Shrimp Fisheries In Malaysia

Transcription

1 Shrimp Fisheries In Malaysia by Ahmad Ali Ibrahim Johari Marine Fishery Resources Development and Management Department, Southeast Asian Fisheries Development Center (SEAFDEC) Chendering, Terengganu, Malaysia. Paper presented in the Australian and FAO workshop on Selective Shrimp Trawling with selective device~darwin, AUSTRALIA July 1997

2 Shrimp Fisheries In Malaysia Ahmad Ali Ibrahim Johari Marine Fishery Resources Development and Management Department Southeast Asian Fisheries Development Center (SEAFDEC), Terengganu, MALAYSIA. The fisheries sector in Malaysia plays an important role in the national economy in term of income, gain of foreign exchange and employment to the rural population. Basically the fisheries industry in Malaysia can be divided into marine fisheries, aquaculture and public water bodies! inland fisheries. For management purpose, the marine fisheries is categorized into the inshore sector and the deep sea sector. The inshore fisheries is already heavily exploited and there is evidence that fishing is over saturated. In 1995, the total production from the fisheries sector amounted to 1,245,117 tonnes valued at RM 3.15 billion constituting about 1.47 % of the national Gross Domestic Product (GDP), while in 1994, the total production from the fisheries sector amounted to 1,181,763 tonnes valued at RM 2.99 billion and constituted about 1.61% of the national GDP. There was an increase of 5.36 % in terms of the quantity of the total production and 5.35 % in term of the value of the total production. However, there was a decrease in the contribution to the GDP by 8.70 %. (Annual Fisheries Statistic, 1994, 1995) With regard to employment, the fisheries sector in Malaysia provides direct employment to 82,000 fishermen and 18,466 aquaculturists giving a total of 100,666 man power employed in the fisheries industry in This constituted about 1.24% of tht labour force in the country. On the whole the fishing vessel in Malaysia increased from 31,403 units in 1994 to 34,906 units in The total number of gears licensed was 29,152 units. The major fishing gears were trawls net ( 19.32%), purse seine net ( 6.3 %), drift/gill nets (56.77 %) and hook and lines (8.47 %) (Annual Fisheries Statistic, 1995)

3 The total landing from marine capture fisheries increased by 4.02 % from 1,065,585 tonnes in 1994 to 1,108,436 tonnes in However the landing of Grade 1 fish and prawns decreased by 1.30% ( from 45,795 tonnes to 45,198 tonnes) and 8.12% ( from 101,748 tonnes to 93,488 tonnes ) respectively. Although there was a decrease in landing of Grade 1 fish, its value increased by 3.19% ( from RM million to RM million). The value of prawns being landed on the other hand decreased by 0.77% ( from RM million to million ). The other group of fish, i.e. Gred II and Gred III fish, trash fish, and shellfish showed an increased in landing in term of quantity. (Annual Fisheries Statistic, 1994, 1995) On the whole the shrimp landing in Malaysia decrease from 101, 748 tonnes in 1994 to 93,488 tonnes in The catches was landed from three areas namely Peninsular Malaysia, Sarawak and Sabahl Labuan. The bulk of shrimp was landed from the Peninsular Malaysia ( 70,062 tonnes), Sarawak ( 10, 198 tonnes) and Sabahl Labuan ( 13,228 tonnes) (Annual Fisheries Statistic, 1995). Various types of fishing gear are used to harvest shrimp in the country. The most dominant one is a trawl net, contribute more than 60 % of shrimp catches in Malaysia. The gear which has been operated since 1966 in the West Coast of Peninsular Malaysia, has been spread to all part of the country due to good catch. The trawl net of Malaysia could be grouping technically into two types, namely stern trawl and multiple rigs trawl. Stern trawl which locally call tiger net can be subdivided into three kinds; fish trawl, shrimp trawl and brine shrimp trawl ( Chokesanguan, 1989). The shrimp trawl and brine shrimp is made up of smaller mesh size at wing ( 4 cm or less) and is commonly being operated by smaller vessel of less than 25 GRT. However, there are some bigger vessels do operate dual type of gear, shrimp and fish trawl. The fish trawl is operating in the day and the shrimp one is at the night. The Fisheries Research Institute (1992) reported that the average catch of shrimp trawler in the West Coast of Peninsular Malaysia is around kg per boat per trip. The catches compose of two components namely commercial ( %) and trash (55-70 %). Trash fish is landed due to high demand from fish meal factory and cage marine cage culture operators. The multiple rigs trawl is popular in Sarawak. This gear can be sub-divided into two type, fish trawl and shrimp trawl. The shrimp trawl which made up of the smaller mesh size. at the wing panel ( < 4 cm) is only operated during the prawn season (November to Mac). Two or three nets are operated by a single vessel, therefore the bigger size vessel ( 25GRT) is used in the operation. The catch of the shrimp net generally compose of shrimp ( 70 %),

4 demersal fish (8 %), trash ( 20 %) and others ( 2 %). Trash is not landed and discarded at sea due to no market demand. In 1995, the shrimp trawl fishermen from West Coast of Peninsular Malaysia widely used the shrimp trawl that was modified to make the opening higher in order to catch fish from both pelagic and demersal species. Hence, the mesh size at the upper part is larger than at the lower part ( Hilmi A. H, 1996; Unpublished) Mesh size at the upper part of the net is about 10cm, while the lower part is 6.5 em. The material of twine is from PE (polyethelene) and twine size of each section are 380/12, 380/15,380/18 and 380/24. Length of head rope is about 12.5 m. Cutting rates of the main section of net webbing are 1N2B, 2N1B and 2N2B. Ground rope is made of PV A ( polyvinylamide) and the length is 13.0 m. Chain is SST 50 kg and spacers is Pb 12 kg. Bridles or sweepline is made of PV A ( kuralon) and the diameter is 20 mm and the length of bridle is about 20 m and is attached to warp or main rope by swivels. Trawl wire (warp) or hauling rope is made ofpv A ( kuralon) with diameter 25 mm and the length is 128 m. According to the Fishery Regulation 1995, all trawler must register under Zone B is allowed to operated beyond 5 nautical miles from the shoreline. Small boat ( under 25 GRT) always fishing for daily trip while the bigger boat fishing for more than one days. There or more hauls were conducted a day at towing speed about 3 knot for a duration of 3 hours. The fishing activities were carried out through-out the year. An average catch for daily trip during spring tide operation was kg/boat. The breakdown of the catch rate composition by group was shrimp 9.3 kg, pelagic fish 65.3 kg, demersal fish 34.6 kg cephalopod 22.7 kg, crab 4.7 kg and trash fish 330 kg. An average catch during neap tide was higher than spring tide. The catch is kg/boat/trip. Four main shrimp species caught during spring tide are P. merguinsis, M lysianassa, M dobsoni and M affinis. During neap tide species composition are same but the catches were higher than spring tide. The most dominant pelagic species during spring and neap tide is R. brachysoma. Scomberomorus commerson is the second major in the catches, followed by Sardinella fimbriata, Chirocentrus dorab, Scomberomorus spp, Atule mate and Stolephorus heterolubus. The most dominant demersal fishes during spring tide is Otolithes ruber, followed by Nibea soldadu, Anodontostoma chacunda, Atropus atropus and Nemipterus japonicus.

5 During neap tide, Pennahia macrophthalmus is the major in catches followed by Nemipterus hexodon, Cynoglossus lingua, Dasyatis spp and N. soldadu. Loligo duvauceli is dominant in catches and followed by Sepia aculeata during spring and neap tide. For crab, only Carybdis cruciata was caught during spring and neap tide. The catch usually clean but sometimes with some debris or sponges. The catches were group into demersal, pelagic, squid, crab and trash fish. All the commercial and trash catches are sold locally. Selectivity studies in Malaysia have been focused on trawl. Until 1997 there are several study in this field namely optimum mesh size of diamond mesh cod-end, by catch excluder device, two levels trawl, square mesh window and the latest is Turtle Excludel Device. Several trials on TED were conducted by MFRDMD and TD (SEAFDEC) researcher from 17 to 25 February This project aims to investigate the catch efficiency of shrimp trawlers using TED, the practical operation by local shrimp trawlers, and the efficiency of releasing turtles by shrimp nets fitted with TED. Preliminary result are quite interesting and encouraging, with the average escape rate less than 1% and 4% for shrimp and commercial fish, respectively. During the trials, a matured hawksbill turtle was captured inside the TED net cover, which provide evidence that this unit is able to release sea turtle through the exit hatch. The current research on BED is selectivity study of deep water trawl net. This three years research funded by Government on Malaysia. The problem of trash fish have been recognized for sometime, particularly in Peninsula Malaysia since the introduction of trawlers in the late 60's. Based on statistics' data, the landing of trash fish from trawlers have increased significantly in Malaysia. For example the landing of trash fish was increased 1.2 times higher in West Coast from 111,611 tonnes in 1980 to 135,43 tonnes in 1994 and 6 times higher in the east coast of Peninsula Malaysia from 17,748 tonnes in 1980 to 107,799 tonnes in Study on trash fish has been conducted to ascertain the composition of trash fish in trawl catches especially shrimp trawlers since the early 80's. Result from various studies showed that a singnificant amounted of trash fish was landed by those trawlers. Mohd Ibrahim (1987) has conducted a study at Sekinchan, Selangor in the west coast of Peninsula Malaysia and found that the shrimp trawler yields about 68.2% of trash fish in total catches. In the east coast of Peninsula Malaysia trawlers less than 25 GRT were fi:equently exploiting the prawn resources during monsoon season from Oktober to February. The catches of these trawlers consisted 64% of trash fish.

6 The demand for trash fish is still higher for brackish water cage culture and animals feed industries. To banned trawl net in Malaysia is almost impossible. The gear has significantly contributed to the bulk of prawn landing. The primary step should be taken is to strictly enforce the present regulation especially regarding the minimum mesh size of the cod end. At the same time studies to determine the suitable devices or technique in order to improve the selectivity performance of the gear should be proceeded. Chokesanguan, B Trawl. In Fishing gear and Methods In Southeast Asia II, Malaysia. Training Department, SEAFDEC, Bangkok: Mohd. Ibrahim M., Selectivity studies on Malaysian trawls. University Pertanian Malaysia. Ph. D. Thesis :219 pp.