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INDONESIA

REDUCING THE IMPACT OF TROPICAL SHRIMP TRAWLING FISHERIES ON LIVING MARINE RESOURCES THROUGH THE ADOPTION OF ENVIRONMENTALLY FRIENDLY TECHNIQUES AND PRACTICES IN THE ARAFURA SEA, INDONESIA


by the National Committee for Reducing the Impact of Tropical Shrimp Trawling Fisheries in the Arafura Sea; Directorate General of Fisheries Department of ocean Exploration and Fisheries, Jakarta; Jl. Harsono Rm No.3; Tromol Pos No.: 1794/JKS; Jakarta. 12550, Indonesia; Fax. 7803196; E-mail: statikan@rad.net.id )

Abstract

In 1996, the trawl fishery in Arafura Sea caught around 20 000 t of shrimp (80% Penaeids, y2859ely banana shrimp (P.indicus, P.merguiensis) 35% of the total, tiger shrimp (P. semisulcatus) and endeavour (Metapenaeus ensis)). In addition, there are important shrimp fisheries outside the Arafura Sea (with trammel nets, gillnets, and bottom seines).

The shrimp/bycatch ratio ranges from 1:8 to 1:15. The vessels retain and land more and more edible fish for the domestic markets but the discard rates of small fish (juveniles) are still high.

The shrimp trawlers are supposed to use a Turtle Excluder Device (TED) or a Bycatch Reduction Device (BRD).

In 1999, 453 vessels were involved (small wooden vessels fishing with one trawl, larger steel vessels using two trawls with outriggers).

Fishing with a trawl for shrimp is only allowed in the Arafura Sea and beyond the 10 m isobath (and with a licence to fish).

The y2859e problems reported include: weakness of monitoring and control of implementation of the regulations, lack of awareness of the existing fisheries regulations, increasing fishing effort and very high discard rates.

Resumen

En 1996, las capturas de camarón alcanzaron unas 20.000 toneladas métricas, producto de la pesquería de arrastre en el Mar de Arafura. El 80% de estas capturas fueron Penaeidos, principalmente camarón banana (P. indicus, P. merguiensis), mientras que el 35% del total estuvo constituido por camarón tigre ("tiger shrimp"; P. semisulcatus) y "endeavour" (Metapenaeus ensis). Adicionalmente, existen importantes pesquerías de camarón fuera del Mar Arafura en las cuales se emplean redes de trasmallo ("trammel nets"), redes agalleras/ de enmalle ("gillnets") y redes de fondo ("bottom seines").

La relación entre las capturas de camarón y la fauna de acompañamiento varía en un rango de 1:8 a 1:15. Las embarcaciones retienen y desembarcan cada vez más pescado comestible destinado el mercado doméstico, pero la tasa de descartes de pescado de tallas pequeñas (juveniles) continua siendo elevada.

Se supone que las embarcaciones de arrastre de camarón emplean dispositivos exclusores de tortugas (TED: Turtle Excluder Device) o dispositivos reductores de la fauna de acompañamiento (BRD: Bycatch Reduction Device).

En 1999, aparecen reseñadas 453 embarcaciones; básicamente, pequeñas embarcaciones de madera que pescan con una red de arrastre y grandes embarcaciones de acero, dedicadas al arrastre con tangones con dos redes.

La pesca de arrastre de camarón está permitida sólo en el Mar Arafura y más allá de la isóbata de 10 metros, siempre y cuando la embarcación posea licencia de pesca.

Los principales problemas reportados incluyen: debilidad en la vigilancia y el control de la implementación de las regulaciones, falta de conciencia en relación con las regulaciones pesqueras existentes, incremento del esfuerzo de pesca y tasas de descartes muy elevadas.

PREFACE

The Arafura Sea is one of the most important fishing areas for demersal fisheries, especially shrimp in Indonesia. Administratively, the waters are situated between the Province of Moluccas (Southeast Moluccas District) and Irian Jaya (District of Sorong, Fakfak, Manokwari and Marauke). The long distance from the local community area allows only industrial scale fisheries to exploit the fish resources.

Exploitation of demersal/shrimp resources in the Arafura Sea started in 1969. As the selectivity of the shrimp trawl is low, different fish species and fish of various sizes are caught.

Shrimp (Penaeid) is the target species of shrimp trawls operating in the Arafura Sea. Other fish and organisms are considered as by-catch and the discarded catches are substantial.

In view of promoting responsible fisheries, the issue of biodiversity is of great concern to the international community and the impact of its exploitation has been assessed. In cooperation with FAO, and other countries carrying out tropical shrimp fishing, a study on the reduction of the impact of tropical shrimp trawling on resources, using environmentally friendly fishing gear, will be carried out. Indonesia, one of the participating countries, has appointed a National Coordinator to prepare a National Report.

For the preparation of the national Report, based on the Decree of the Directorate general of Fisheries No. 13660/Kpts/Tu.110/110/XII/99, dated 22 November 1999, a committee was established to assist the National Coordinator.

The National report was presented at the Asian Regional Workshop, held in March 2000 in Denpasar, Bali. At the workshop, discussions were held on the efforts to reduce by-catch of shrimp trawling and management of shrimp and demersal resources in the Arafura Sea.

This activity is expected to draw greater attention to responsible fishing in order to ensure sustainable marine resources which, in turn, will lead to shrimp fishing in the Indonesian waters being sustained.

Sugiri Elon
National Coordinator


1. INTRODUCTION

Fishing for shrimp using trawls in the Arafura Sea has been ongoing since 1969. Through cooperation on exploratory fishing between the Marine Fisheries Research Institute (Lembaga, Penelitian Perikanan Laut), Jakarta and a Japanese fishing company, the growth of fishery has been steadily increasing over the years, in actual fact from 9 to 453 units in 1999.

The shrimp trawl is the most productive fishing gear in the exploitation of demersal fish resources including shrimp. The target species is shrimp (penaeids), whereas other catches are considered as a by-catch product.

Under the Code of Conduct for Responsible Fisheries implementation, some countries and international organizations agree that in terms of utilisation of the marine resources, the development and use of selective fishing gear should be a priority.

In Indonesia trawling for shrimp is restricted: Presidential Decree No. 39 of 1980 bans trawls, however, Presidential Decree No. 85 of 1982 allows shrimp trawl operations from the shore, 130oE of East Indonesia if using Turtle Exclusion Device (TED) or Bycatch Excluder Device (BED).

Within the Project Development and Preparation Phase (PDF), GEF/FAO, a number of countries with by-catch problems have agreed to pay attention to reducing the impact of fishing on marine resources, the following being their y2859e goals:

1) identification of fisheries where the by-catch or discard problem or habitat impacts are particularly severe.
2) identification of any barriers (technical, economical, human, etc.) which make change difficult.
3) identification of the potential roles of different stakeholders at the national level.
4) preparation of a y2859e phase project.

In March 2000 a regional workshop was held in Denpasar, Bali. The following topics were considered:

1) collection of data and information network system.
2) setting up of close cooperation with fishing industries.
3) agreements on cooperation: proposals and conditions of execution.
4) setting up of a Nucleus Estate Smallholder (NES) scheme with shrimp trawl industries.

It was agreed that the y2859e project would cover several activities such as:

1) testing and demonstrating By-catch Reduction Devices (BRDs) application in some fishing areas.
2) analysing (in detail) the impact of the shrimp trawl fisheries.
3) defining management measures (taking into account the development of efficient by-catch reduction devices and an assessment of the situation of living resources and their environmental factors).

2. THE STATUS OF SHRIMP FISHERIES IN THE ARAFURA SEA

2.1 Fishing Areas and Conditions

2.1.1 Fishing Areas

Commercial trawling in the Arafura Sea began under a joint venture between Indonesia and Japan. Today companies under Domestic Capital Investment (PMDN) are also involved. Approximately 72 000 km2 (Naamin 1984) of shrimp trawl areas have been intensively exploited.

1) Kepala Burung area (sub-areas I and II) covering Sele Straits, Bintuni Bay, Fakfak, Adi Island and Kaimana waters.
2) Dolak and adjacent areas (sub-area IV) which covers Kokonao waters, Aika, Mimika, Uta river mouth, Aidma and Digul.
3) Aru and adjacent areas (sub-area III) which covers eastern, southern and western parts of the Aru Islands (see Figure 1).

Figure 1. Distribution of fishing ground of shrimp trawler in Arafura Sea of Indonesia

2.1.2 Fishing Area Conditions

1) Kepala Burung cover approximately 15 000 km2. Sea conditions are relatively calm and there are many small and large river mouths. The seabed is sandy and muddy and the colour of the water is almost grey. Dense mangrove growth is found along the coasts of Sele, Bintuni Bay and Kaimana.

2) Compared to other areas, Dolak is relatively wide, approximately 45 000 km2 with dense mangroves along the coast and many river outlets. The condition of the seabed is generally muddy, sometimes muddy and sandy, and crabs and crustaceans are frequently found. The colour of the water is brown due to the strong river current. Shrimp is caught at a depth of between 5-50 m.

3) The total fishing ground of the Aru and adjacent areas is approximately 13 000 km2 . The seabed is slightly harder, consisting of a mixture of mud and sand, sometimes sand alone, and in certain areas crabs and crustaceans are found. In general, there are a lot of mangroves along the coast. Shrimp is y2859ely caught at a depth between 4-40 m.

2.2 Fishing Activity

2.2.1 Gear Used

Since 1969, when the shrimp fishery started commercially, the trawl has been the y2859e gear used. There are three types of trawl used in the Arafura Sea, namely:

1) Double rig shrimp trawl: the headrope length is between 15 and 26 m. The mesh size of the codend is generally 11/14 inches (30 mm) and made of polyethylene (3 80D/72). A trynet, with a headrope length between 2 and 4 m is used.

2) Single rig stern trawl: headrope length between 26 and 35 m.

3) "Quad trawl": this type has 4 codends. The headrope length is between 20 and 25 m.

According to Presidential Decree (Keppres) No. 085/1982 each unit should be equipped with a BED (By-catch Exclusion Device) which is a modified form of TED (Turtle Excluder Device).

2.2.2 Fleet Structures

Presently, there are 453 units trawling for shrimp in the Arafura Sea. The size varies from 19 to 849 GT.

TABLE 1. Number of trawlers by size in GT

Size class (GT)

Units

10-20

20-30

30-50

50-100

100-200

>200

1

7

37

191

171

46

TOTAL

453

It should be pointed out that the predominant size of the trawler is 10-100 GT, followed by 100-200 GT. The smaller vessels (<100 GT) are mostly wooden vessels. The overall length varies from 20 to 45 m (see Table 2).

TABLE 2. Number of Trawlers, by size, in length

Metres

Units

20-25

25-30

30-35

35-40

40-45

167

168

63

30

25

TOTAL

453

The trawler's age varies from 7 to 40 years.

2.2.3 Shrimp Fishing Companies

The shrimp fishing companies operating in the Arafura Sea can be categorised into four groups:

1) Joint venture (overseas, PMA and PMDN).
2) National company, non PMA/PMDN.
3) Cooperatives.
4) State company (BUMN).

TABLE 3. Number of Trawlers by company group

Company Group

Units

Joint Venture

National company

State company

Cooperatives

86

361

1

5

TOTAL

453

2.2.4 Fishing Operations

In general, the duration of fishing trips vary from 40 to 60 days and the average total days at sea are approximately 280 days per year. There are approximately 7-9 hauls a day.

2.3 Fishing Effort

In 1999, there were 453 shrimp trawlers in operation. In general, the 50 GT trawlers, or smaller, are stern trawlers, whilst the larger ones are outrigger trawlers. Haul duration is between 2 and 3 hours, with towing speeds varying from 2 to 3 knots.

Catch data (1990-1998) collected by HPPI (Association of Shrimp Trawl Companies), gives the catch per unit of effort (kg/hauling), average number of hauls per day and average operational days per vessel as presented in Table 4.

The total catch and effort is calculated based on the Arafura trawlers catch data, which is recorded by HPPI.

The change in fishing effort from 1990 to 1998 is given in Table 4. Overall calculations of fishing effort in the Arafura sea in 1999 were estimated to be 86,640 operational days or 632,472 hauls. It can be seen that even though the amount of effort has increased, the catch per unit of effort (kg/haul) rey2859es stable.

TABLE 4. Calculation of fishing effort of shrimp trawlers in the Arafura Sea

Z

Year

Vessel (unit)

 

Days at sea

Number of hauling

Catch

Average Total

Per day

Total CPUE (kg/Hauling) Total (Tones)

1

2

3

4

5

6

7

8

9

1990

1991

1992

1993

1994

1995

1996

1997

1998

285

390

439

359

343

374

431

431

453

304

302

266

264

279

275

274

271

257

86,640

117,780

116,774

94,776

95,697

102,850

118,094

116,801

116,421

7,3

7,5

8

8,2

8,9

7,6

8,2

8,2

8,4

632,472

883,350

934,192

777,163

851,170

781,660

968,371

957,768

977,936

33

37

31

25

28

34

31

34

30

20,872

32,684

28,960

19,429

23,848

26,576

30,015

32,564

29,338

2.4 Catches

2.4.1 Catch Composition

Catch composition consists of Penaeids species as the target species and demersal fish as well as other (non fish and non shrimp) as a by-catch. The y2859e species caught are given in Table 5.

TABLE 5. The main species caught by shrimp trawlers in the Arafura Sea

Family

Species

Indonesia name

English name

Demersal fish

Leiognathidae

 

 

Sciaenidae

 

Ariidac

 

 

Dasyatididae

 

 

 

Gerreidae

Lutjanidae

 

 

 

 

 

Mullidae

 

L. bindus

L. equulus

Gazza minuta

Johnius sp

Ototithes ruber

Arius thalasinus

Arius maculatus

Arius cealatus

Dasyatis kuhlii

Himantura uarnak

Hypolophus sephen

Rhinoptera javanica

Gerres abbreviatus

Gerres acianes

Gerres filamentosus

Lutjanus bohar

Lutjanus erythropterus

Lutjanus Johni

Lutjanus malabaricus

Upenerus sulphunerus

U. bensasi

 

Petek, peperck

 

 

Tigawaja, gulamah

 

Manyung

 

 

Pari

 

 

 

Kapas-kapas

 

 

Barnbangan, kakap

 

 

 

Kuniran, biji nangka

 

Pony fishes

 

 

Croakers, jewfishes

 

Cat fishes

 

 

Stingrays

 

 

 

Silver biddies

 

 

Snappers

 

 

 

Goat fishes

 

Nemipteridae

 

 

Polynemidae

 

Pomadasydae

 

 

Synodontidae

 

 

Teraponidae

U- tragula

Nemipterus hexodon

Nemipterus japonicus

Nemipterus peroni

Polynemus plebeius

P. sextarius

Pomadasys kaakan

P. maculatus

P. multimaculatus

Saurida tumbil

S. undosquamus

S. micropterus

Terapon threraps

 

Kurisi

 

 

Kuro

 

Gerot-gerot

 

 

Beloso

 

 

Kerong-kerong

 

Threadfin breams

 

 

Threadfin

 

Grunt sweetlips

 

 

Lizard fishes

 

 

Grunters

 

Trichiuridae

 

Penacidae

Terapon jarboa.

Trichiurus savala

T. lepturus

Penaeus monodon

P. semisulcatus

P. merguiensis

P. latisulkatus

Metapenaeus spp.

Parapenaeopsis spp.

 

Layur

 

Udang windu

Tiger

Udang putih

Udang raja

Udang dogol

Udang krosok

 

Hairtails

 

Black tiger

Flower tiger

Banana

King shrimp

Endeavour

Rainbow shrimp

TABLE 6. Catch composition and catch rate of double rig shrimp trawler Bawal Putih II in the Arafura Sea

No.

Area

1990

1991

1995

1996

1997

1998

1

Bintuni

           
 

- Fish (%)

74.4

79.0

       
 

- Shrimp (%)

23.6

200

       
 

- Other (%)

2.0

1.0

       
 

- C/Ft (kg/haul)

85

214

       

2

Dolak

           
 

- Fish (%)

84.0

85.0

94.5

86.0

94-3

86.2

 

- Shrimp (%)

12,5

7.4

4.6

11.5

3.8

11.1

 

- Other (%)

3.5

7.6

0.9

2.5

1.9

2.7

 

- C/Ft (kg/haul)

237

246

547

300

990

359

3

Kaimana

           
 

- Fish (%)

 

76.8

 

85.7

85.7

82.9

 

- Shrimp (%)

 

16.1

 

11.4

11.4

11.8

 

- Other (%)

 

7.1

 

2.9

2.9

5.3

 

- C/Ft (kg/haul)

 

246

 

2.5

2.5

229

4

Aru Island

           
 

- Fish (%)

84.1

89.6

81.3

85.0

85.0

83.2

 

- Shrimp (%)

8.9

9.0

14.3

9.0

9.0

8.0

 

- Other (%)

7.0

1.4

4.4

6.0

6.0

8.8

 

- C/Ft (kg/haul)

223

406

260

389

389

298

5

Arafura Sea

           
 

- Fish (%)

84.0

85

87

89

89

84

 

- Shrimp (%)

12.0

9

10

7

7

11

 

- Other (%)

4.0

6

3

4

4

5

 

- C/Ft (kg/haul)

276

510

258

408

408

341

 

- C/Fu Shrimp

33

45

34

30

30

37


TABLE 7. Composition of demersal fish caught in the Arafura Sea by shrimp area, in 1990-1991

No.

Species

Bintuni

Kaimana

Dolak

Aru

Sum

I

DemersaI fish (kg)

 

28,310

249,889

73,948

353,955

 

1 . Leiosnathidae

1,808

5,479

12,299

10,895

28,864

 

2. Mullidae

191

912

4,139

7,935

12,991

 

3. Nernipteridae

­

393

7,311

4,421

12,1125

 

4. Pomadasydae

9

1,874

8,666

4,229

14,779

 

5. Threponidae

28

553

4,685

6,431

11,697

 

6. Sciaenidae

1,206

9,659

96,473

8,473

107,338

 

7. Synodontidae

189

716

21,596

2,226

24,727

 

8. Lutjanidae

23

101

737

744

1,605

 

9. Harponidae

­

­

10,129

473

10,602

II

Pelagic fish (kg)

1,387

12,614

94,674

32J67

140,842

 

Number of hauling

32

205

884

340

1,461


Other groups of species such as bivalve, sea snake and other live organisms were rarely caught. Based on 450 hauls made by RV. Bawal Putih II, only seven turtles were accidentally caught.

The catch data of a 380 GT double rig shrimp trawler in the Arafura Sea, during 1990-1998, pointed out that the catch composition consisted of approximately fish 83-89%, shrimp 7-13%, and other organisms 3-6%.

In the Bintuni waters, the recorded fish catch was 74-79%, shrimp 20-24%, and other organisms 1-2%. In 1996 the fish and shrimp ratio was 95:4.

Catch composition of fish in the Dolak waters was between 84-95%, shrimp 4-13%, and other organisms 2-8%. This varies each year.

In Kaimana the recorded ratio was 77-86% of fish, 11-16% of shrimp, and 2-7% of other organisms.

While in the Aru and adjacent waters, the composition of the catch was 81-90% fish, 8-14% shrimp, and 1-9% other organisms.

2.4.2 Fish Composition

From 1,461 hauls, catch production of fish during 1990-1991 was on average: 242kg/haul, which consisted of 30% croackers and jew fish, 8% pony fish and 7% lizard fish. The composition of fish caught varies according to the fishing areas, as shown in Table 7.

In Bintuni Bay, from 32 hauls the average fish caught was 57 kg/haul; dominated by pony fish, croackers, jew fish and lizard fish.

In the Kaimana waters, from 205 hauls the average fish caught was 138kg/haul; dominated by 34% croackers, jew fish and 19% pony fish.

In the Dolak waters, from 884 hauls the average fish caught was 283 kg/haul; dominated by 39% croakers and jew fish, 5% pony fish and 9% lizard fish.

In the Aru Island waters, from 340 hauls the average fish caught was 217 kg/haul; dominated by 15% pony fish, 11% croackers, jew fish, goat fish and grunters, and 6% threadfin breams.

2.4.3 Shrimp Composition

Shrimp composition which has already been presented in Table 5, can be categorised into 5 groups as follows: tiger, banana, endeavour, rainbow and other shrimp.

The shrimp composition consisted of 19-35% tiger shrimp Penaeus semisulcatus, 29-43% banana shrimp Penaeus indicus; Penacus merguiensis, and 21-31% of endeavour shrimp. The catch compositions vary every year, depending on the fishing area (see Table 8).

In Bintuni Bay it was on average 30-37 kg/haul, consisting of 8% tiger, 56-69% banana and 17-20% endeavour.

In Kaimana the catch is on average 23-38 kg/haul, consisting of 16% tiger, 44% banana and 27% endeavour.

In Dolak the catch is on average 20-34 kg/haul, consisting of 15% black tiger, 51% banana, and 23% endeavour.

In Aru Islands waters the catch is on average 20-25 kg/haul, consisting of 52% black tiger, 4% banana, and 22% endeavour.

TABLE 8. Shrimp caught by shrimp trawl of PT. Bina Utama by fishing ground during 1992-1996

 

 

Arafura Sea

FishingGround

No

Year

Total

Bintuni

Keimana

Dolak

Aru

1.

Shrimp Catch (Kg)

 

 

 

 

 

 

1992

º

141,243,0

29,948.0

47,898.0

432.0

 

1993

297,926.0

57,483,0

14,802.0

143,276.0

79,406.0

 

1994

106,879.0

16,845.0

14,703.0

48,152.0

81,788.0

 

1995

340,115.0

106,488.0

27,040.0

140,007.0

26,358.0

 

1996

208,262.0

38,614.0

-

59,756,0

109,818.0

2.

CPUE (Kg/Hauling)

 

 

 

 

 

 

1992

26.4

36.3

27.3

20.1

20.2

 

1993

27.9

29.6

23.2

34.4

25.4

 

1994

30.4

36.7

37.7

31.7

22.9

 

1995

29.3

34.8

37.4

33.9

25.4

 

1996

22.5

35.2

26.8

27.5

19.6

2.4.4 Other Organisms Caught

Other organisms such as squid, lobster, bivalve, turtle, sea snake and crab were caught in different quantities according to the fishing ground.

From May to October 1991 the RV Bawal Putih II in Dolak, caught 3,637 kg (or 6.7 kg/hour) in 546 hauls. An average of only 1.9 kg/hour was caught in shallow waters, whilst beyond a 20m depth the average was 4.9 kg/hour.

215 successful hauls resulted in an average of 1,932 kg or 9kg/hour in the Aru Sea. In deeper waters (more than 20-40 meters in depth) it was 9.2 kg/hour, while in shallower waters, only 7.1. kg/hour.

In Kaimana and Minika waters, 277 successful hauls gave 937 kg or, on average, 3.4 kg/hour. Beyond a depth of 40m, catch per hour was 2.3 kg.

2.4.5 Production Trends of Sea Fisheries Resources

From 1990-1997, the fish production in the Arafura Sea, which includes Moluccas Province (Southeast Moluccas district) and Irian Jaya Province (Sorong, Fakfak, and Merauke districts) increased yearly from 66,324 tonnes to 199,314 tonnes, or, an average of 33% per year.

Production of demersal fish increased every year, from 14,525 tonnes to 86,326 tonnes, an average increase of 82% per year. The important commercial demersal fisheries resources were: snapper, pompfret, cat fish, and thread fin fish.

The ever increasing rate of pelagic fish was 24% per year, or, from 24,490 tonnes in 1990 to 59,934 tonnes in 1997. The important commercial pelagic fisheries resources were tuna, tongkol, skipjack, shark and others.

The crustacean production increased by approximately 10% per year, from, 11,018 tonnes in 1990 to 17,864 tonnes in 1997. The crustacean composition was dominated by penaeids shrimp of black tiger, banana, endeavour, and rainbow shrimp Parapenaeopsis spp.

Other crustacean compositions were swimming crab, mudcrab, and lobster in relatively small quantities.

Apart from the resources mentioned above, bivalve, squid, turtle, jelly-fish and sea cucumber were landed. Production increased yearly, from 904 tonnes in 1990 to 5,639 tonnes in 1997.

2.4.6 Landing of By-catch Fish

It has already been noted that the shrimp trawl catches consist of shrimp, fish and other organisms. Any species other than the target species (shrimp) are considered as by-catch, of which some of them are landed and the rest discarded.

Table 9 shows that, in comparison to shrimp, a relatively large quantity of fish and other organisms are caught by shrimp trawls. According to estimates, it varies from 20 to 39 kg/haul or 160 to 312 kg/day.

TABLE 9. Estimate of by-catch landed by shrimp trawlers

Year

Average landed
(kg/hauling)

Number of hauling
(times)

Landing
(Ton)

1990

20

632,472

12,649

1991

22

883,350

19,434

1992

20

934,192

18,684

1993

22

777,163

17,098

1994

22

851,170

18,726

1995

35

781,660

27,358

1996

39

957,768

37,766

1997

34

977,936

32,564

1998

25

574,773

24,448

The composition of the by-catch of shrimp trawls landed in Ambon and Sorong is shown in Appendix 1.

2.4.7 Standing Stock and Potential Yield

The estimated swept area is:

A = 2/3 HR (Head rope length) x Vessel's speed in knot x 1852 (1 knot = 1852 m/hour) x 2 (2 trawls towed at the same time with the outrigger rigging)

The catchability factor is estimated at 0.5 (Shindo,1973), i.e. that only 50% of fish and shrimp available were actually caught. Therefore, the stock density (ton/km2) is equal to:

Catch average (kg/hauling)
A x 0.5

Calculation is based on catch of KM, Kurnia VII a double rig shrimp trawler of 180 GT.

In table 10, the overall standing stock for the Arafura Sea was estimated by multiplying the stock density by an area where it was possible to trawl.

The potential yield (Py) is estimated by using the formula Py = X (Y+MBo) (Gulland, 1968) where X is a constant (0.5), Y is the shrimp production of the Arafura Sea (16,973 tonnes in 1997), M is the natural mortality (0.5) and Bo is shrimp biomass (tonnes). The results give an estimate of a total potential yield (Py) for penaeid shrimp in the Arafura Sea of 20,501 tonnes for a fishing effort of 89,663 days which is equal to 320 vessel units (for an average of 280 operational days per year).

TABLE 10. Calculation of standing stock of shrimp resources in the Arafura sea

No

Fishing areas

Tiger

Banana

Endeavor

Other Shrimp

Total

1 Bintuni & Kaimana          
  C (kg/hauling)

5

13

6

5.5

29.5

  p i (kg / km2)

98

256

118

108

580

  Bo (ton)

1,470

3,840

1,770

1,620

8,700

2 Dolak          
  C (kg/hauling)

2

18

11

6

37

  p i (kg/km2)

39

354

216

118

727

  Bo (ton)

1,755

15,930

9,720

5,130

32,715

3 Aru          
  C (kg/hauling)

9

1

6

10

26

  p i (kg / km2)

177

20

9,118

197

511

  Bo (ton)

2,301

260

1,534

2,561

6,643

  Arafura sea

5,526

20.,030

13,024

9,491

48,058

Remarks:

C is an average of shrimp catching production (kg/haul).
Pi is the shrimp stock density (kg/km2).
Bo is shrimp biomass (tonnes).
The total potential yield (Py), 20,501 tonnes consists per fishing area in:

Considering the shrimp production estimate in 1998, 29,338 tonnes, as presented in Table 4, it would seem that the shrimp exploitation rate in the Arafura sea has already reached its maximum.

Data analysis of catch and effort from 1969 to 1981 for overall important commercial penaeid shrimp species in the Arafura Sea, by using Schaeffer and Fox models, gave a MSY value range from 14,700 to 15,000 tonnes per year. The optimal effort is 39,000 days which is the equivalent of 138 trawler units with a 500 HP, or, 215 actual days in operation per vessel/year.

The MSY estimated value for Penaeus merguiensis (banana shrimp) which is the y2859e species caught, is between 6,400-6,550 tonnes per year with optimal catch effort ranging from 22,300 to 27,700 days of standard vessel (Naamin, 1987).

Other estimates of potential yield (1969-1990 data) when using the same models show that the MSY value was 10,350 tonnes per year; optimal catch per unit of effort was 33,676 vessel days. It would seem that the exploitation rate was again, nearly, completely exploited (DGF, 1995).

By using different data catch, i.e. 1982-1987 (Naamin, 1992) or 1985-1990 (Iskandar et al, 1993), the estimated value of MSY was 13,800 tonnes or 8600 tonnes respectively. The final result revealed that the exploitation rate for each period had nearly reached the fully exploitable level.

3. SHRIMP TRAWLING MANAGEMENT ASPECT

3.1 Fisheries Resources Management Policy

The fisheries resources management was established under Law No. 9 of 1985 on Fisheries. It states that fisheries resources management refers to all the measures taken to sustain and utilise the fisheries resources in an optimal manner. It includes measures for controlling fishing efforts to a level sustainable for fisheries resources, fishing practices acceptable for environments and assessment of other activities which impact fisheries resources and its environments.

Furthermore, Law No. 9 of 1985, para 4. includes management principles to be implemented under the Ministry of Agriculture; responsibilities which concern the following:

(1) regulation of the size of fishing gear.
(2) regulation of characteristics for fishing vessels and technical requirements for navigation
safety.
(3) estimation of Total Allowable Catch (TAC) per species.
(4) establishment of Fishing Zonation (to protect small-scale fisheries) and fishing
season/closed season.
(5) protect fisheries resources and environment from pollution and other damage; conduct
rehabilitation and conservation of fish and its environment.
(6) introduction of species (to enrich fisheries potential).
(7) other related issues needed for fisheries management (for example controlling fisheries
resources, participation of community, etc.).

The regulation of fisheries resources management consists into 8 categories of measures as follows: 1) regulation for mesh size; 2) regulation for TAC and minimal size of fish to be caught; 3) closed and open fishing season: 4) closed and open fishing in certain areas; 5) regulation for fishing gear and other related gear (for example: Fish Aggregating Device/"rumpon" type; 6) rehabilitation and conservation of fisheries resource; 7) regulation for issues related to species, conservation and fishing area approach; 8) regulation for relevant technology in terms of conservation of all species in a certain area or in general.

Each of the above regulations will be used for fisheries resources management in the Arafura Sea, especially in terms of controlled operations of shirmp trawls.

3.2 Implementation of Shrimp Trawl Management

3.2.1 Trawl Banned and Shrimp Trawl Operation

Before Law No. 9 of 1985 on Fisheries, Government Regulation (PP) No. 15 of 1990 on Fisheries Business and Ministry of Agriculture Decree No. 815 of 1990 on The Authority of Fisheries Business License in the certain scale is a responsibility of the Local Government (Provincial Fisheries Service), that refers to Government Regulation No. 64 of 1957. Licences for fishing vessels used by foreign companies are issued by the Directorate General of Fisheries.

If capital investment is available, the licence is authorised by the Capital Investment Coordinating Agency/BKPM.

Regarding trawling by national companieslicences are issued by the local government, within the limits established by the regulations in Indonesia.. For the Arafura sea, licences for trawling are issued by both the Directorate General of Fisheries and CICA/BKPM (for fisheries businesses that have a facility of capital investment of Foreign Capital Investment/PMA and Domestic Capital Investment/PMDN).

With regard to the development of fisheries, the use of trawlers is controlled in order to y2859etain the fisheries resources sustainability and to prevent social conflicts among fisheries, y2859ely in the coastal areas where there is heavy fishing pressure by fishing vessels of different sizes. In light of this, fishing zonation for fishing vessels has been established to avoid resources being damaged and conflicts arising among the fishermen. Ministry of Agriculture Decree No. 607, of 1976, regulates the zonation. To protect small-scale fisheries from large-scale operations in their fishing grounds, the fishing grounds are divided into several zones to be utilised respectively by certain sizes of fishing vessels. Based on the decree, four areas/fishing zones are identified, as follows:

a) Fishing Zone I excluding:


b) Fishing Zone II excluding:

c) Fishing Zone III excluding:

d) Fishing Zone IV.

Trawl is the most effective fishing gear used to catch demersal fish, but also the cause of conflict of interests with the small-scale fisheries sector which has simple fishing gear, most of them set, passive, gear which are caught in the trawls.

The zone problem, especially in the Arafura Sea is not regulated by Ministry of Agriculture Decree No. 607 of 1976, however, there is another regulation which requires shrimp fishing to be undertaken beyond the isobath line 10 meters (Presidential Decree No. 85 of 1982 refers). This regulation in the Arafura Sea, does not limit the development of uncontrolled trawling. Therefore, under Presidential Decree No. 39 of 1980, the government decided a ban on trawling, the implementation of which is being done step by step.

The Ministry of Agriculture Decree No. 503/Kpts/Um of 1980 on Steps for Implementation of Banned Trawls Phase I includes a description of the trawl models which are banned. A Joint Cooperation Decrees (SKB) issued by three ministries, Home Affairs, Trade and Cooperation and Agriculture (No. 596/Kpts/Um/8 of 1980, No. 183 of 1980, No. 345/Kpb/VIII of 1980) includes guidelines for the Transfer of Fishing Vessel Free Trawl. Other Decrees of the Ministry of Agriculture regulate fishing activities such as Ministerial Decree No. 694/Kpts/Um/9 of 1980 which concerns b"Boundaries of Fishing Ground Area for Fisheries Business using Trawl" and Ministry of Agriculture Decree No. 542/Kpts/Um/6 of 1981 limiting the number of trawlers in the Province outside Java, Bali and Sumatera respectively.

The last phase was to ban trawling in all Indonesian waters through Presidential Introduction No. 11 of 1982 on Implementation of Presidential Decree No. 39 of 1980 which states that the rey2859eing trawls used from 1 January 1983 are now banned totally in all Indonesian waters.

However, since the total trawl ban was issued, the government still allows specific types of trawls such as shrimp trawl. Considering that - shrimp production is needed to generate foreign currency, - the technology exists to reduce by-catch from trawl, - there are still fishing grounds which has not been exploitedand - capital investment policy (both Foreign Capital Investment/PMA and Domestic Capital Investment/PMDN), shrimp trawling is still authorized in areas such as: Arafura waters, Kei, Tanimbar and Aru, beyond 130oBT East.

Regarding its implementation, the regulations concerning fishing zones and trawl specifications are subject to violation. Gillnets or surrounding nets are modified or fishing operations are adjusted to take advantage of existing trawl regulation. The utilisation of certain gear in coastal areas creates severe conflicts between fishermen.

Indeed, monitoring at sea is conducted by both Fisheries Officers and Law Officers (Indonesian navy/TNI AL and Marine Police). However, because of the lack of means, financial and human resources, violations are frequent.

3.2.2 Controlling of Shrimp Trawl Net

As previously mentioned, the fisheries resources management has regulations. The implementation is, generally, as follows:

(1) Fisheries Resources Allocation

"Fisheries Resources Allocation" basically concerns the fishing effort being authorized in given areas, including for shrimp trawling. It is issued by means of Ministry of Agriculture Decree No. 995/Kpts/IK.120/9 of 1999. This Decree estimates the TAC for shrimp to 17,200 tonnes (while for demersal fishes, a total of 197,400 tonnes). Therefore, if the average CPUE for shrimp trawl net is around 10 ton/year (with fishing vessels 150-200 GT) then the number of shrimp trawl net to be operated in the Arafura Sea would be 156. Considering that the number of shrimp trawl net operated in the Arafura Sea is now 453 for a production amounting to approximately 49,830 tonnes, the conclusion is that shrimp is being over-fished in the Arafura Sea.

(2) Mesh Size Regulation

The regulation concerning mesh size is found in the Ministry of Agriculture Decree No. 392/Kpts/IK.120/4 of 1999: the minimal mesh size requirement is usually 25 mm (1 inch). This also applies to shrimp trawl net.

(3) By-catch Excluder Device (BED)

A pre-requisite of shrimp trawl net operation is the use of fish selective gear. The goal is to select fish in certain sizes. A BED can be installed between the body and the codend (Certains dimensions of the BED are adjusted to match the size of the trawl net). Shrimp fishing companies have the obligation to use BED in the Arafura Sea.

However, fishing companies report that BED is cumbersome and that it reduces the effectiveness of the trawl operation. Therefore, more research is required.

(4) Regulation for Fishing Zones

The regulations concerning the Fishing Zones aims to: 1) conservation of fisheries resources, especially in coastal areas, protection of nursery grounds, 2) protection of small-scale fisheries from competition with larger scale fisheries, 3) avoid conflicts among fishermen, in general.

The regulations concerning fishing zones is now found in the Ministry of Agriculture Decree No. 607/Kpts/Um/9 of 1976but it does not concern shrimp trawling operations since it does not apply to the Arafura Sea. In East Indonesia, only shrimp trawling is regulated with a use limited to beyond the 10 meters isobath line (Presidential Decree No. 85 of 1982).

The 10 meters isobath line limit is often not applied and shrimp trawlers often operate inshore where the depth is less than 10 meters in depth, even in estuaries. In these conditions, nursery grounds for shrimp/fish are affected and the sustainability of the resources is threatened.

(5) Pre-requisites for Fishing Vessels

The Ministry of Agriculture Decree No. 392 of 1999 regarding Fishing Zones authorizes Indonesian and Foreign Fishing Vessels to operate in the IEEZ area (except in Malaca Strait) using (whatever fishing gear is used) vessels not more than 350 GT. In accordance with the above, shrimp trawl net is authorized in the Arafura Sea only with trawlers less than 350 GT.

(6) Utilisation of Fish By-Catch

The fishery companies that have licenses to use shrimp trawl net have to hand over "fish by-catch" to the Fisheries/Cooperatives State owned Company/BUMN. Regulation on utilisation of fish by-catch is includedin the Presidential Decree No. 85 of 1982 and Ministry of Agriculture Decree No. 930/Kpts/UM/12 of 1982 and the Directorate General Fisheries Decree No. IK 010/S3.8063/82K, While the optimal fish by-catch utilisation is in line with responsible fisheries principles, the above mentioned requirement of keeping the by-catch on board is, practically, not easy to implement because of room limitation in the fish hold and time and effort which would have to be dedicate to handling this portion of the catch.

(7) Coordination of Fishing Management

Regarding proper preservation of resources and environment, sustainability of fisheries, with, if possible, some development the government has taken measures concerning fishing control and monitoring in Indonesia. The basis of this system is the delegation of authority given in this respect to regional governments, especially regarding fishing activities carried out by small fishing units, less than 30 GT and 90 HP.

The application for this management system is conducted through a Fisheries Resources Utilisation Coordination Forum (Forum Koordinasi Pengendalian dan Pemanfaatan Sumberdaya Ikan/FKPPS) which have annual meetings. The status of FKPPS is described in Ministry of Agriculture Decree No. 994/Kpts/Kp.150/9 dated 1999. Nine FKPPS have been established for the various areas of the countries. The Arafura Sea is included in FKPPS area VI.

The coordination forum discussed interests and related matters such as fishery regulation, in general, resources allocation, fisheries operation, both industrial and small-scale, fisheries monitoring and control, etc.

The above matters apply in particular to the Arafura Sea. However, it is worth reminding that regarding shrimp trawling, most of the relevant regulation is already under Presidential Decree No. 85 of 1982, including the limitation of the number of shrimp trawlers being authorized in the area (based on the issue of Fishing Permit (UP) for operation in the Arafura Sea).

4. RESEARCH ACTIVITIES

4.1 Results Obtained

As already mentioned, commercial shrimp fisheries in the Arafura waters, and its surrounding areas, began in mid 1969. The activities started with the operation of nine units of 100-300 GT. Since, the number of vessels increased rapidly, the equipment on board was modernized and the techniques improved.

Two periods can be distinguished for shrimp fishing development in the Arafura sea: before the introduction of By-catch Reduction Device (BRD) and after, from 1982.

The relevant research activities include those concerning shrimp resources (distribution, biology and population dynamic) and environment, fishing gears, socio-economic and by-catch utilisation.

4.1.1 Research on living resources

The research activities in the field consist in species identification, species composition, stock assessment, shrimp resource distribution (fishing grounds and seasons), shrimp population parameters and biology. Both, research vessels and commercial fishing units are used.

Information collected in Arafura waters, amongst others, includes:

(1) shrimp species caught, in general
(2) species and size composition of shrimp caught according to the fishing ground
(3) distribution of effort and catch per species according to water depth and condition of seabed
(4) population parameter
(5) reproduction parameters (e.g. spawning season, recruitment pattern)
(6) stock assessment, sustainable yield and level of exploitation

After the introduction of regulations concerning by-catch reduction devices, in 1982, research related to by-catch was developed. It included, differences in compositions of trawl catch with and without BRD, ratio of shrimp and fish catch when using BRD, by-catch species composition with and without BRD, ratio of utilised and discarded by-catch (Sadhotomo, B.; Sumiono, B., 1986; Badrudin and Karyana, 1993; Naamin. N., Sumiono, B., 1993; Widodo, J., 1991; Nasution, Ch. 1995).

4.1.2 Fishing Gear

Research on fishing gear began in 1982 with the introduction of the Turtle Excluder Device (TED) on shrimp trawl in the Arafura sea (Monintja, Daniel. R; Sujastani, T., Surachman, M., 1982). Furthermore, in 1997 research was carried out on the possibility of improving earlier model of TED (introduction of super shooter TED; Nasution, Ch., 1997).

The research was aimed at developing a type of TED that would be easy to use, would not affect the catch (fish and shrimp) and would be easily accepted by fishermen. The appropriate technology has still to be found and further experiments are required.

4.1.3 Oceanographic Condition

Several environmental factors which influence shrimp resources are rainfall, moon phase, seabed conditions, mangrove forest conditions and other oceanographic parameters. As previously mentioned, research on the environmental aspects in the Arafura waters continues to be conducted but is still insufficient.

Research was carried out on the mangrove community in Tanimbar Island (Pamudji et al, 1995), fertility levels and hydrology condition of mangrove water in Bintuni Bay (Sediadi A., Wenno, L.F., 1994) and fish community in waters surrounding mangrove in Bintuni Bay (Djamali, A. 1994). In January of 1996, a preliminary study was carried out on plankton and chlorophyll distribution patterns in the waters of Kai, Aru and Tanimbar (Sediadi, A. et al, 1991) , sediment composition in Sorong waters, Sele strait, Irian Jaya (Hermato, et al, 1987).

With regard to the abundance of shrimp resources, it was clearly found that:

(1) the mangrove is essential for shrimp resources abundance
(Martosubroto, P. 1977).

(2) dwelling shrimp species depends on the nature of the seabed (e.g. Penaeus mondon is dominant in the Aru water compared to other areas in the Arafura waters because of specific seabed condition(Naamin, N., 1987). Waters with muddy beds allow the best catch.

(3) there is no direct or indirect correlation between the rainfall average and total production, nor between the rainfall average and catch per unit of effort.

(4) the optimal water depth ranges from 20 to 30 meters.

4.1.4 Socio-economic of Shrimp Fisheries and By-catch Utilisation

Research on socio-economic aspect concerning shrimp fisheries in the Arafura Sea is still limited. However, for instance, some analysis of technico economic parameters regarding shrimp trawl fishing units show more profitability with increased number of days of fishing operation in comparison to reduced days of navigation (Damanik E.M. 1997.

Other studies were recently carried out on fish handling, marketing and by-catch utilisation. (Chasanah, E., 1998; Chasanah, E. et al, 1993; Chasanah, E. et al, 1994; Chasanah, E. et al 1995; Hanafiah, T.A.R. et al, 1994; Malawat, S. et al, 1998).

Information gathered includes:

(1) identification of the intermediates within the marketing process from producers to consumers and individual benefits from by-catch trading (It was found that the largest margin is taken by the fish broker).

(2) catch handling methods according to catch composition and characteristics (shrimp and by-catch) with the aim to reduce the discard and increases the income.

(3) processing/technology for value addition to the by-catch.

4.2 Future Research

Several points should be seriously considered:

(1) accurate fisheries data concerning biology and economic parameters is a fundamental requirement, for shrimp fisheries, in general, as well as regarding by-catch. Such information is the basis for proper management of the fisheries;

(2) conditions of the environment are essential for resources sustainability and development; consequently continuous monitoring of environmental conditions is necessary;

(3) unavoidable by-catch should be utilised to a maximum, not only for immediate profit but first and foremost to provide animal protein to the coastal community; as a result, studies concerning fish product development, including using unavoidable by-catch, should be carried out;

(4) several by-catch reduction technologies exist; the problem is to identify a technology effective in the specific local conditions and which would be accepted by the local fishery industry; additional research is required in this field;

(5) to ensure proper management and development of any fishery, a solid and rational institutional system should be established, including for correct monitoring and control of on-going fisheries (Monitoring, Control and Surveillance system, MCS).

Based on the above-mentioned points, it is concluded that relevant research programmes should include:

(1) accurate and continuous data collection through log books and observers programmes;

(2) regular monitoring of resources and environmental factors;

(3) research for improving by-catch reduction technology and by-catch product development;

(4) institutional strengthening and development for proper shrimp trawl fisheries management.


5. SHRIMP TRAWL IMPACT ANALYSIS

It is recognized that, within shrimp trawl fisheries, apart from shrimp which is the target, demersal fish (an estimate of around one hundred species (Naamin and Sumiono; 1982)) are also caught, often in large quantities, and other organisms such as crab, lobster, shrimp manthis, squid and octopus, occasionally sea snakes. It is worth mentioning that sea turtles are rarely caught because of the environmental conditions: the shrimp fishing grounds are relatively shallow, muddy and many areas with freshwater from rivers.

The additional, greatly, uncontrolled fishing effort on a large number of species other than shrimps may, of course, effect the overall resources, the ecosystem balance and the environment in general.

5.1 Impact on Shrimp Resources

The size of the shrimp caught is ranging (Sumiono and Sadhotomo, 1985; Iskandar et al, 1993) approximately 70-80 or 81-120 mm. However, it is observed that the size of the shrimp caught in Bintuni Bay and Sele is relatively small compared to the size of the same species caught in other waters.It is also observed that in the Aru watersthat the size of white shrimp is predominantly 30-40 and 41-50 (Sumiono, 1982). These seem reflecting excessive fishing and increasing fishing efforts carried out in certain areas.

Table 11 shows that fishing effort, in terms of number of days at sea, number of fishing days and number of haul from 1974 to 1996 in the Arafura waters tends to continuously increase while there is, at the same time, a sharp decrease in the average annual catch per haul.

TABLE 11. Evolution of effort and catch per unit of effort during 1974-1996 in Arafura waters

Fishing activities
per unit of vessel

1974

1977

1980

1996

1. Number of navigation days

222

247

309

308

2. Number of active fishing days

184

212

287

281

3. Number of hauling

1,342

1,561

2,238

2,303

4. Catch per hauling (kg)

95

68

40

38

Increased fishing activity was observed in the Kaimana waters during 1974-1980 and then declined during 1981-1987.

TABLE 12. Production, number of hauls and number of active shrimp fishing days in Kaimana waters


Year
Production of banana shrimp (ton, Head-on)
Number of hauling
Kg/hauling
I) 1974

872.0

12.709

69

   1975

511.1

7,097

72

   1976

958.9

16,165

59

   1977

960.9

16,847

57

   1978

788.2

14,763

53

   1979

1270.7

24,012

53

   1980

1,150.9

27,167

42

II) 1981

607.8

17,315

35

   1982

624.2

17,415

36

   1983

647.8

17,415

37

   1984

538.3

16,127

33

   1985

505.7

16,027

35

   1986

593.9

16,846

35

   1987

576.0

16,633

35

From Table 12 it can be noted that until 1980 an increase in effort was leading to an increase of total catch, while, however, catch per unit of effort tended to decrease. After a pick in 1980, the fishing effort was from 1981 -1987, at a lower level and at the same time, the catch per unit of effort. It was observed that after the pick of the fishing effort, the yield for a given effort was less than expected (57-59 kg/haul in 1976-1977 and 33-35 kg, only, in 1984-1987). This would indicate that shrimp fishing in these waters has reached the maximum level.

This observation was confirmed by Naamin, N (1984) which, when analysing data during 1974-1981, stated that, in general, white shrimp fishing, as a dominant species, has been overfished.

Table 13 presents for 1992-1995 the evolution of catch per unit of effort from one of the fishing companies which operates in the same fishing ground (Kaimana) while the fishing effort varies, with a tendency to decreasing. The yield does not really increase when the effort decrease. It probably shows that the shrimp resources have not fully recovered from past intensive exploitation.

The above interpretation most certainly depend greatly on the quality of the data and information gathered from shrimp fishing companies.

TABLE 13. Catch, number of hauls and number of active shrimp fishing days in the Kaimana waters,
from a shrimp trawler, "PT. Dwi Bina Utama"

Year

Production of banana shrimp
(kg. head-on)

Number of
Hauling

Kg/Hauling

1992

16,590

1,097

23

1993

5,818

638

14

1994

6,235

390

24

1995

9,665

723

20

Further observations during 1990-1998 in the , Aru, Kaimana, Dolak and Bintuni waters collected from the trawler "Bawal Putih II" and other outrigger trawlers, do not show for the catch per haul (an abundance index) a clear tendency (Table 14).

TABLE 14. CPUE of shrimp (kg/haul) of "R.V Bawal Putih II" shrimp trawler
and other fishing vessels during 1990-1998

Year

1990

1991

1992

1993

1994

1995

1996

1997

Aru

 

 

 

 

 

 

 

 

Other fishing vessel

-

-

 

29

25

20

26

 

BP II

20

36

 

 

37

35

35

24

Kaimana

 

 

 

 

 

 

 

 

Other fishing vessel

-

-

 

 

37

27

 

 

BP II

-

40

 

 

-

35

25

40

Dolak

 

 

 

 

 

 

 

 

Other fishing vessel

-

-

 

 

34

28

 

 

BP II

30

52

 

 

25

34

37

40

Bintuni

 

 

 

 

 

 

 

 

Other fishing vessel

-

-

 

 

35

35

 

 

BP II

20

43

 

 

-

10

-

 

For the entire Arafura waters, evolution of fishing effort, total catch and catch per unit of effort is outlined in Table 15 (for details please refer to chapter 2, fishing effort). It shows that fishing effort, which is described in number of hauls from 1990 to 1998, increases while total catch and CPUE rey2859es relatively stable.


TABLE 15. Catches, fishing effort and CPUE of shrimp trawlers
in the Arafura sea from 1990 to1998

Years

Fishing effort
(hauling)

CPUE
(kg/hauling)

Catches
(ton)

1990

632,472

33

20,872

1991

883,350

37

32,684

1992

934,192

31

28,960

1993

777,163

25

19,429

1994

851,170

28

23,848

1995

781,660

34

26,576

1996

968,371

31

30,015

1997

957,768

34

32,564

1998

977,936

30

29,338

TABLE 16. Shrimp catches composition in Bintuni, Aru, Dolak and Kaimana from 1992 to 1996

Shrimps

Bintuni

Aru

Dolak

Kaimana

 

92

93

94

95

96

92

93

94

95

96

92

93

94

95

96

92

93

94

95

96

Jerbung

76

80

71

68

83

3

5

15

22

5

10

80

48

52

33

59

46

55

43

 

Tiger

0,8

0.1

7

13

0.1

58

59

48

45

66

82

5

15

19

33

10

23

18

26

 

Dogol

23

20

21

19

17

39

35

37

33

29

8

14

37

29

33

31

31

27

30

 


Shrimp composition from several sub regions, has not changed significantly (see table 16).

Finally, it is observed that fishing gears and methods used by fishery operators do not vary much whatever the target species are, if any.

5.2 Impact on Fish Resources

Fish which is found as by-catch from trawl fishing in the Arafura sea is very important for the shrimp fishing industry. Unutilised by-catch will, most probably, greatly increase with the ever growing number of fish trawlers in the Arafura sea.

The quantity of landed fish does not only depend on the number of trawlers and fishing ground, but, also varies according to season. During the peak shrimp season, the quantity of by-catch retained tends to be minimal due to limits in fish hold capacity (see Annex 4).

The ratio of by-catch to shrimp in tropical waters is roughly estimated being, in general, about 10:1 (Allsopp, 1982). In Indonesia, several authors have presented estimations of this ratio in specific conditions: In 1981, when there were many trawlers still in operation (124 units), the ratio in Dolak, Kaimana and Aru waters was approximately 19:1 and 95% of the by-catch was utilised (Naamin and Sumiono, 1983). In 1991, when the number of trawlers operated in the Arafura sea was around 87 units, the ratio was approximately 8:1 to 13:1 (Widodo, 1991, Badrudin and Karyana, 1993). In the sub areas of Sele and Bintuni, in October to November 1992 the ratio of by-catch to shrimp was found being approximately 9:1 (Iskandar et al, 1993).

Between 1991 and 1998 data from a research vessels operating in the Arafura waters indicate that ratio fish:shrimp varies from 3:1 to 26:1, with an average of 10:1 (Table 17).

The large differences observed for this ratio probably greatly reflect the conditions on different fishing grounds exploited; however, the average still accords with the estimate given for tropical areas, in general, by Allsopp in 1982.

TABLE 17. Ratio of shrimp and fish catches by Shrimp Trawler
"RV Bawal Putih II" in Bintuni, Aru, Dolak and Kaimana

 

Bintumi

Aru

Dolak

Kaimana

 

90

91

95

96

97

98

90

91

95

96

97

98

90

91

95

96

97

98

90

91

95

96

97

98

U

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

I

3

4

 

26

 

 

9

10

6

6

9

10

7

11

21

7

25

8

 

5

 

5

8

7

5.3 Impact of Shrimp trawl Fisheries on other Organisms

As part of the by-catch in shrimp trawl fisheries, other organisms are caught in addition to fish; these consist in small sizes of shrimp, crab, squila, shrimp manthis, sea cucumber, sea snakes, starfish etc.

These other organisms are making an overall economic loss due to the following:

(1) the cost of catching these, the task of sorting them from the target catch and of discarding.

(2) the potential economic value of the discard which might be better exploited when brought to market and given value with some processing.

TABLE 18. CPUE (KG/haul) of shrimp trawler "RV. Bawal Putih II"
during 1990- 1998 in the Arafura Sea.

 

1990

1991

1995

1996

1997

1998

Aru

 

 

 

 

 

 

Fish

188

363

211

220

330

248

Shrimp

20

36

37

35

35

24

Others

16

5

11

15

26

26

Kaimara

 

 

 

 

 

 

Fish

-

189

-

176

184

189

Shrimp

-

40

-

35

25

40

Others

-

17

-

4

6

12

Dolak

 

 

 

 

 

 

Fish

199

597

517

258

934

310

Shrimp

30

52

25

34

37

40

Others

8

53

5

7

19

10

Bintuni

 

 

 

 

 

 

Fish

63

169

-

265

-

-

Shrimp

20

43

-

10

-

-

Others

2

2

-

13

-

-

TABLE 19. Landing catch of by-catch shrimp trawler in Sorong 1999

No.

Month

Catches (kg)

Remarks

1
2
3
4
5
6
7
8
9
10
11
12

January
February
March
April
May
June
July
August
September
October
November
December
--------------------------
TOTAL

97,500
101,300
107,100
93,250
91,600
109,150
96,115
98,400
110,200
99,700
101,400
93,215
--------------------------
1,198,570

Shrimp trawler company
1. PT. ALFA KURNIA
2. PT. DWI BINAUTAMA
3. PT. WIFI
4. IMPD
PT. MINA KARTIKA
PT. SAMUDRA GRAHA

5.4 Impact of Shrimp Trawl on Seabed habitat Condition

The term of seabed habitat in this context means the condition of the biotic and abiotic environment which interact amongst themselves in order to y2859etain co-existence and equilibrium in certain ecosystems, such as the coral community, mangrove, sea grasses, etc.

Bottom fishing gear, such as trawls, either directly or indirectly affect the seabed and the quality of the environment and thismay in turn disturb the equilibrium of ecosystems.

The bottom habitats in the Arafura Sea have hardly been studied, after and before the utilisation of the shrimp trawl. Research activities concerning bottom sediments, biological oceanography or coastal ecosystems such as mangrove were carried out at Benton Bay, Sele Strait and the Aru Islands. However, due to the inconsistency of time and space the information now available is very limited making it difficult to analyse the impact of shrimp trawl on the seabed and habitat conditions.

6. PERCEPTION OF SHRIMP EXPLOITATION SITUATION TODAY AND ITS IMPACT TO THE ENVIRONMENT

A survey was carried out to evaluate perception of stakeholders and local communities concerning shrimp exploitation. The results of the survey are reported below:

6.1 Perception of Industrial Group of Shrimp Fishing Operators

In general, half of the group now involved in shrimp fisheries still has a willingness to develop fleets now operating in the Arafura sea. The people in the industry consider that trawl is the most appropriate fishing gear to be used; however they consider also that the number of trawl authorized should not be increased. They consider that shrimp resource has reach an equilibrium point, and also observe that the financial aspect is on the break even point. The aforementioned shrimp fishing companies hope that Presidential Decree No. 39 of 1980 will be y2859etained or, if revised by another regulation, that the new text will allow to control trawl operations for limitating the number of vessels on each fishing ground, and will also prevent conflict with small scale fisheries using fishing gear other than trawl.

Around 38% of respondents from shrimp fishing companies stated that they always use by-catch reduction devices (or BED) as required within the Presidential Decree No. 85 of 1982; 25% stated that they use them only occasionally or were not aware whether or not they should use them (In respect to this, it is worth mentioning that only 25% believe that the use of a by-catch reduction device is an obligation while almost 38% believe that it is not); finally, 12% stated that they do not use any by-catch reduction device due to technical reasons.

67% of the people within the shrimp fishing industry consider that trawling has an impact on the biodiversity of living marine resources which is acceptable as is the rate of discard.

6.2 Perception of Non-shrimp Fishermen

Non-shrimp fishermen believe that the shrimp fishing industry should not be developed but kept as present. They agree on Presidential Decree No. 39 of 1980 about trawl banned and suggest that, for shrimp fishing, trammel net could be developed as an alternative to trawl. A few respondents consider that potential resource for shrimp is still important while others observe that the resource is decreasing.

Many non-shrimp fishermen recognize that they do not know much about the activities of the shrimp trawling industry; in particular, most of them do not know whether such fishery is still profitable or not, nor, whether fishermen use any by-catch reduction device.

This group has no idea of the number of shrimp trawlers now into operation and consequently they are not sure whether the fleet should be reduced or not. Some of the respondents consider that trawling on the bottom is very dangerous to the biodiversity of living marine resources, but, on the other hand, some others point out the fact that the damage to biodiversity is probably unavoidable. A majority of the respondents assume that discarding of by-catch when traling for shrimp is large and suggest that in order to reduce the potential negative impact certain fishing grounds should be closed.

6.3 Perception of People dealing with Environment Protection

Most of the respondents, among Environment Officers and NGO's, 83% observe that shrimp resources decrease and the same percentage consider that trawl is very dangerous for the biodiversity of living marine resources, while the rest consider that damage of biodiversity is acceptable. They assume that the ratio of discard-catch is very high within shrimp trawling fisheries and request the establishment of a closed fishing season and a reduction in the number of trawls used. Surprisingly, there is also among the same group the opinion (27%) that shrimp fishing industry can still be developed in the sea. 43% of the group consider that Presidential Decree No. 39 of 1980 regarding trawl banned should be modified.

6.4 Perception of Government Officers from the Directorate General of Fisheries

Among the staff of the Directorate General of Fisheries, around 40% consider that the shrimp fisheries industry still needs to be developed, however the same percentage think the opposite. According to them, trawl and Danish seine are the most appropriate fishing gears for catching shrimp. 50% of respondents suggest that presidential Decree No. 39 of 1980 should be abolished. They also state that by-catch reduction devices should always be used. They observed that trawling in the South East of the Arafura Sea, off Merauke (Sub-area V) is still profitable while the fishery would affect seriously the biodiversity of the resources and that the discard-catch ratio is very high. Consequently, they state that the number of trawlers in the area should be reduced. Some closure of the fishing season is also suggested as management measure.

6.5 Perception of Traders and Shrimp Exporters

Most of them belong to GAPPINDO, a fisheries businessman Organization which includes fish traders, managers of cold storage facilities and fisheries exporters. They consider that the shrimp fisheries industry can still be developed. For it, they believe that trawl is the most appropriate fishing gear to be used, however, surprisingly, they consider that Presidential Decree No. 39 of 1980 about trawl banned should be y2859etained.

They consider that shrimp potential is now exploited to its optimum and observe that the trawl industry is at its break even stages.

The majority believe that shrimp trawlers always use by-catch reduction devices when trawling for shrimp but 30% do not believe it. Only one third considers that the use of a by-catch reduction device should be compulsory while the rest that it should not be. According to a majority of the traders and shrimp exporters the impact of trawl should be acceptable, in general, and they assume that the discard-catch ratio when trawling for shimp is, in general, rather low. In term of management for the conservation of shrimp resources and environment, the group suggests to close certain fishing grounds or fishing seasons, or, to combine the two methods.

6.6 Perception of Scientists

Two third of the scientists consider that the shrimp potential yield is large while the rest recognizes that they really do not know. The later are requiring further and more complete research for assessment of the resources. The scientists observe, in general, that trawl is the proper fishing gear for exploiting shrimp resources and they consider that shrimp fishing industry can still be developed, with some increase of the number of trawlers. For that purpose, they consider that the Presidential Decree No. 39 of 1980 should be revoked.

Most of the scientists observe that by-catch reduction devices are used only occasionally by trawlers in the Arafura Sea. Around 50% of them consider that the use of such devices should be made compulsory, however, 50% recognize that the design of these should be improved.

The scientists acknowledge, in general, that trawl has a real impact on the biodiversity of living marine resources.

Most of them consider that the high discard-catch ratio when trawling for shrimp is unavoidable, but 33% observe that it is now very high. A closed fishing season, quota system of catch and regulation of catch effort are suggested as conservation measures.

6.7 Perception of Shrimp Fishing Industry in Respect to Modification of Fishing Through the Adoption of Environmentally Friendly Techniques and Practices

Environmentally friendly shrimp fishing implies fishing gear and practices which are not harmful to fisheries resources and its environment, allowing sustainable exploitation.

It is worth reminding the Ministerial Agriculture Decree, No. 02/Kpts/Um/1/1975, dated on 2 January 1975 for sustainable fisheries in the Irian Jaya waters (Arafura) which , requires:

a) all measures to keep resources sustainability in the Arafura sea.
b) closure of all fishing activities with trawl along the Irian Jaya coasts (Arafura) and all islands up to the 10m isobath line
c) no use of stretch mesh in the codend less than 30 mm
d) prohibition of all shrimp fishing activities in the Irian Jaya waters with pair trawl.
e) the number of vessel operated is regulated and adjusted every year, on 1 April, for each fish/shrimp stock.

However, the implementation of this Decree, particularly shrimp trawl industry in the Arafura Sea is not actually effective

The closure of the fishing grounds less than 10 meters in depth is not implemented and shrimp trawlers often fish in more shallow waters. In addition, it is observed that some grounds, for e.g. Benton Bay, where the average depth is more than 10 meters, are, in fact, nursery grounds which should be protected. Practically, trawling is operated in shallow waters, on some nursery grounds; the fishery community is fully aware of it but there is a lack of control, in general.

However, it is worth observing that certain areas, e.g. Paparan Sahul waters are very shallow (10 m depth is reached at more than 15 km from the coast) and, in 5 m depth, mature stages of shrimp are found.

The regulation concerning the minimal mesh size in the codend (30 mm), is not effective because, practically, codends with 45 mm meshsize still retain juvenile shrimp (21.5 mm carapace size or 3 months of age). Therefore, implementing the 30 mm mesh size regulation does not mean that no shrimp juvenile are caught (Naamin, N. 1984).

The regulation of fishing effort is fully feasible with a limitation of the number of fishing licenses, the size of vessels and number and size of nets. In addition, as already mentioned, shrimp trawlers are also required to use on their trawl some device reducing the by-catch (BED) (Presidential Decree No. 85 of 1982).

The Association of Shrimp Trawl Companies, HPPI, considers that the quantity of fish taken as by-catch when trawling for shrimp, is relatively small. It observes that for 453 shrimp trawlers operated in the Arafura Sea, the production is 34.330 tonnes/year and only 206.000 tonnes/year as a by-catch. Anyway, it is pointed out that the landings of by-catch are rather low due to operational factors and local socio-economic conditions. The operational factors include the small size of vessels (which have not enough room for storage of by-catch), the time required for handling this by-catch and short sailing times between fishing grounds and landing places (Ambon, Sorong). Socio economic factors include the decrease in the price of by-catch fish on the local market and costs for storage and transportation of it.

It is worth mentioning that recently the governor of a district, Sorong, in the North West of the Arafura Sea required that the by-catch should be landed during the peak season.; as a result, in 1999, more than 1000 tonnes of fish were landed in that district.

Regarding the utilisation of by-catch reduction devices on board vessels, the shrimp trawling operators observe that it generates a loss of shrimp catch which they estimate to about 15% for each haul; they also consider that size and design of the by-catch reduction devices should be adjusted to the size of the trawl and of the vessel on which it has to be handled (the actual devices are considered as cumbersome and creating problems when setting and hauling net).

6.8 Impact of Shrimp trawling Fisheries on Socio-economic Conditions for Local Communities

6.8.1 Employment

Shrimp trawling has brought work opportunities to local communities as for crew members and ashore, in processing, packing and exporting activities. It is worth mentioning that 3,000 people are employed at sea only in this particular industry.

6.8.2 Fishing Ground conflicts

In this respect, refeerence is made to the Ministry of Agriculture Decree No. 02/Kpts/Um/1/1975 concerning the sustainability of fishery resources development in the Irian Jaya waters which states that all trawling activities are prohibited in less than 10 meters depth.

However, shrimp trawlers often operate close to the coast (in a restricted fishing zone) even estuarine, first of all because the depth steeply increases in certain areas, even in certain estuaries..

There are frequent conflicts between local small-scale fishing communities and shrimp trawlers operating outside legal fishing zones.

6.8.3 Distribution of By-catch of Shrimp Trawl

The District Fisheries Sciences of Sorgong reports that in 1991 1.198,5 tonnes of by-catch from six shrimp trawling companies were utilised for local consumption in the North West of the Arafura Sea. (Table 19).

For this reason, the local communities there consider that:

(1) the shrimp fishing industry is important and trawling is considered as the appropriate method.
(2) the number of shrimp trawlers should be kept as it is now.
(3) the by-catch reduction (excluder) devices are used only occasionally. The fisheries communities urge that the use of this device should be made compulsory, however, they are recognizing that the design of of these devices should be improved to make sure that these do not affect the trawl operations. Relevant tests and demonstrations should be organised.
(4) it is assumed that the shrimp resource in the Arafura Sea is exploited near by its optimum. Stock assessments should be carried out within the near future.
(5) most people assume that some marine biodiversity degradation results from trawling, however, additional research should be carried out to confirm it.
(6) it is observed that trawling generates a lot of discards and considered that this should be properly reduced.
(7) closed season, closing of certain areas or fishing grounds are amongst the appropriate management measures to be applied. Controlling the fishing effort is also a necessity.

7. PROPOSED ACTION PLAN

Management plans for shrimp trawl fisheries in the Arafura sea has not yet been set up, even though it would be very suitable due to existing serious problems. According to Pollock. B. (1999) an accurate regulation for proper management is still necessary which should include Monitoring, Control and Surveillance (MCS) of fleet operations.

Such a plan should also incorporate research programmes including stock assessment, environmental aspects, post harvest and by-catch issues, socio-economic conditions, policy, consultation process, including with stakeholders.

The first step is to complete the information regarding shrimp fisheries in the Arafura sea and to find solutions. Considering the existing difficulties/problems, the issues to be considered should include:

(1) jurisdiction (including fishing authorizations), and management structures;
(2) fisheries management taking into account all aspects in a global perspective, i.e. including biological, social and economical aspects, implementation of existing regulations (in particular, utilisation of by-catch reduction devices, fishing zones, fishing license, etc.) and fish utilization and marketing;
(3) stock assessment and including monitoring of resources exploitation and survey/monitoring of related environmental parameters;
(4) Monitoring Control and Surveillance of fishing activities, MCS: relevant structures and human resources;
(5) consultation with stakeholders and extension work; consultation and coordination among government institutions;
(6) post harvest processing, in particular, for by-catch utilisation and product development.

Considering the above mentioned issues, it can already be assumed that a successful reduction in the impact of shrimp trawling on living marine resources in Indonesia, will anyway require:

(1) awareness campaign regarding negative impact from shrimp trawling;
(2) assessment of shrimp resources;
(3) assessment of the fishing technology in use and demonstration of environmentally friendly gear and practices;
(4) elaboration of the overall appropriate strategy and presentation to stakeholders;
(5) implementation procedures;
(6) data and information system regarding shrimp fishing, made at the disposal of stakeholders and National Committee members;
(7) Monitoring Control and Surveillance system, MCS.

8. CONCLUSION

1. Several assessments of shrimp resources in exploitation in the Arafura Sea have been carried out, based on the analysis of commercial fisheries. All results agree that the level of shrimp fishing has already reached a heavily exploited stage. Further more complete research is, however, still necessary.

2. The use of by-catch reduction/excluder devices is compulsory on board all trawlers in the Arafura sea. This creates problems for fishing operations and generates some loss of shrimp. In general, the fishing operators have still not perceived the benefit from using such devices. Tests on improved by-catch reduction/excluder devices and demonstration of these should be carried out.

3. To date, management of shrimp fisheries has still not been given the appropriate priority. The actual fisheries regulation is based on Fisheries Law No. 9/1985. Besides the general fishery regulation, the management of shrimp fisheries makes reference to the Presidential Decree (Keppres) No. 039/1980 and to Keppres 085/1982 which states the obligation to use by-catch reduction devices, BED, when trawling in the Arafura Sea.

4. Research activities, in particular before 1982, concerning biology and fish population dynamics have been limited so far, as well as those regarding fishing gears, environment, post harvest technology and socio-economy. Accurate and updated data on yield and effort are still missing to elaborate accompanying/routine research programmes for the development of responsible fisheries. Research budgets are limited (especially when the use of research vessels is required). Therefore, to conduct the appropriate research it is necessary to establish collaborations with the private sector in the country and with foreign research institutions (through networking). In addition, it is worth mentioning that research should, in most of the cases, be multi-disciplinary in order to get answers for complex problems.

5. The observation of the actual shrimp trawl fisheries in the Arafura Sea tends to suggest that care should be taken when exploiting these resources. Shrimp and fish resources seem to have been under high pressure for the last 30 years. Indications of resources deterioration are perceived with the size of the fish and shrimp which are smaller and smaller and the reduction in average catching yield and catch per unit of effort, in general. Apart from this, the status of environment and ecosystems cannot be properly evaluated due to insufficient data.

6. In general, shrimp trawl fisheries stakeholders are aware of the importance of reducing the by-catch and discards. They have, in principle, a positive attitude regarding the implementation of environmentally friendly technology for the sustainability of fisheries; however, only a series of tests and demonstrations on improved/new technologies will allow to increase interest and commitment of the stakeholders and lead to practical changes in the fishing practices.

7. The problems are complex and to resolve these, activities should be planned carefully. There should be first an effort for correct identification of problems, then, the design of a strategy and relevant programme and, finally careful planning of the execution of it. At the same time, it is essential keeping in mind that the shrimp fisheries stakeholders are also attempting to solve a number of related problems and that they should, therefore, be closely associated at all stages of the programme. For shrimp fisheries in the Arafura Sea, the relevant programme is already in the pipeline for the next five years and it includes the establishment of a National Committee, increasing of public awareness, the introduction of environmentally friendly fishing gear and their utilization, new assessment of shrimp potential resource, the establishment of sdata bases for scientifc purpose and networking facilities for research.

Appendix 1. List of Landing Catch of By-catch Fishes in Ambon January 1997 - June 1998

 

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