INTERACTION OF SEA TURTLES WITH INDONESIAN FISHERIES – PRELIMINARY FINDINGS
IMAM MUSTHOFA ZAINUDIN1, LIDA PET-SOEDE2, CREUSA HITIPEUW3 and WINDYA ADNYANA4
WWF-Indonesia,
Jl. Mega Kuningan lot 8.9/A9
Kawasan Mega Kuningan
Jakarta 12950, Indonesia
Email: 1. imusthofa@wwf.or.id, 2.Lpet@wallacea.wwf.or.id,
3. chitipeuw@wwf.or.id, 4. wadnyana@wwf.or.id
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Introduction
Six of the world’s seven turtle species are found in Indonesia: leatherbacks, greens, hawksbills, olive ridleys, loggerheads and flatbacks. With its numerous islands, extensive coastline, vast areas of sea grass beds and coral reefs, Indonesia provides important nesting and foraging grounds to sea turtles. Indonesia hosts the largest rookery for green turtles recorded in Southeast Asia, in the Berau Islands, East Kalimantan, and the largest nesting rookery for leatherback turtles located along the northern coast of Papua. Each season between 1,865-3,601 nests are recorded at Jamursba-Medi and 2,881 nests at Wermon (Hitipeuw et al, 2007). Satellite tracking data and tracing records of flipper tags indicate that these greens and leatherbacks migrate very large distances over open waters from their nesting grounds to get to their feeding grounds. These sea turtles face various threats while they are in Indonesian territory. Supporting the Indonesian government in their implementation of laws and regulations (Table 1), WWF-Indonesia has taken a strategic approach towards turtle conservation which includes:
- Habitat protection for green and hawksbill turtles mostly in Berau District, East Kalimantan and for leatherback and olive ridley turtles at Jamursba Medi, Papua.
- Reducing direct take in the turtle trade mostly in Bali in the traditional hunting for leatherback at the Kei Islands – Maluku.
- Reducing indirect take – by-catch, mostly in the tuna fisheries, the shrimp fisheries and some coastal fisheries.
- Support enabling policy, mostly through the facilitation of local, national and international meetings and campaigns.
There were three main reasons for the WWF involvement in assessing the interactions between Indonesian fisheries and sea turtles through observer programmes:
- In a previous FAO expert meeting, the potential significant threat of by-catch on already collapsing leatherback turtle populations was discussed and WWF decided to start collecting information for Indonesia. Only anecdotal evidence existed, very little was published on the issue and while the Indonesian government had mandated the use of Turtle Excluder Devices (TEDs) in the shrimp trawling since many years, previous NOAA (National Oceanic & Atmospheric Administration, US Dept. of commerce) studies indicated that the application of TEDs is very low.
- NOAA provided WWF with grant support to start training tuna long-line fishing crews in proper release of hooked turtles. WWF had no information on how many turtles were hooked and in what area, and needed to collate information to allow a selection of training participants.
- Also, the Indonesian government started taking a more active role in regional initiatives, and signed the IOSEA MOU (Indian Ocean South- East Asia Sea Turtle Memorandum of Understanding) in March 2005 in Bangkok, formalised the Sulu Sulawesi Marine Eco-region tri-national agreement in March 2006 in East Kalimantan, and signed the Bismarck Solomon Seas Eco-region MOU on leatherback conservation in September 2006 in Bali. Indonesia is also preparing to sign up as full member for Regional Fisheries Management Organisations (RFMOs) especially for the IOTC (Indian Ocean Tuna Commission) and WCPFC (Western & Central Pacific Fisheries Commission). To fulfil information requirements for the RFMOs and other international and regional initiatives, Indonesian data on by-catch, total catch and geographical fishing patterns are needed. The system of on-board log-books introduced in the late 1970s is not well implemented.
National action on reducing by-catch in the Indonesian tuna long-line fishery was initiated on June 7, 2005. A public consultation was held in Denpasar, Bali that resulted in a joined declaration and national action plan for addressing by-catch with coordination by the Research Centre for Capture Fisheries of the Ministry of Marine Affairs and Fisheries and supported by Indonesian stakeholders including the tuna. This paper summarises preliminary findings of the occurrence of by-catch and mitigation efforts taken
since 2005.
Table 1: Relevant regulations for sea turtle conservation in Indonesia
|
Relevant national decrees |
Year |
Remarks |
|
Presidential |
1978 |
Ratification |
|
Ministerial |
1978 |
Determination |
|
Ministerial |
1980 |
Determination |
|
Act |
1982 |
Basic |
|
Presidential |
1986 |
Ratification |
|
Act |
1990 |
Conservation |
|
Presidential |
1990 |
Management |
|
Ministerial |
1992 |
Protection |
|
Act |
1994 |
Ratification |
|
Ministerial |
1996 |
Protection |
|
Government |
1999 |
Protection |
Methods
Validation and up-to-date information on occurrence of sea turtles as by-catch in Indonesia’s fishery was needed to assess the importance of the issue and to find the best strategy for reducing by-catch. We interviewed fishermen and initiated an on-board observer programme.
Interviewing fishermen
There were long debates among stakeholders on the occurrence of by-catch in the Indonesian fishery. WWF worked with research institutions and local NGOs in Indonesia on a fisher survey using semi-structured interviews. The survey found that there were interactions between sea turtles and several types of fishing gears. The fishermen often spotted sea turtles during their fishing activities and this indicates that their fishing grounds overlap with migratory routes for sea turtles.
Most respondents admitted that they caught sea turtles during fishing, at least one animal in their most recent trip (Appendix 1). They did not think it was a big problem, but considering the large fleet, a minimum of one animal per trip per vessel results in a large number of interactions throughout the year. From the survey it was also clear that all respondents were willing to release the turtles, and this allowed us to start training on proper handling methods of entangled and hooked sea turtles.
On-board observers
To validate the information from the interviews, WWF also implemented an on-board observer trial in the tuna long-line fleet and shrimp trawl. In the first year, WWF needed to learn how to best implement on-board observer activities and developed the method and simple protocols together with volunteers from the fisheries academy in Sorong. Based on the information collected in the first year, WWF started a formal on-board observer programme in May 2006. The on-board observers collect data on tuna and shrimp fisheries and their interactions with protected and endangered marine species (e.g. sea turtles, marine mammals, sea birds and sharks.
Observer findings in the tuna long-line fleet
For the tuna long-line observer programme, WWF collaborates with the Research Centre for Capture Fisheries (PRPT). The on-board observers are well accepted and supported by the Indonesian Tuna Long-line Association (ATLI), the Indonesian Tuna Association (ASTUIN) as well as by other individual tuna long-line industry members. From May to December 2006, there were two observers in Bitung, North Sulawesi on-board two vessels, two observers in Pelabuhan Ratu-West Java on-board three different vessels, and in Benoa-Bali we have two observers and two boat captains who observe on five vessels. The resulting data set includes 539 sets of these 10 vessels that operated in the Indian Ocean, the Pacific Ocean and in the territorial waters of Indonesia (Figure 1).
Figure 1: Map of the region where the observer programme was conducted with the results of the findings.
Many of Indonesia’s tuna long-line vessels operate outside of the Exclusive Economic Zone of Indonesia (Figure 1). Recent efforts by the Indonesian Government to join with full membership the IOTC and the WCPFC are thus correct and are supported by the industry. It also emphasises that Indonesia must stay active in regional approaches to sea turtle conservation, as by-catch of sea turtles is a global issue.
Data collected between May and December 2006 show that 832,208 hooks caught 85 sea turtles, one whale, two dolphins, two sea birds and 507 sharks. Except for sharks, which are valuable for their fins, all animals were released back to the sea. Five of the sea turtles were dead. Based on their hook rate of 0.225 per 1,000 hooks, the tuna long-line fleets from Bitung-North Sulawesi caught the most turtles, followed by Pelabuhan Ratu-West Java with 0.034 takes and Benoa-Bali with 0.031 (Table 2). Most of the Bitung tuna long-line fleet fishes in the Pacific; they usually use shallow settings with 7 to 10 hooks between one float. They use various types of baits during one trip, including milkfish, squid and scads. Shallow setting and using squid and scads for the bait were predicted to result in many turtles being hooked in tuna long-line gears. The fleet from Benoa-Bali mostly uses sardines as bait and set their lines deeper as they target big-eye tuna.
Olive ridley turtles dominate the turtle by-catch and all animals captured were adults (see Figure 2 and 3 respectively) and most were males (Table 2). Sea turtles hooked in the Pacific represent a larger variety of species than those hooked in the Indian Ocean and Banda-Flores Sea (Figure 4). Migration of leatherback turtles is mainly through the Pacific and long-lines operate near leatherback, hawksbill and green turtle feeding and nesting areas.
Figure 2: Number of turtles hooked in tuna long-line gear recorded by observers between May-Dec 2006
Figure 3: Size of turtles hooked in tuna long-line gear (Curved Carapace Length – CCL)
Our total number of observers on-board tuna long-line vessels is still limited and focussed on the fleet operating from Bitung-North Sulawesi operating in the Pacific, the fleet from Benoa-Bali operating in the Indian Ocean and territorial Indonesian waters such as the Banda Sea and the Flores Sea. This work needs to be expanded.
Table 2: Summary data from observers for May-December 2006.
Figure 4: Location of occurrence of sea turtle by-catch during May-December 2006
Observer findings in the shrimp trawl fleet
For the shrimp trawl observer programme, WWF collaborated with Marine and Fisheries Agency of Sorong and also with the Fisheries Academy, Sorong. On-board observations in 2005 revealed that sea turtles are often caught in the trawls that mostly operate in the Arafura Sea. Between two to 33 sea turtles were caught in 12 shrimp trawls, with an average of 11 turtles per vessel (Table 3). Boat crews confirmed the finding and admitted that, on average, 2-20 sea turtles were incidentally caught during the trawl operations. Although most sea turtles caught were olive ridleys (14), green turtles (eight), and loggerheads (four), the occasional by-catch of hawksbill turtles also occurred (Table 3). Sometimes, leatherbacks were trapped in their nets. This frequent interaction confirms that the Arafura Sea and adjacent waters are important migratory routes for turtles.
Almost all captured animals were released to sea – 98.5 per cent (2005) and 100 per cent (2006), and only 1.5 per cent of the animals (2005) were kept for consumption (Table 3). While the capture rates are high, almost all incidentally caught sea turtles were released back to the sea for several reasons: (1) crews were aware of the prohibition of sea turtle exploitation, (2) the large size of some captured animals made it difficult to pull the animals aboard, there is limited space on-board to keep the meat or there is a belief that sea turtles on-board would reduce potential catch. The main reason for the high number of animals caught is the lack of inclination to install TEDs (Turtle Excluder Devices) in their trawlers, as they believe that this would reduce the fish by-catch. Usually, boat crews are entitled to take and sell any fish by-catch as bonus and this additional income turns out to be higher than their monthly wages. This should be addressed when aiming to improve the application of TEDs, BEDs (By-catch Excluder Devices), and JTEDs (Juvenile Turtle Excluder Devices). Unless this is tackled, it is highly unlikely that the shrimp trawler industries will implement the regulations.
Table 3: Summary of observer data in shrimp trawl vessels (2005 and 2006)
The Circle Hook Trial
With technical advice of NOAA-NMFS, WWF started a circle hook trial in Indonesia. The trial is scheduled for the 4 major tuna long-line fleets in Indonesia, Pelabuhan Ratu-West Java, Cilacap-Central Java, Benoa-Bali, and Bitung North Sulawesi. The trial aims to compare the turtle capture rates for circle hooks (size C16/0) and normal tuna hooks used by Indonesian long-liners.
There were major challenges trying to engage fishermen in the trial. Many fishermen doubted whether they would catch any fish and comments included:
- The circle hooks sizes are bigger compared to their hooks.
- Their bait is too small for the circle hooks; they are afraid that their bait will fall off.
- They were not convinced that the new hooks would catch as much fish as the old hooks.
After working to convince captains and crews over a long time, in December 2006, one captain in Benoa-Bali agreed to try the circle hooks and on December 20, he left the harbour with 1,000 circle hooks and 1,000 normal hooks. In the first 10 sets, the circle hooks showed better catch than the normal hooks with 10 tuna in circle hooks and seven tuna in normal hooks. After 36 sets, at the end of his trip the circle hooks had caught 53.5 per cent of the total catch and captured no turtles while the usual hooks accounted for 46.5 per cent of the total catch and hooked one olive ridley turtle (Table 4 and 5). Also, during this trip, the circles hook caught 12.1 per cent more target fish and 14.63 per cent less discards than the normal hooks. More big eye tuna were caught with the circle hooks.
The captain communicated these results to other tuna long-line vessels via radio and now, 4 vessels in Benoa-Bali use circle hooks; a total of 3,500 circle hooks. More vessels wanted to use circle hooks, but we did not have stock, and are currently trying to get additional circle hooks. These very preliminary results show that circle hooks could be one important way to reduce by-catch but this research needs to be continued and expanded to other countries as well. The availability of circle hooks is also an issue.
Table 4: Catch composition
Table 5: Summary of the circle hook experiment
Conclusions and recommendations
The Indonesian long-liners try to minimise interaction with turtles as they believe that sea turtles on-board will reduce their catch. Also, if the vessel’s captain is Chinese or Taiwanese, they always release the turtles as they believe that sea turtles are divine creatures and must be respected. Our observers have an important role to play here to ensure that turtles are released properly. With their guidance and proper use of de-hookers, observers can increase the survival of turtles significantly. Also, the observers are the best individuals to conduct general awareness and training activities as they spent several months together on-board. Observers can utilise the crew’s natural curiosity to talk about nature and best practices. Training and outreach onshore is difficult as most crews are away for long periods of time and want to spend time with their families. Tackling the issue of low compliance with installing TEDs on shrimp trawl vessels requires a different approach. The financial incentive is too high to leave the TEDs unused as the fixed salaries are very low.
The observer programme must be expanded and could be formally adopted by the Indonesian Government. Students from fisheries academies throughout Indonesia could be very suitable observers as they have the ability to work on vessels for long periods of time under harsh conditions. The gear trial with circle hooks must also be expanded to include more vessels fishing in other areas
Acknowledgements: The authors wish to thank NOAA-PIRO (Pacific Islands Region), NOAA-NMFS(National Marine Fisheries Service) and WWF U.S. for their support of this project, the Research Centre for Capture Fisheries (PRPT), Marine and Fisheries Agency of Sorong, Fisheries Academy of Sorong for their collaboration, the observer coordinators (Priyanto Rahardjo, Karel Takaendengan and Soehartoyo) and all the observers in Sorong, Bitung, Pelabuhan Ratu and Benoa-Bali. Many thanks are due to the members of the tuna long-line and shrimp trawl industry for their trust and collaboration, especially to ASTUIN (Indonesia Tuna Association) and ATLI (Indonesia Tuna Longline Association). A hanks to the TAKA Foundation and students of Udayana University for their work. This paper was presented at the SEAFDEC-FAO Workshop on assessing the relative importance of sea turtle mortality due to fisheries in Southeast Asia, Bangkok; 19-23 March 2007.
Literature Cited
Adnyana, I.B.W. 2006. WWF Technical Progress Report for Sea Turtle Program per July-December 2006. (unpublished)
Habibi, A., A.H., Adyas, R., Firdaus, 2006. Study Of By-Catch Status In Indonesian Capture Fisheries-Especially Interaction Protected Marine Species And Fishery In Java. TAKA Foundation. Semarang (in Bahasa Indonesia).
Hitipeuw, C., L., Pet-Soede, 2005. A Need to Align and Integrate Incentive Strategies. Lessons Learned from Turtle Protection in Eastern Indonesia. WWFIndonesia. Papers presented at the Expert consultation on Interactions between Sea Turtles and Fisheries-FAO, Rome.
Hitipeuw, C., H.P., Dutton, S., Benson, J., Thebu, and J. Bakarbessy, 2007. Population Status and Inter-nesting Movement of Leatherback Turtles, Dermochelys coriacea, Nesting on the Northwest Coast of Papua, Indonesia. Chelonian Conservation and Biology 6(1).
Takaendengan, K., N., Manik, P., Makatipu, M., Jabar, S., Wouthuyzen, A., Umar, J., Picasouw, I., Raharusun, 2005. Sea Turtle By-Catch on Longline Fisheries in Indonesia. Indonesia Science Institute (LIPI). Bitung.
Musthofa Zainudin, I. 2005. Possible Interactions of Sea Turtles with Shrimp Trawl Fisheries in Sorong-Papua and Tuna Long-line Fisheries in Benoa – Bali. Data from field observations, November 2005. WWF-Indonesia report. 41pp.
Musthofa Zainudin, I., and C., Pet-Soede, 2005. By-catch in Indonesian Fisheries – A desk study,
WWF-Indonesia report. 39pp.
Appendix 1: Information on sea turtle interactions in various fishing gears in Indonesia (result from interviews with fishermen)
