BULETIN PERIKANAN FISHERIES BULLETIN
No. 68
DISTRIBUTION AND BIOLOGICAL STATUS OF THE PELAGIC RESOURCESOFFSARAWAK MALAYSIA
By Hadil Bin Rajali And Richard Rumpet Research Section Marine Fisheries Department Sarawak Bintawa, Kuching
{b,.c'
hutintt Pmy(" . ~
~.hfl4i~
DISTRIBUTION AND BIOLOGICAL STATUS OF THE PELAGIC RESOURCESOFFSARAWAK MALAYSIA
By Hadil Bin Rajah And Richard Rumpet Research Section Marine Fisheries Department Sarawak Bintawa, Kuching
DEPARTMENT OF FISHERIES MINISTRY OF AGRICULTURE MALAYSIA 1991
Ust of Figures Ust of Tables Ust of Plates Ust of Appendices ABSTRAK ABSTRACT I. INTRODUCTION 2.
MATERIAL AND METHODS
3. 4.
RESULTS DISCUSSION 4.1 Biological Status 4.2 Geographic Distribution of Habitat and Fishing Grounds of Majors Species Groups 4.2.1 . Tuna 4.2.2 Other Scombrids 4.2.3 Carangids 4.2.4 Clupeids 4.25 Others
S. CONCLUSION ACKNOWLEDGEMENT REFERENCES
Fig. I:
South China Sea Off Sarawak - Depths Distribution
Fig. 2:
South China Sea Off Sarawak - Species Distribution
Fig. 3:
Size composition of frigate tuna, Auxis lhazard caught by K.K. MANCHONG purse-seine in April, 1987 around a FAD very near to Terumbu Layang-Iayang (Swallow Reef).
Fig. 4:
Size composition of yellowfin tuna, Thttnnus albacares caught by trolling in waters off Terumbu Layang-Iayang during the April 1987 Trip.
16
Table 2: Summary of Regression of log Weight on log Length for ea(h species of fish .
J
Plate 2:
The caraitgids that are mostly caught by purse seine and here is mostly selar specifically Atule mate
18
Plate 3:
A bumper catch of Decapterus (Selayang) off Terumbu Layang-Iayang
Plate 4:
A good harvest of sardine by purse-seining carried out more towards the inshore waters
20
Plate 5:
Yellowfin (Thunnus albacares) caught by a longliner 5 NM off Terumbu Layang-Iayang
21
19
Pukat tunda, pukatjerut dan mengeret merupakan cara-cara penyampelan yang digunakan dalam kajian ini. Status biologi dan taburan geografi bagi kumpulan spesies utama ikan pelagik adalah didokumenkan. Ikan tuna neritik terdapat banyak di sekitar perairan terumbu-terumbu karang di laut Mukah dan Miri. Ikan tuna ini adalah bersaiz lebih kecil berbanding dengan spesies-spesies tUJla 'yellowfin' dan 'bigeye' yang terdapat di perairan laut dalam bahagian timur-laut Zon Ekonomik Eksklusif Sarawak. Ikan pelagik yang terdapat di perairan terumbuterumbu karang laut dalam seperti Terumbu Layang-layang adalah bersaiz lebih besar berbanding yang terdapat di perairan pantai. Sumber ikan pelagik yang terdapat di perairan laut China Selatan adalah bertaburan. Kumpulan-kumpulan ikan pelagik kecil didapati ban yak di kawasan perairan sedalam kurang daripada 60 m.
The bottom trawl net, purse-seine and troll line were used as sampling gears. The biological status,and the geographical distribution of the major pelagic species groups were documented. Neritic tuna were caught very near to atolls especially in waters off Mukah and Miri. These tuna are smaller in size when compared to the yellowfin and bigeye caught in the more open and deeper, oceanic waters of the north-eastern part-of Sarawak's Economic Exclusive Zone. Pelagic fish caught around deep sea reefs for example around Terumbu Layang-layang were of bigger size as compared to that caught in the shallow coastal waters. Pelagic resources of the South China Sea are scattered. Small pelagic schools occupied most of the waters of the shelf under 60 m deep.
The 1986 Malaysian Offshore Fisheries Resources Survey showed a substantial biomass of pelagic stock off Sarawak (over the Sunda Shelf) with particularly high density (8.3 tonnes/NM2). The total biomass for Sarawak was estimated at about 216,300 tonnes and of this, the potential yie1d is 108,150 tonnes (Fisheries Research Institute 1987, unpublished). The Fisheries Department Research Vessel, K.K. MAN CHONG was deployed in 1987 to do experimental surveys in the offshore waters (> 60 NM from the coastline) (Fig. 1). On several occasions, substantially large schools of pelagics were observed. Small pelagics such as the sardines, selar, Decapterus and other carangids were frequently encountered and caught mostly by purse-seine (Plate 1). Other pelagic fish such as tuna were either caught by the purse-seine or by the troll line. ~_Pelagic fish resources of the South China Sea are scattered. The installation of FADs (Fish Aggregating Devices) for example in waters off Terumbu Layang-layang archipelagos help to ~regate these scattered and low density pelagic fish resource of which tuna is the main component. The highly migratory nature of tuna makes this resource difficult to assess and the fish only stayed for a short while at the FADs possibly' in search of food. Other pelagics beside the tuna sampled at FADs in the Terumbu Layang-layang waters were mostly of mature size as compared to that sampled in the inshore waters (less than 60 NM from the coastline). This paper is based on K.K. MAN CHONG trips in 1987 carried out in Exclusive Economic Zone (EEZ) waters off the Sarawak coast. It is aimed to document the biological status and area distribution of the fish caught in the area surveyed.
The bottom trawl net (Appendix 1), purse-seine net (Appendix 2) and troll lines were used to sample the fish. Although the fishing operation could not give us the actual catch rates or densities, the survey revealed the nature and distribution pattern of pelagic resources in Sarawak waters. The position and the weight of individual haul were recorded. The catches were sorted and the fish species were identified based on SEAFDEC (1982) and Gloerfelt-Tarp and K~ilola (1982) manuals. The fish total length was measured to the nearest millimeter using a standard measuring board. The individual fish weight was measured to the nearest one gram using the top-pan weighing balance. The length-weight relationship was calculated using a PC-based Microstat statistical software.
Table 1 shows the catch landed comprising a large number of species. This species list gives an indication of the major commercial pelagic species found in Sarawak waters. A large percentage of the catch especially from trawling was trash fish. The size range of the commercial fish caught during the survey is shown in Table 2. Fish size varies considerably, and this could be due to the different area of catch, the partial un selective nature of the sampling gear (example purse-seine) and in some cases the number of sample (n) is too low.
Table I: Species of Pelagics Caught During K.K. MAN CHONG trips, 1987 names
Common
Scientific
Local names
names
Tuna
A. i)
Bonito/Skipjack
tuna
Tongkol
Katsuwonus
ii)
Longtaillbluefin
tuna
Aya hitam
Thunnus tong go I
iii)
Mackerel
iv)
Frigate mackerel
v)
Yellowfin
vi)
Bigeye
tuna/kawakawa
pelamis
Aya kurik
Euthynnus
Tongkol
Auxis thazard
tuna
affinis
Thunnus alhacares Thunnus ohesus
tuna
Small Pelagic Carangidae
B. i) ii)
Yellowtail
scad
Round Scad
Selar gelek
Atule mate
Selayang
Decapterus
macrosoma maruadsi
iii)
Round scad
Selayang
Decapterus
iv)
Rainbow
Pisang-pisang
Elagatis bipinnulatus
v) vi)
Hardtail scad Queenfish/Leatherskin
Cincaru Talang
Megalaspis cordyla Scomberoides tol
vii)
Ox-eye scad
Selar
Selar boops
viii)
Big-eye scad
Selar pucat
Selar crumenophthalmus
Selar kuning
Selaroides
ix) x)
runner
Yellowstripe
trevally
Horse mackerel
leptolepis
Caranx sexfasciatus
Clupeidae xi) xii) xiii)
Rainbow
sardine
Goldenstripe
sardinella
Spotted sardinella
Tamban bulat
Dussumieria
acuta
Tamban
Sardinella
gibbosa
Tamban beluru
Sardinella
sirm
Bawal hitam
Formio niger
Pelaling
Rastrelliger
brachysoma
Kembong
Rastrelliger
kanagurta
Tenggiri batang
Scomberomorus
Formionidae xiv)
Black pomfret Scombridae
xv)
Short-bodied
xvi)
Indian mackerel
xvii)
Narrow-barred mackerel
mackerel spanish
commerson
Table 2: Summary of Regression of Log Weight on Log Length for each species of fish
Species
Range in Length (cm)
Regression slope 'b'
Euthynnus affinis
24.5-53.5
3.1120
Katsuwonus pelamis
29.0-57.5
Thunnustonggol
Goodness Intercept 'a'
Regression offit r2
Number of Coeffici~nt r
. 0.01096
0.9706
0.9852
70
3.0486
0.01496
0.9710
0.9854
19
36.0-49.0
1.8873
0.97611
0.8080
0.9550
10
Auxis thazard
22.5-28.5
2.6574
0.04277
0.6623
0.8138
76
Thunnus alhacares
23.5-63.5
2.1808
0.4429
0.8781
0.9371
66
Elagatis hipinnulatus
42.6-94.0
2.6808
0.02468
0.9743
0.9871
21
Selar crumenophthalmus
15.4-28.6
2.9803
0.01378
0.9454
0.9723
94
Atule mate
20.5-25.8
2.3678
0.08525
0.6406
0.8004
55
Decapterus russelli
15.1-19. I
2.2239
0.09013
0.7489
0.8654
16
Decapterus macrosoma
13.5-36.5
2.9532
0.01 I 18
0.9684
0.9841
186
Raslrelliger kanagurla
23.4-26.4
4.4801
0.00008
0.7854
0.8862
13
Scomheromorus commerson
53.5-81.0
2.1555
0.21213
0.9532
0.9763
9
Sample n
Table 3: Size and area distribution Mean Length (cm)
Species
Range (cm)
Type
of pelagic species
General Area
Thunnus alba cares (Yellowfin)
40.8
23.5-83.0
Oceanic
100 miles offshore and more than 1000 m depth
Thunnus (Bigeye)
58.4
58.0-59.0
Oceanic
- same -
Auxis thazard (Frigate)
27.6
22.5-28.5
Neritic
Around atolls
Thunnus tonggol (Longtail tuna)
42.8
36.0-49.0
Neritic
10 nautical miles offshore and around atolls
Euthynnus affinis (kawakawa)
30.5
24.5-53.5
Neritic
- same -
Katsuwonus (Skipjack)
pelamis
37.6
29.0-57.5
Neritic
30 miles offshore
Rastrelliger
kanagurta
25.7
23.4-26.4
obesus
Rastrelliger brachysoma Decapterus
Shallower,
less than 60 m d
- same russelli
16.9
15.1-19.1
Distribution over the Shelf between 50 miles offshore
Selar crumenophthalmus
24.9
21.3-26.3
- same -
Scomberomorus commerson
65.6
58.5-86.0
Shallow areas
A generalised area distribution of major pelagic fish is shown by Figure 2 and Table 3. Most of the tuna species were caught in waters more than 60 m deep. Small pelagic fish like the carangids and the mackerels were caught in shallower waters.
The fish sampled vary in size and the different area of catch, partial selectivity of the gears used and insufficient number of samples were suspected to be the contributing factors. This survey showed that different area of sampling caused variation in fish size distribution. For Euthynnus affinis, there were three main areas of catch: around Terumbu Layang-Iayang, Luconia Shoals and west of Muara Tebas. Fish caught in area around Terumbu Layang-Iayang were smaller in size (mean size of 26.73 cm) when compared to fish caught in areas West of Muara Tebas with mean size of 39.8 cm and Luconia Shoals with mean size 51.5 cm. Katsuwonus pelamis were caught in areas around Terumbu Layang-Iayang and FAD station I (tat. 03° 56.2'N, Long. 110° 08.7'E). The mean size of skipjack found in Terumbu Layang-Iayang waters is 38.1 cm. In FAD station 1 the mean size is 47.7 cm. A tail of Katsuwonus pelamis was caught in Luconia Shoals and it measures 57.5 cm in length. The mean size of Thunnus tonggol caught is 42.8 cm and the areas of catch were Lydie Shoals (Beting Mukah) and FAD station 1. The fish caught in these areas is similar in size to that caught in West Malaysia (lPTP, 1986b). According to Klinmuang (1978 and 1981) and Cheunpan (1984) the smallest sexually mature female skipjack determined from the Gulf of Thailand was 34.2 cm long so the longtail tuna caught around Lydie Shoal and FAD stations could be matured too. However, Chiampreecha (1978) mentioned that females in the 31 - 47 cm interval were mostly immature. Klinmuang (1978) suggested that females in the 45 - 50 cm interval could be matured as the case in the Gulf of Thailand. Both Auxis thazard and Thunnus albacares were caught in areas of Terumbu Layang-layang and the mean size are 27.6 cm and 40.8 cm respectively. Figures 3 and 4 show the length frequency distribution of the fishes respectively. The saiz of rainbow runner, Elagatis bipinnulatus, caught in areas around James Shoal (Beting Serupai) is smaller (mean size of 51.5 cm) compared to that caught in Terumbu Layang-Iayang waters (mean size of 84.6 cm). Rainbow runners caught were mostly of mature size since the first maturity is 13.0 cm long according to Ingles and Pauly (1984) for that of the Philippines waters.
In the area north of Sematan (Lat. around position (Lat. 03° 59.29'N, crumenophthalmus is 24.9 cm. Most first maturity stage which is around for Gulf of Thailand).
02° 19.48'N, Long. 109° 53.01 'E) and Long. 112° 15.71 'E), the mean size of of the selar caught have already attained 19.4 (Department of Fisheries, Thailand
areas Selar their 1984,
Atule mate which were caught in areas north of Sematan (Lat. 02° 11.40'N, Long. 110° 05.87'E) have mean size of 22.9 cm. According to Aglen et al., (1981), the size of Atule mate caught has approximately attained full growth size (Plate 2),
where the maximum Malacca.
body size ever captured
is only 28.0 cm in the Straits of
Decapterus russelli was found to have mean size of 16.9 cm. Magnusson (1970), Tiews et al., (1970), Ronquillo (1974) and Ingles and Pauly (1984) mentioned that this scad attained its first maturity length at 16.6 cm for Palawan waters. The two areas ot catch for Decapterus macrosoma were in areas around Terumbu Layang-Iayang and north of Sematan (Lat. 02° 12.40'N, Long 110° 05.87'E). The size of the scad caught in these areas are 31.7 cm and 17.1 cm respectively. The round scad caught around Terumbu Layang-Iayang were of big size (Plate 3) as compared to maximum size captured, 25.0 cm for Manila Bay and Palawan waters (Magnusson 1970; Tiews et al., 1970; Ronquillo 1974) and 25.4 cm for Java Sea (Dwiponggo and Pauly 1986 c.i. Chullasorn and Martosubroto 1986). Length at first maturity is at about 16.5cm as reported by Chullasorn and Martosubroto (1986). Rastrelliger kanagurta and Scomheromorus commerson caught have a mean size of 25.7 cm and 65.6 cm respectively. Size at first maturity for R. kanagurta from the Straits of Malacca is 18.75cm (Pathansali 1961, 1967 and Chee 1980). According to Chullasorn et al., (1973); and Suponggon and Chayokwi (1979) for Gulf of Thailand, size at first maturity for S. commerson is 58.6 cm. 4.2
Geographic Distribution Major Species Groups
of Habitat
and Fishing Grounds
of
The prevalence of oceanic conditions for waters around Terumbu Layanglayang suited the presence of highly migratory oceanic tunas like yellowfin (Thunnus albacares) and bigeye (Thunnus ohesus). Furthermore, according to Marquez (1977) and Boonragsa (1987), larva of yellowfin were found to be present in Terumbu Layang-Iayang waters and that of bigeye were sampled in waters at about 100 NM off Bintulu around Luconia Shoals. As observed by K.K. MANCHONG, most of the tunas in Sarawak waters migrated close to the reef areas where the water current is irregular and swift. The deep sea FAD pilot project conducted by the Department of Fisheries in Terumbu Layang-Iayang waters enabled K.K. MAN CHONG to carry out two monitoring surveys in 1987. At the FADs (set in April, 1987) sited nearer to the oceanic trench with depth of about 1000 metres or more, yellowfin and bigeye tunas were observed to aggregate for sometime. In the earlier part of the survey (June, 1987) most of the yellowfin and bigeye tunas caught by trolling and purse seining comprised immature tuna of the size range of 3-5 kg. per tail. But in the second monitoring trip (September 1987), large schools were observed through the sonar and echo sounder at a depth of more than 60 meters. Probably large tunas are aggregating at the deeper zone. The catch of large tuna by a longliner (Plate 5) proved that large tuna do exist in the Terumbu Layang-Iayang waters. Oceanic tuna resource is difficult to access due to
its highly migratory nature. Tuna stayed at FADs for only a short while and probably when food are scarce they move away. The neritic tuna with species like frigate tuna (Auxis thazard), longtail tuna (Thunnus tonggol) and kawakawa (Euthynnus affinis) were also caught in Terumbu Layang-layang waters in areas nearer to the atoll or at FAD set near the Luconia Shoals. Skipjack (Katsuwonus pelamis) were also found in Terumbu Layang-layang waters. Most of the oceanic or neritic tuna in Terumbu Layang-Iayang waters form their own school separately. Yellowfin tuna (mostly juvenile) were found to form a school together with skipjack. This is probably because skipjack and juvenile yellowfin tuna were of the same physical size and tend to have similar behaviour (Masterfisherman Yoshibumi Kihara 1987 - personal communication). It has been known that mature yellowfin form their own school, but this could not be confirmed during K.K. MANCHONG FAD monitoring trip to Terumbu Layang-layang (Kihara, 1988). Small tuna were observed along the coastal water belt (more than 10 nautical miles offshore) in areas like off Tanjung Sirik and Tanjung Datuk and in waters of Lydie Shoal and Luconia Shoals. Lydie Shoal was observed to be the most popular habitat for neritic tuna. Chen and Wei (1981) reported that larvae of longtail tuna have been collected in South China Sea. This observation was also mentioned by Chullasorn and Martosubroto (1986), where areas off Lydie Shoal were found to be the spawning ground for this coastal tuna. Market landings (Marine Fisheries Department Sarawak 1987) showed that Mukah contributed more than 50% with Miri about 30%. The Miri tuna landings comprised of 50% kawakawa. 25% frigate tuna, 20% longtail tuna and about 5% skipjack. In the area off Miri where the outer edge of Sunda Shelf is only about 30 nautical miles out and nearer to the Pacific Ocean (Fig. 1) the influence of high saline-deep waters attracts the presence of skipjack to this north-eastern part of Sarawak waters.
The Indian mackerel and Spanish mackerel were mostly caught in shallower (less than 60 m deep) coastal waters off Sarawak. This was also mentioned by Menasveta et al., (1973). The Indian mackerel (Rastrelliger spp.) were usually caught by purse seine with the aid of light. Once the fish was attracted to the light, the school stayed for @out two hours, after which the school reduced in size and move to some other areas possibly in search of food. Two species of Rastrelliger found in Sarawak namely Rastrelliger kanagurta and R. brachysoma. R. kanagurta were found to be more abundant off-shore. This was also confirmed by Druzhinin (1970). There were two species of Spanish mackerel namely Scomberomorus commerson and S. guttatus with the former bigger in size (58.5-86.0 cm). These two species of Spanish mackerel were usually found in the same school. This barred Spanish mackerel can also be found in shallow undulating coral areas like Lydie Shoal, Parons Shoal, James Shoal and caught usually by handline.
Most of the carangids were caught by purse seine (using light as attractant) and occasionally by trawl or trolling. Small carangids like selar (S. crumenophthalmus and Atule mate), hard-tail scad (Megalaspis cordyla), round scad (Decapterus maruadsi) were distributed all over the shelf in the coastal waters stretching to 50 NM offshore. Bigger carangids like rainbow runner (Elagatis hipinnulatus) and hard tail scad were distributed around reef waters like James Shoal, Lydie Shoal and Luconia Shoals. Other bigger carangids like trevally (Selaroides leptolepis and Caranx sexfasciatus) and queenfish (Scomheroides tol) were mostly caught in shallow coastal waters near coral areas like off Sematan and off Mukah. Bigger and mature size carangids (23.5-36.3 cm) for example Decapterus macrosoma were caught in deep waters of Terumbu Layang-Iayang, whereas the smaller size Decapterus (\ 3.5 - 18.6cm) were found to inhabit the shallower coastal waters for example off Sematan.
Most of the c1upeids were small pelagics of the sardines (tamban) species namely: rainbow sardine (Dussumiera acuta), goldenstripe sardinella (S. gihhosa) (Plate 4) and spotted sardinella (S. sirm). The sardines were caught mostly in inshore waters (less than 60 m deep) along the coastal belt of Sarawak from Tg. Datuk to Brunei Bay. The sardines were attracted by florescent light especially during the dark-phase of the moon. But as the light was shown for more than 3 hours, the fish school were reduced to a smaller mass, probably due to the absence of food.
The triggerfish of the species Canthidermis maculatus were observed to be abundant around the 20 FADs set in the offshore waters (\ 00 - 150 NM off Kuching). When the aggregating materials (palm leaves) of the FADs were rotten after about five months, Ahalistes were observed to aggregate around the area. Ahalistes were also mentioned to be confined largely in the area where the depth range is 50 to 90 m (Fisheries Research Institute 1987) .. This fish is of low commercial value in the local market. Other fishes found aggregating around the FADs were carangids, rainbow runner, Seriola rivoliana and Coryphaenidae (dolfinfish) of species Coryphaena hippurus. Through diving, it was estimated that about 10 to 100 kg of these fishes were observed to aggregate around the FAD (Kihara 1988).
The density of pelagic fish over certain areas vary with season. During the calm offmonsoon season (April-September), it was suggested that there is an inshore movement of pelagics whereas during the monsoon (October-March) offshore migration and dispersion prevailed (Fisheries Research Institute, 1987). This phenomenon was also observed by K.K. MANCHONG.
mostly in the inshore waters (15-30 m depth) during the onset of the monsoon in the months of September and October. Larger pelagics like neritic tuna and few carangids were observed to occur in the 50-60 m depth zone. This distribution pattern of pelagic fish seemed to stretch all the way along the inshore waters off Sarawak. This observation was in accordance to that shown by Malaysian EEZ survey, 1986 (Fisheries Research Institute, 1987). Tuna resources were confined to the high saline water around the reefs like South and North Luconia Shoals, Terumbu Layang-layang and other atolls which are more than 60 NM from the coastline of Sarawak. Basically, shoals of pelagic fish were scattered and small in size. The western part of Batang Lupar Basin (inshore water) is a potential area for pelagic fishery. This was also mentioned as one of the three high density areas from the Malaysian EEZ Survey, 1986 (Fisheries Research Institute, 1987).
The authors wish to convey their sincere gratitude to the Director-General of Fisheries Malaysia, Y. Bhg. Dato' Shahrom b. Hj. Abd. Majid, Director of Marine Fisheries Department Sarawak (MFDS), Mr. Teo Chee K wang and the Director of Fisheries Research Institute Malaysia Mr. Ong Kah Sin for their encouragement and invaluable support in carrying out this work. A debt of gratitude is also due to Mr. George Chong Chiaw Min (Head of Research Section MFDS) and Mr. Albert Chuan Gambang for their critical comments on this presentation. Appreciation also goes to Mdm. Annie Lim PK, Puan Dayang Mariayani and En. Peter Tingkau for processing the data and finally typing the report. Last but not least to unspecified assistants, those who have rendered their help directly or indirectly towards the preparation of this paper.
Aglen, A., Foyn, L., Godo, O.R., Myklevoll and Ostvedt, OJ. (1981) Surveys of the Marine Fish Resources of Peninsular Malaysia, June-July 1980. Report on surveys with the R/ V Dr Fridtjof Nansen. Bergen, Institute of Marine Research, 70p. Boonragsa, V. (1987) Tuna resources in the Thai waters, Andaman Sea. In: Collective Volume of Working Documents presents at the "Expert Consultation on Stock Assessment of Tunas in the Indian Ocean", Colombo, Sri Lanka, 4-8 December 1986. Indo-Pacific Tuna Development and Management Programme, 267-280. Chee, P.E. (1980) The reproductive pattern of Rastrelliger kanagurta. In Proceedings of the second Annual Seminar. Kuala Lumpur, Malaysian Society of Marine Science, pp. 3344. Chen, Z., and S. Wei (1981) An investigation on the distribution central region of Nan Hili. J. Fish. China, 5(1}: 41-47.
of tuna fish larvae in the
Cheunpan, A. (1984) Sexual maturity, size at first maturity and spawning season of longtail tuna (T. tonggol), eastern little tuna (E. affinis) and frigate mackerel (A. thazard) in the Gulf of Thailand. Tech. Rep. Pelagic Fish Sub-Diy. Mar. FishDiv., Bangkok (4): 25p. Chiampreecha, B. (1978) Biological studies on tuna and tuna-like fishes in the west coast of the Gulf of Thailand and off east coast of Peninsular Malaysia. Tech. Rep. Pelagic Fish. Unit. Mar. Fish. Div., Bangkok (4): 25p. Chullasorn A. and P. Martosubroto (1986) Distribution and important biological features of coastal fish resources in Southeast Asia._FAO Fisheries Technical Paper 278 FAO Chullasorn, S., K. Chotiyaputta and Chayakul (1973) Preliminary studies on the narrow-barred Spanish mackerel Scomberomorus commerson (Lacepede, 1802) in the Gulf of Thailand. Tech. Rep. Pelagic Fish. Unit Fish. Div. Bangkok, (1973): 47p (in Thai). Department of Fisheries Thailand (1984) Purse seine fisheries and the present status of pelagic fish resources in the Gulf of Thailand. Paper presented to the Marine Fisheries Seminar, Bangkok, 4-7 September 1984, 68p. (Mimeo in Thai)
Department of Marine Fisheries Sarawak (1987) Annual Report 1987, Ministry of Agriculture, Malaysia. Druzhinin, A.L. (1970) Indian mackerel, Rastrelliger Fish. Counc., 13(2): 59-81
spp, in Burma Waters. Proc. Indo-Pac.
Fisheries Research Institute (1987) Offshore Fisheries Resources Survey within the Malaysian Exclusive Economic Zone. Ibupejabat Perikanan, Kementerian Pertanian Malaysia, Vol. 1 Mimeo: 19p Fisheries Research Institute (1987) Offshore Fisheries Resour~es Survey within the Malaysian Exclusive Economic Zone. Ibupejabat Perikanan, Kementerian Pertanian Malaysia, Vol. 2 Bk. I Mimeo: 101p Gloerfelt-Tarp, T. and Kailola, PJ. (1982) Trawl Fishes of Southern Indonesian western Australia. Australian development Assistant Bureau. Directorate Fisheries, Indonesia. German Agency for Technical Cooperation. Ingles, J. and D. Pauly (1984) An atlas of the growth, mortality and recruitment fishes. ICLARM Tech. Pap., (13): 127p
and NorthGeneral of
of Philippines
IPTP (Indo-Pacific Tuna Development and Management Programme) (1986b) Report of the meeting of Tuna Research Groups in the south-east Asian Region. Indo-Pacific Tuna Development and Management Programme IPTP/86/GEN/1O' 75p. Kihara, Y. (1988) Final Consultant Report - Masterfisherman Fisheries Department Sarawak. Mimeo: 27p
1988. Research Section, Marine
Klinmuang, H. (1978) Preliminary studies on the biology of tunas in the west of the Gulf of Thailand and off the east coast of Peninsular Malaysia. Tech. Rep. Pelagic Fish Unit. Mar. Fish. Div., Bangkok (1978): 27p Klinmuang, H. (1981) Length frequency distribution and length-weight relationship of tunas in the Gulf of Thailand. Tech. Rep. Pelagic Fish Unit. Mar. Fish. Div., Bangkok (24): 33p Magnusson, J. (1970) Report on assignment as marine biologist with the UNDP(SF)/FAO Deep-Sea Fishing Development Project in the Philippines (January 1966-June 1969). Rome, FAD UNFP/SF Project PH/llI: 90p Menasveta, D., S. Shindo and S. Chullasorn (1973) Pelagic fishery resources of the South China Sea and prospects for their development, Rome, FAO, South China Sea Fisheries Development and Coordinating Programme, SCS/DEV /73/6: 68p Murdoch, J, and Barnes J.A. (1982) Statistical tables for Science, Engineering, and Business studies. Second Edition. The Macmillan Press Ltd. 20 Pathansali, D. (1961l A preliminary report on the Rastrelliger 2(2): 37-45 Pathansali, D. (1967) Observation on the gonad kanagurta Cuvier. Proc. IPFC, 12(2): 112-5
maturity
Management
fishery in Malaysia. Proc. IPFC,
stages of female
Rastrelliger
Ronquillo, LA. (1974) A review of the round 15(3): 351-75
scad fishery in the Philippines.
Proc.lPFC,
Sakurai, T. and M. Miyake (1987) Manual for collecting statistics and sampling on tuna and tuna-like species in the Indian Ocean and Southeast Asian Region. Indo-Pacific Tuna Development and Management Programme (lPTP). SEAFDEC (South-East Asian Fisheries Development Centre) (1982) A colour guide to the Fishes of the South China Sea and the Andaman Sea. Primary Production Department/ Marine Fisheries Research Department, SEAFDEC, Singapore. Supongpan, S. and R. Chaayakul (1979) Population bionomics of the Spanish mackerel, Scomberomorus commerson (Lacepede, 1802) in the Gulf of Thailand. Tech. Rep. Pelagic Fish. Unit Mar. Fish. Div. Bangkok, (9): 31p Tiews, K., LA. Ronquillo and P. Caces-Borja (1970) On the biology of round scads, Decapterus Bleeker in the Philippines waters. Proc,.IPFC, 13(2): 82-106 Yesaki, M. (1987) Synopsis of Biological Data on longtail tuna, Thunnus tonggol. Indo-Pacific Tuna Development and Management Programme (IPTP).
.
I I
~':'<:~::'~[.~>" ....... ". en' . "'1': ..~ 1-
Terumbu Layang-Layang ,.•- r'-.1
/
/./(,....
....
" ......... ?'~.>: / './;
...~·:u)O...f.tm ... N. Luconi a shoals ..•.• ...••.. ..••.. ....... ;::
)
\>-
......."\
/'
..
~(1J..r~
CHI
1._~ •••
I
\.
;"JU
r....·
.... F·.... (
,Ii I
Bt9 .L'~ ...~
'ata~··..·..···.B.aI.;·i n
Kuc ng.
/
--'
J ! f~··/··~ ..··..,,,.j. I' ...... .Datu
ft;>o.. /.....
~.J
{
!.,
5 E A "p.,
,.-._,,,,-:Beting
i
i
NA
.••
Si
••j"
/"
,••••
•.•.. ...."/ ..I.J :"if ,...' .. ,-j ... ;'. ) S. Luconl-.;l stlOa:}'S'.....:./ ..,/ j'".,•.......... 7 .' ..' I 50·-f-till ' ...- - __ .....•.. -."" ,I r ..........•...... / .. ./' '.... ..,/ , ~l:.:~·.".. " ,...............,.,
f. .;}
,1
,.' f" .....
•.' •.-
•••, •••
:
.-d·..· _..//~
./,1 _/ ./''/
.","''' ••• J"
__
.....•
Serupai./ Beti ng Tugarr' Beti ng MUk.~~ / .... lO...f-tm·.....
:~/,/ I
.
\.
/
f
/.
,....
.I
1"
(
,/
"\I,.V~
I
1/
,"
,,/ ,"
I
,
I'
,I
," ,,' '
,
,"
.•.•.•'"
.: .'
.•.• .•
Thunnus albacar..q·' Thunnus obeso's)
---~
,"
I'· I'.
",' .. "-
D~~ter(us
I
I \
""
\
\
../'
...... _ .... - ....
I
I
,
.
.--I .•.•
J'~
I I I
,, I
,
I
I
I I I
..I I I
,
I
.
,
I I
I I I
.
,
,,.. I I I
,
, I
j ..•...
-,
.' ··....f ") Clupeids Trev\,ll.ifiS I lIega-iaspi:.!i...tordy la r~nnus ton~ i uthynnus affinis Selar
cru.e
i~elliget .......... ./ R. brachys~. o;;capteru(
s.•
ate
/
... .
'ptn~i gurta
. \
I
I
...
Auxis t~a~llr:Jl.' /. Katsuwanu~' pel~.is Mh~:;;t"'i'(finis
,"
.~"
),. ~ •..
,,'
i::/-···,·/'t!(;J
I
nc,..os· .
..../".) ..
("
... '
.I ;
,
...../
! .
';! {....
'0
LENGTH FREQUENCY Auxis thazard 40
35
30
25 ;>,
u s::: II) ;j
20
0" II)
•....
~
15
10
5
0 24
25
26
27
28
Fork Length (cm)
Figure 3:
Size composition of frigate tuna, Auxis thazard caught by K.K. Manchong purse-seine in April 1987 around a FAD very near to Terumbu Layanglayang.
LENGTH FREQUENCY TlIlIllIIIlS alhacares
20
18
16
14
12 >-,
u
c::
10
<1.l
::l
c:r
<1.l •... u.
8
6
4
2
0 22
26
30
34
38
42
46
50
54
58
62
Fork Length (cm)
Figure 4:
Size composition of yellowfin tuna, Thunnus albacares caught by trolling in waters off Terumbu Layang-layang during the April 1987 trip.
The carangids that are mostly caught by purseseine and here is mostly selar specifically Atule mate.
210d/48 150mm 2lOdn2 150mm
21Od/48 150mm
210d/48 150mm
2lOdn2 150mm
210d/48 114mm
21Od/60 114mm
21Od/33 76mm
21Od/48 76mm
21Od/33 50mm
210d/33 50mm
210d/33 38mm
210d/33 38mm Headrope length 471 m Groundrope length 55.5 m 4.0 m Net height (Theoritical) Twine size 210/33-210/48 Materials (Nylon polyamide) Estimates Resistance 4.0 tons
Appendix 2 Purse Seine Net for K.K. Manchon
in 1987
TOTAL FLOAT LINE LENGTH 449.1 M 39.8m
73.2m
287.1 m
49.1 m
384.1 m
64.0m
I
I
0.7
54.5m
96.0m
2
3
4
5
N2lOD 12 25m/m 600md 32.0 In
N2lOD 9 25m/m 600md 32.0m
N2lOD 9 25m/m 600md 37·0m
6
7
8
9
lO
II
N2lOD 12 25m/m 600md 32.0m
t::l
3 pes
v;
fj
25m/m' ~ 900md 3 900m1
14
15
16
17
18
19
ril N2lOD17 25m/m
N2lOD17 25m/m
N2lOD 7 25m/m 600md 32.0 m
N2lOD ~ 7" 25m/m i5 600md 32.0 m '"
f
N
4 pes
N
13
3 1 5Om/m 12MD
PE380D N
12
0.7
600mdlt64.Om
6OOmdlt64.Om
~ ...•
5 pes
5 pes
~ ,. ~ f
~
6 pes 6 pes
7 pes
7 pes 3/21 5Om/m 12MD
PE380D 23.7
46.2
61.2
76.2
91.2
91.2
11J6.2m
11J6.2m
76.2 ' NET DEPTH STR. m
I
20.3%
43.9m
18.1%
78.7m
17.6%
19.2%
316.4m
52.2m
I
3 I
,
48
76
82
96
96
82
74
62
62
62
62
62
76
90
102
114
102
90
76
,
3
,
