effort in Hin Rom in 1996 for the trammel net. Such high numbers allow for a good determination of the catch per unit effort, which can be used for further calculation and estimation of the total catch along the coast for the three gear types used in this study.

In the bay of Phang-nga the trammel net is used throughout the year. Outside the bay, fishermen cannot fish during the southwest monsoon, between May and September. The trammel net is the main gear used by Phang-nga bay fishermen. They use it in the nearshore area in front of their villages. The gear is lifted two to six times a day, at intervals of 15 to 120 minutes. In some villages the gear is also used twice per night during the dry season, with a lifting time interval of 120 minutes. The total fishing time depends on the fishing ground and on the current.

The fishing effort for the trammel net in 1995 and 1996 is presented in Figure 8 and Table 15. The effort varied between one fishing day per month in Laem Sak in November 1995 and 21 days per month for May 1995 and October and November 1996 in Hin Rom. Seasonal changes in the effort showed a slight increase between May and September in both years, except for Laem Sak (Figure 8). The low fishing effort for the trammel net in Laem Sak especially in the second half of the two investigated years was due to alternative seasonal fishing with mackerel gillnets. The average fishing effort for the trammel net was highest in Hin Rom, with 17 and 18 fishing days per month in 1995 and 1996 respectively. Ao Kung and Laem Sak showed similar average fishing efforts with 10 to 12 days per month.

Figure 8: Effort in fishing days per month for the trammel net sampled by logbook in three of the six representative fishing villages in 1995-96

Table 15: Fishing effort in the number of fishing days per gear for the trammel net in three of the six representative fishing villages in 1995-96

Village	Ao Kung		Hin Rom		Laem Sak
Year	1995	1996	1995	1996	1995	1996
January	14	12	14	18	13	11
February	9	8	17	16	11	11
March	10	9	13	14	16	13
April	10	11	16	17	11	11
May	11	13	21	16	18	10
June	13	15	19	17	19	14
July	15	12	18	20	8	11
August	13	10	19	20	3	8
September	11	12	18	18	14	6
October	11	12	17	21	3	12
November	14	11	17	21	1	4
December	11	8	16	19	15	11
Total	142	133	205	217	132	122
Average	11.83	11.08	17.088	18.08	11.00	10.17

The catch per unit effort for the trammel net is shown in Table 16 and Figure 9. It varied between 0.4 kg/day in Laem Sak in 1995 and 5.36 kg/day in Ao Kung in May 1995. The low catch per unit effort in Laem Sak is based on a single fishing day. In general, the catch per unit effort was rather low during the dry season, mainly February. March and April, and increased between May and August in both years.

Direct comparison of the catch per unit effort between the villages is difficult, because some villages, for example Hin Rom and Laem Sak, additionally used alternative gear like the mackerel gillnet. Fishermen used alternative gear if the target species caught did not provide them with sufficient income or fish distribution or if the tide allowed better catches using other types of gear. In general, the catch per unit effort per year for the trammel net varied roughly between 2 and 4 kg/day.

Table 16: Catch per unit effort in kg/day for the trammel net used in three of the six representative villages 1995-96

Village	Ao Kung		Hin Rom		Laem Sak
Year	1995	1996	1995	1996	1995	1996
January	4.05	3.11	2.14	2.49	2.68	1.80
February	3.38	2.56	2.02	2.63	1.58	2.62
March	2.91	2.57	2.24	2.15	1.80	1.67
April	3.45	2.28	2.55	2.11	1.59	1.60
May	5.36	2.94	2.76	2.30	2.46	2.10
June	5.26	3.62	4.29	3.42	2.46	1.86
July	4.01	4.02	4.22	3.12	1.69	1.50
August	3.42	3.14	4.06	2.84	2.93	0.68
September	3.11	3.06	3.33	3.15	3.93	2.75
October	2.90	2.79	2.55	2.55	2.90	1.61
November	2.72	2.48	2.90	2.33	0.40	3.15
December	2.68	2.31	2.60	2.23	2.08	2.54
Average	3.77	2.97	3.08	2.62	2.14	1.92
Sample [n]	365	257	1733	2151	590	528

Figure 9: Catch per unit effort for the main target species, Penaeus merguiensis, in kg per fishing day for trammel net sampled by logbook in five of the six representative fishing villages in 1995-96

The crab bottom gillnet was used at night and lifted only once. In some villages it was used only during neap tide as an additional gear, anchored with stones. When the crab bottom gillnet was the main fishing gear, a metal anchor was used.

Figure 10: Effort in fishing days per month for the crab bottom gillnet sampled by logbook in five of the six representative fishing villages in 1995-96

The fishing effort for the crab bottom gillnet is shown in Figure 10 and Table 17 for five villages. The effort in fishing days per gear varied between 2 days in Hin Rom and 20 days in Bang Pat. The average fishing effort per year was highest in Bang Pat, with about 13 days, followed by the villages of Bang Chan with 10 days, Sam Chong with 9 days, Ao Kung with 7 days and Hin Rom with 4 to 6 days for 1995-96. In general, the effort increased slightly between May and September in both years.

Table 17: Fishing effort in number of fishing days per gear for the crab bottom gillnet in five of the six representative fishing villages in 1995-96

Village	Ao Kung		Bang Chan		Hin Rom		Sam Chong Tai		Bang Pat
Year	1995	1996	1995	1996	1995	1996	1995	1996	1995	1996
January	9	10	14	13	6	5	14	9	14	15
February	7	5	10	8	5	2	9	5	13	15
March	6	4	6	9	2	5	8	3	13	9
April	5	5	5	11	8	11	10	7	14	7
May	9	10	14	9	6	4	8	11	7	19
June	11	7	6	11	6	5	9	10	18	15
July	9	9	11	15	10	4	12	11	17	17
August	10	8	16	13	9	4	12	7	10	10
September	9	9	9	9	5	4	6	11	12	6
October	8	3	6	8	8	4	10	12	5	14
November	5	5	14	8	5	6	5	10	13	12
December	4	4	10	9	4	3	8	8	18	20
Total	92	79	121	123	74	57	111	104	154	159
Average	7.67	6.58	10.08	10.25	6.17	4.75	9.25	8.67	12.83	13.25

The catch per unit effort for the crab bottom gillnet (Table 18, Figure 11) was 2.65 and 25.71 kg/day in Ao Kung in March 1996 and in Bang Pat in June 1995 respectively. The highest average catch per unit effort per year obtained for Bang Pat was 10.91 and 14.69 kg/day followed by Hin Rom with 8.09 and 11.65 kg/day. Bang Chan 9.31 and 10.72 kg/day, Sam Chong Tai 8.52 and 9.50 kg/day and Ao Kung with 6.02 and 8.04 kg/day, for 1995 and 1996 respectively. In both years the catch per unit effort increased during May-June until October.

Figure 11: Catch per unit effort for the main target species, Portunus pelagicus, in kg per fishing day for the crab bottom gillnet sampled by logbook in five of the six representative fishing villages in 1995-96

In Bang Chan, Sam Chong and Bang Pat the fishermen were largely dependent on the catch from the crab bottom gillnet whereas in Hin Rom they also used alternative gear.

Table 18: Catch per unit effort in kg/day for the crab bottom gillnet used in five of the six representative villages in 1995-96

Village	Ao Kung		Bang Chan		Hin Rom		Sam Chong Tai		Bang Pat
Year	1995	1996	1995	1996	1995	1996	1995	1996	1995	1996
January	5.54	4.19	8.17	11.21	3.55	8.42	6.37	7.55	13.22	10.24
February	6.20	5.47	7.56	8.68	3.57	8.30	5.88	3.04	10.80	10.65
March	8.33	2.65	9.49	3.72	1.90	6.55	4.82	6.72	11.83	7.73
April	8.61	8.16	12.19	9.23	6.65	6.69	5.04	5.12	10.54	7.33
May	8.96	7.55	8.01	10.28	11.14	7.43	11.28	7.48	11.35	10.82
June	8.43	5.82	12.88	8.01	14.59	12.25	13.56	8.34	25.71	13.23
July	8.94	6.47	13.27	12.04	11.10	7.36	10.99	14.02	21.57	13.16
August	9.07	7.46	13.15	8.54	16.50	6.38	10.86	9.05	16.84	15.76
September	7.81	7.30	11.75	15.06	9.98	7.89	10.39	8.98	13.36	10.78
October	8.46	4.50	13.20	9.13	10.02	10.36	10.52	12.80	12.23	8.52
November	8.31	3.16	6.11	8.97	8.13	4.13	7.89	9.04	11.78	8.93
December	4.46	2.73	5.70	4.91	9.38	3.64	8.26	5.83	11.94	6.93
Average	8.04	6.02	10.72	9.31	11.65	8.09	9.50	8.52	14.69	10.91
Sample [n]	256	136	378	241	384	208	337	233	511	342

The mackerel gillnet was used only in two of the six investigated villages between July and December to catch Rastrelliger spp of marketable size. The fishing grounds were not close to the villages.

In Laem Sak the highest fishing effort was found in November 1996, with 19 fishing days, whereas Hin Rom showed the highest effort in August 1995, with nine fishing days. The average effort over the fishing months was in Laem Sak, 9.33 and 12.8 days respectively in 1995 and 1996, and in Hin Rom: 6.5 and 6.33 days respectively. The effort for the mackerel gillnet (Table 19, Figure 12) in Hin Rom was low, because the fishermen used it as supplementary gear, shortly before and shortly after springtide. In Laem Sak it was the main fishing gear resulting in the higher fishing effort.

Table 19: Fishing effort in the number of fishing days per gear for the mackerel gillnet in two of the six representative fishing villages in 1995-96

Village	Hin Rom		Laem Sak
Year	1995	1996	1995	1996
July			3
August	9		12	18
September	8	5	14	8
October	7	8	13	14
November	2	6	9	19
December			5	5
Total	26	19	56	64
Average	6.5	6.33	9.33	12.8

Figure 12: Effort in fishing days per month for the mackerel gillnet sampled by logbook in two of the six representative fishing villages in 1995-96

The catch per unit effort for the mackerel gillnet (Table 20, Figure 13) showed for Laem Sak, which had an average of 77.75 and 76.35 kg/day in 1995 and 1996 respectively, the highest catch obtained in both villages. The catch per unit effort varied for Laem Sak between 17.7 and 138.1 kg/day in 1995 and between 30.3 and 111.21 kg/day in 1996. In Hin Rom it was found in 1995 to be 52.18 kg/day on average, with a maximum of 83.58 kg/day and a minimum of 30.85. In 1996 the average catch per unit effort was only 25.25 kg/day, with monthly variations of 21.78 to 29.23 kg/day.

Figure 13: Catch per unit effort for the main target species, Rastrelliger spp., in kg per fishing day for the mackerel gillnet sampled by logbook in two of the six representative fishing villages in 1995-96

Table 20: Catch per unit effort for the mackerel gillnet used in two of the six representative villages in 1995-96

Village	Hin Rom		Laem Sak
Year	1995	1996	1995	1996
July			17.67
August	83.58		138.10	111.21
September	52.65	24.75	103.59	30.30
October	30.85	29.23	111.70	101.80
November	41.63	21.78	63.35	38.05
December			32.10	100.40
Average	52.18	25.25	77.75	76.35
Sample [n]	173	154	209	145

4.4 Income per unit effort

The income per unit effort (IPUE) was computed based on data collected by middlemen in logbooks. This method of data collection ascertained the ways in which middlemen buy fish from fishermen. Some middlemen buy only the main target species separated by size or species or both; others lump shrimp or fish of different species or sizes together. The price is not fixed for a product and depends on the fisherman's indebtedness to the middleman. As most fishermen are Muslims, middlemen cannot charge interest rates on their loans but they compensate for this by paying lower prices for the catches.

At Ao Kung, the middlemen bought only the shrimp, i.e. Penaeus merguiensis and Penaeus semisulcatus, all sizes at the same price, from the catch of trammel nets. For Penaeus monodon they paid a higher price regardless of the size. The middlemen in Hin Rom bought P. merguiensis according to the size of the shrimp. The jumbo size had an average carapace length of 40.30 mm. with a range of 37.90 to 46.55 mm. and an average weight of 47.38 g per piece, with a range of 37 to 67 g. The medium size, which was mixed with P. semisulcatus had an average carapace length of 28.34 mm, with a range of 23 to 35.55 mm and weight of 18.18 g, with a range of 13 to 32 g. They bought P. monodon at the same price for all sizes and bought all sizes of Silago sihama. The middlemen in Laem Sak bought shrimp like in Hin Rom but also bought all other species like fish, crab, squid, and mantis shrimp.

The IPUE for the main target species Penaeus merguiensis for the trammel net is shown in Figure 14 and Table 21. The IPUE varied between Bt257 and Bt969 in Laem Sak in October and November respectively. The highest annual average IPUE was in Ao Kung at Bt605 followed by Laem Sak at Bt588 in 1995 and Bt546 in 1996. For Ao Kung and Laem Sak the average IPUE varied between Bt540 and Bt600; for Hin Rom it varied between Bt400 and Bt450.

Figure 14: Income per unit effort for the main target species Penaeus merguiensis in Baht per fishing day for the trammel net sampled by logbook in three of the six representative fishing villages in 1995-96

Table 21: Income per unit effort for the trammel net used in three of the six representative villages in 1995-96

Village	Ao Kung		Hin Rom		Laem Sak
Year	1995	1996	1995	1996	1995	1996
January	573.76	636.48	325.29	377.82	619.33	467.51
February	477.57	520.75	306.54	401.13	535.92	605.92
March	412.26	522.53	330.40	329.86	584.84	511.74
April	489.97	465.62	373.04	311.63	427.44	516.11
May	770.28	602.44	391.25	344.31	660.11	530.66
June	813.25	741.28	643.47	500.35	610.57	457.40
July	588.72	818.83	666.01	475.58	598.25	557.31
August	483.07	638.00	618.15	460.49	749.67	620.20
September	442.73	620.78	483.29	469.04	912.89	875.25
October	412.18	569.83	366.68	387.12	969.08	646.10
November	384.20	502.57	408.16	334.74	257.00	623.75
December	380.95	464.27	368.47	331.60	510.22	597.50
Average	545.21	605.07	454.23	395.52	588.59	546.14
Sample [n]	365	257	1733	2151	590	528

In the five villages using the crab bottom gillnet the middlemen bought all Portunus pelagicus. They also bought catfish but no data were available. The IPUE is shown in Figure 15 and Table 22. The lowest IPUE observed was Bt54 in Ao Kung in December 1996 and the highest in Bang Pat, Bt780 in June 1995. The average IPUE for the two investigated years varied widely, from up to Bt470 in Bang Pat to only Bt125 in Ao Kung in 1996.

Figure 15: Income per unit effort for the main target species Portunus pelagicus in Baht per fishing day for the crab bottom gillnet sampled by logbook in five of the six representative fishing villages in 1995-96

Table 22: Income per unit effort for the crab bottom gillnet used in five of the six representative villages in 1995-96

Village	Ao Kung		Bang Chan		Hin Rom		Sam Chong Tai		Bang Pat
Year	1995	1996	1995	1996	1995	1996	1995	1996	1995	1996
January	97.98	88.74	231.28	345.31	205.25	213.60	177.88	185.91	453.62	390.47
February	115.91	142.53	197.05	289.17	99.80	205.33	162.56	124.83	343.51	403.08
March	187.38	69.50	251.96	111.44	57.00	172.50	132.70	121.92	384.83	278.59
April	199.98	192.40	292.65	245.43	187.44	167.26	126.68	139.56	364.00	293.23
May	159.94	156.43	239.70	275.56	288.94	185.70	300.65	198.43	394.96	395.89
June	144.24	113.71	314.93	232.55	350.42	338.57	349.50	385.50	780.01	385.42
July	155.19	125.82	391.09	336.62	266.46	159.09	273.36	248.15	635.35	425.63
August	159.38	153.40	393.25	222.58	233.69	182.31	263.96	173.13	519.78	518.42
September	169.84	150.76	290.65	460.35	233.81	192.54	249.42	269.98	440.82	392.17
October	201.07	90.00	406.46	240.56	216.65	245.12	249.89	241.85	415.66	324.79
November	194.49	63.20	193.02	272.94	185.60	103.33	194.19	195.00	400.40	357.00
December	98.37	54.50	131.70	129.35	212.10	91.04	201.62	122.44	400.28	205.88
Average	158.27	125.73	295.91	266.98	245.48	205.37	238.86	210.13	470.97	377.38
Samples	256	136	378	241	384	208	337	233	511	342

The middlemen in Laem Sak bought the whole catch of the mackerel gillnet, including trash fish, crab and squid. In Hin Rom the middlemen bought only Rastrelliger spp., Scoboromorus spp., Anodontostoma chacanda and shrimp, i.e. P. merguiensis. Table 23 and Figure 16 give an overview of the observed IPUE for the two fishing villages using the mackerel gillnet. The highest IPUE was found in Laem Sak, with Bt1309 in August 1996; the lowest in Hin Rom, with Bt174 in November 1996. The average IPUE for the observed fishing months was Bt930 for Laem Sak in 1995 and 1996, but only Bt430 and Bt200 for Hin Rom in the same years.

Table 23: Income per unit effort for the mackerel gillnet used in two of the six representative villages in 1995-96

Village	Hin Rom		Laem Sak
Year	1995	1996	1995	1996
July			478.33
August	668.63		1133.12	1309.18
September	421.19	198.04	846.21	643.06
October	246.82	233.87	927.92	858.67
November	333.00	174.22	757.86	421.97
December			580.32	859.25
Average	427.49	204.73	931.84	935.18
Sample [n]	173	154	209	145

Figure 16: Income per unit effort for the main target species Rastrelliger spp. in Baht per fishing day for the mackerel gillnet sampled by logbook sin two of the six representative fishing villages in 1995-96

4.5 Expenditure and profit of Phang-nga bay fishermen

Tables 24 to 26 give an overview of the costs incurred from the fishing activities of the three types of gear used in this study. Table 24 presents the price of the gear, the average age and average fishing effort as well as the resulting cost per fishing effort. It was determined that the fishermen were able to recycle about 50 percent of the lead and buoys for the trammel net and the mackerel gillnet and about 90 percent for the crab bottom gillnet. The average fishing effort for each gear was calculated as the mean average fishing effort in the two years (Tables 15, 17 and 19).

Table 24: Cost per fishing effort in 1995-96, Part one: Gear cost

Gear	Complete gear [Bt]	Net only [Bt]	Percentage/Cost of gear recycled		Gear per trip [n]	Average age of gear [month]	Average fishing effort [day/month]	Cost per fishing effort with recycled net [Bt]
			[%]	[Bt]
Trammel net	413	220	50	96.5	25	2.5	13	243.5
Crab bottom gillnet	93	23	90	63	30	1.5	9	66.6
Mackerel gillnet	1456	690	50	383	6.5	3 years × 6 months	9	43

Table 25 presents the average age and cost for boat and engine and the resulting total cost per fishing day.

Table 25: Cost per fishing effort in 1995/96, Part two: Boat and engine per fishing day

Gear type	Boat 8-12 m [Bt]	Engine 5-12 hp [Bt]	Average age of boat [Month]	Average age of engine [Month]	Average fishing effort [Day/Month]	Cost per effort average boat and engine cost [Bt]
Trammel net	13500-21500	16200-24800	180	120	13	21
Crab bottom gillnet	13500-21500	16200-24800	180	120	9	30
Mackerel gillnet	13500-21500	16200-24800	180	120	9.5 (Six months only)	60

The additional cost for ice and fuel based on observation and interviews are presented in Table 26.

Table 26: Cost per fishing effort in 1995/96, Part three: Additional cost per fishing day

Gear	Fuel per day [Bt]	Ice per day [Bt]	Cost per effort [Bt]
Trammel net	30 - 50	5	45
Crab bottom gillnet	20 - 30	-	25
Mackerel gillnet	30 - 50	20	60

With the average income per fishing effort (Tables 21, 22 and 23), the resulting average profit per fisherman, fishing effort and gear was calculated in Table 27. The profit was highest for the mackerel gillnet, with Bt462, followed by the trammel net (Bt212.5) and the crab bottom gillnet (Bt138.4). When comparing these profits it has to be kept in mind that fishing mackerel can only be done six months a year.

Table 27: Profit per fishing effort for the three gear types used in the Phang-nga bay in 1995/96

Gear	Average income per effort [Bt/day]	Average cost per effort			Profit per fishing effort [Bt/day]
		Gear	Boat	Additional cost
		[Bt/day]
Trammel net	522	243.5	21	45	212.5
Crab bottom gillnet	260	66.6	30	25	138.4
Mackerel gillnet	625	43.0	60	60	462.0

No cost for the interest rates of debts is included in the calculation, because most fishermen are Muslims and it is not usual to pay interests in Muslim communities.

4.6 Net income per head and per day in a Phang-nga bay fishing household

Based on the calculated profit per fishing day (Table 27), the fishing effort in fishing days per month and the size of a fishing household (Table 4), the resulting net income per household per head and per day is presented in Table 28.

The calculation does not include the use of other than the main fishing gear, nor does it include other income-generating activities such as aquaculture, tourism, transportation or rubber gardening. The absolute amount of money available to each family member is thus higher. Nonetheless, the calculation being based on data from full-time fishermen using their main fishing gear, it gives a good idea of the amount of money available per head that is derived from the main fishing activity.

The total amount of money available per head and per day varied from Bt8.2 for the crab bottom gillnet and Bt18.1 for the trammel net (Table 28). Fishing with the mackerel gillnet, although done only six months a year, generated B13.7 per day per head. Based on these results, it is believed that the fishermen use alternative gear during the remaining six months.

Table 28: Net income per household and per head derived from fishing with the three gear types in 1995/96

Gear	Profit per fishing day [Bt]	Fishing days per month in Phang-nga bay [n]	Months of fishing [n]	Household members [n]	Net income per household available per day per year [Bt]	Net income per head available per day per year [Bt]
Trammel net	212.5	13	12	5	90.5	18.1
Crab bottom gillnet	138.4	9	12	5	41.0	8.2
Mackerel gillnet	462	9	6	5	68.4	13.7

These results show that a good combination of gear provided a relatively good income for the small-scale fishermen. The model calculations in Table 29 are given as an example of the combined use of the mackerel gillnet and trammel net. Such fishery can generate a daily income per head of up to Bt22.7 without increasing the observed average fishing effort per gear. This might explain why Hin Rom, where all three types of gear analysed are used, is more developed than the other villages.

Table 29: Model calculation of the yearly net income of a fisherman using the mackerel gillnet for six months and the trammel net for six months

Gear	Months used [n]	Average fishing effort per month [n]	Profit per fishing day [Bt]	Total net income per year [Bt]	Total net income per household per day [Bt]	Total net income per head per day [Bt]
Trammel net	6	13	212.5	16575	45.4	9.0
Mackerel gillnet	6	9	462	24948	68.4	13.7
Total				41523	113.7	22.7

Comparison of the net income of a fishing household (five household members) and the average total income of a household (3.67 household members) in the whole country (Table 30) shows that fishermen earn with their main fishing activity only about one fourth to one ninth of what the average household earns in Thailand. This underlines the importance of further assistance to small-scale fishermen.

Table 30: Net income per year and per household or head resulting from fishing with the main gear types in the Phang-nga bay compared with the average total annual income per household and per head in 1996 in Thailand (National Statistical Office 1998)

Gear	Amount per household available per day over the year [Bt]	Amount per head available per day over the year (5 persons/ household) [Bt]	Amount available per household per year [Bt]	Amount available per head per year (365 days/year) [Bt]	Average household annual income countrywide [Bt]	Average per capita annual income countrywide (3.67 persons/ household) [Bt]
Trammel net	90.8	18.1	33032.5	6606.5
Crab bottom gillnet	41.0	8.2	14947	2989	129348	35206
Mackerel gillnet	68.4	13.7	25002.5	5000.5

4.7 Total profit earned in the Phang-nga bay with three types of gear

Table 13 presents the total number of the three types of gear used in the bay of Phang-nga. Based on these data the total profit made with this gear was calculated on the assumption that the average catch in the six representative villages was comparable with the catch in the other villages of the bay. In Table 31, the total profit made in the bay was calculated based upon the average effort per month and the average profit already calculated (Table 27).

The total profit per year in the bay of Phang-nga under the given assumptions was of about Bt57 million for the trammel net, about Bt10.5 million for the crab bottom gillnet and about Bt12 million for the mackerel gillnet. For all gear, it amounted to about Bt79 million or about US$3 million (US$1 was equal to Bt26 in 1996).

Table 31: Total profit made in the Phang-nga bay with the three gear types in 1995/96

Gear	Establishments using such gear (Table 13) [n]	Profit per effort [Bt]	Effort per month [n]	Number of fishing months [n]	Total profit in the bay by gear per year [Bt]
Trammel net	1723	212.5	13	12	57117450
Crab bottom gillnet	699	138.4	9	12	10448093
Mackerel gillnet	473	461.9	9	6	11797849
Total					79363392

4.8 Total profit earned along the Andaman Sea coast with three types of gear

Table 6 presents the total number of establishments along the Andaman coast using the three types of gear. To calculate the total profit made with such gear, it has to be kept in mind that during the southwest monsoon fishermen outside the bay of Phang-nga cannot go out fishing with the trammel net and the number of fishing months is reduced to seven a year. Furthermore, it is assumed that the average catch per effort outside the bay is similar to the average catch per effort in the bay of Phang-nga. Under these assumptions, the total profit generated along the Andaman coast outside the bay of Phang-nga with the three gear types is presented in Table 32.

Table 32: Total profit made along the Andaman coast outside of the Phang-nga bay in 1995/96

Gear	Establishments using such gear (Tables 6. 13) [n]	Profit per effort [Bt]	Effort per month [Days]	Months of fishing [n]	Total profit outside the bay by gear per year [Bt]
Trammel net	1229	212.5	13	7	23765788
Crab bottom gillnet	812	138.4	9	12	12137126
Mackerel gillnet	Not used outside the bay
Total					35902914

The total profit generated outside the Phang-nga bay with the three types of gear was of approximately Bt36 million or US$1.4 million. The resulting total profit along the Andaman coast was Bt115 million or US$4.4 million (see also Table 31).

4.9 Total profit generated by small-scale fishery along the Andaman Sea coast

In calculating the total profit made in small-scale fishery along the Andaman coast, the following criteria were defined:

1. The above calculations show that small-scale fisherfolk are among the poorest of the coastal population. Nevertheless, there is a lower profit border that fishermen cannot cross without losing fishing as their main income-generating activity. This means that there is a minimum income generated by fishing activities that allows a fisherman to earn a livelihood for him and his family - the average fishing household described in Chapter 3.

2. The definition of small-scale fishing in Thailand is based on the gear used. Therefore, it is set that there is an upper profit border due to the equipment used. If a fisherman is able to buy and use commercial gear like seines or trawls he is no longer considered a small-scale fisherman. A very successful small-scale fisherman will automatically upgrade his status and become a commercial fisherman.

3. Small-scale fishermen have access to all kinds of small-scale fishing gear. They adjust to the local coastal situation and optimize their fishing activities to increase their income.

4. Based on the above settings of an income range between lower and upper profit borders and full access to all kinds of fishing gear, a very rough calculation of the total income generated by small-scale fishery along the Andaman coast can be made. To calculate the total profit, the average profit generated with the three different types of gear in the bay of Phang-nga is considered as the average profit made with all gear along the Andaman coast (Table 33).

Small-scale fishing households (Tables 3, 36) [n]	Average net income per day per fishing household for the 3 gear types (Table 28, average per household) [Bt]	Calculated total daily profit along the Andaman coast [Bt]	Calculated total annual profit along the Andaman coast [Bt]
15765	66.6	1050474.5	383423192.5
US$		40402.9	14747045.9

Based on the above given settings, the total profit generated by small-scale fishery along the Andaman coast is Bt383 million or about US$14.7 million.

The error of this approach increases if the calculated average profit of small-scale fishery is much higher or lower than the real average profit, which cannot be calculated, and if the fishermen have limited access to certain types of small-scale fishing gear and are unable to adjust to the most effective fishing practices in their area. This would translate into higher variations in the profit generated along the coast.

The second error does happen, apparently: only in two of the six representative villages did the fishermen go out fishing with the mackerel gillnet, which generates a relatively good income. On the other hand, fishermen using the crab gillnet may have used the trammel net as well to increase their income.

The error made using the average profit for the three gear types as the average income of all fishermen along the Andaman coast is due to the lack of alternative data in this field. Nevertheless, the calculated total profit gives a good idea of the economic importance of small-scale fishery along the Andaman coast.

4.10 Total catch for three types of gear in the bay of Phang-nga

The total catch in the bay of Phang-nga for the three types of gear was calculated as the product of the average fishing effort, the number of fishing months, the total number of gear and the average catch per unit effort, given that the catch for the three gear types is comparable in the whole bay.

For the trammel net the total catch in the bay of Phang-nga was 739 tons of shrimp, for the crab bottom gillnet it was 736 tons of crab, and about 1478 tons of mackerel for the mackerel gillnet (Table 34).

Table 34: Calculated total catch along the bay of Phang-nga in1995/96

Gear	Unit (Table 11) [n]	Average catch per unit effort [kg/day]	Average effort [day/month]	Months of fishing [n]	Total Phang-nga bay catch [ton]
Trammel net	1723	2.75	13	12	739
Crab bottom gillnet	699	9.75	9	12	736
Mackerel gillnet	473	57.88	9	6	1478

4.11 Total catch for three types of gear along the Andaman Sea coast

During the southwest monsoon (May to September), no trammel nets are used to fish outside the bay of Phang-nga. This was included in the calculation of the total catch along the whole Andaman coast. Therefore, the total catch outside the bay was calculated separately (Table 35) and the result added to the total catch from the Phang-nga bay.

Table 35: Total catch along the Andaman coast outside the Phang-nga bay in 1995/96

Gear	Unit [n]	Average catch per unit effort [kg/month]	Average effort [day/month]	Months of fishing [n]	Total catch along the Andaman coast [ton]
Trammel net	1.229	2.75	13	7	308
Crab bottom gillnet	812	9.75	9	12	855
Mackerel gillnet	Not available

Table 36 presents the total catch inside and outside the bay of Phang-nga and compares the resulting total catch in the Andaman Sea with official FAO data.

Table 36: Total catch along the Andaman coast for the three gear types in 1995/96 compared with FAO data (FAO 1998a)

Gear	Total catch in Phang-nga bay [ton]	Total catch outside Phang-nga bay [ton]	Total catch along the Andaman coast [ton]	1966 FAO statistics for main target species along Andaman coast [ton]	Percentage caught in small-scale fisheries [%]
Trammel net	739	308	1047	20020	5
Crab bottom gillnet	736	855	1591	11220	14
Mackerel gillnet	1478	NA	1478	227070	0.7

The total catch in 1995/96 for the trammel net was about 20000 tons of shrimp or about 5 percent of the FAO statistics, for the crab bottom gillnet 11220 tons or 14 percent, and for the mackerel gillnet 227070 tons or 0.7 percent.