51 SURVEYS of SIAMESE CROCODILE (Crocodylus Siamensis) HABITAT in the MAHAKAM RIVER, EAST KALIMANTAN Hellen Kurniati Research

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SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN

Hellen Kurniati

Research Center for Biology-LIPI Widyasatwaloka Building Jln Raya Cibinong Km 46, Cibinong 16911 e-mail: [email protected]

ABSTRACT

Kurniati, H. 2007. Survey of Siamese crocodile (Crocodylus siamensis) habitat in the Mahakam River, East Kalimantan. Zoo Indonesia 16 (2): 51-62. A survey was undertaken to collect information on C. siamensis habitats and possible locations where C. siamensis occur in the lower Makaham River, East Kalimantan. Interviews with local villagers confirmed that C. siamensis were still encountered, and that breeding still occurs. Specific wild habitats visited (Tanah Liat, Paya, Belibis, Amir & Mesangat Lakes) had changed greatly since 1995-1996, but weeds and sedimentation were identified as impacting negatively on the habitats. Fishing pressure had increased in recent years, and young crocodiles were being caught during fishing activities. Around 360 C. siamensis were currently in captivity at two crocodile farms and in villages in the Mahakam River area. Hybridization with C. porosus had occurred on one of the farms.

Keywords: C. siamensis, habitat, Mahakam River, East Kalimantan.

ABSTRAK

Kurniati, H. 2007. Survai habitat buaya Crocodylus siamensis di Sungai Mahakam, Kalimantan Timur. Zoo Indonesia 16 (2): 51-62. Survei untuk mengetahui kondisi habitat Buaya Crocodylus siamensis telah dilakukan di daerah Sungai Mahakam bagian tengah, Kalimantan Timur. Hasil wawancara dengan penduduk lokal mengindikasikan jenis C. siamensis masih terdapat di Sungai Mahakam, dan perkembangbiakan masih terus berlanjut. Habitat spesifik untuk C. siamensis (Danau Tanah Liat, Danau Paya, Danau Amir dan Danau Mesangat) telah banyak berubah dibandingkan kondisi pada tahun 1995-1996. Gulma dan sedimentasi lumpur merupakan penyebab utama kerusakan habitat buaya C. siamensis. Tekanan dari pengambilan ikan pada habitat Buaya C. siamensis kian bertambah pada saat ini, dan anakan Buaya C. siamensis juga ikut tertangkap karena aktifitas pengambilan ikan. Sekitar 360 individu C. siamensis berada dalam penangkaran buaya di dua lokasi di Kalimantan Timur dan juga di beberapa desa di sepanjang Sungai Mahakam. Kasus kawin silang antara C. siamensis dan C. porosus telah terjadi pada salah satu penangkaran buaya di Kalimantan Timur.

Kata kunci : C. siamensis, habitat, Sungai Mahakam, Kalimantan Timur.

INTRODUCTION world’s most endangered crocodilians (Ross 1998), and is included on The Siamese crocodile (Crocodylus CITES Appendix I and is listed as siamensis) is regarded as one of the “Critically Endangered” by the IUCN-

51 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

World Conservation Union (Hilton- Kalimantan, as reported by Ross et al. Taylor 2000). The IUCN-SSC (1998; Fig. 5). Surveys in 1995 and Crocodile Specialist Group (CSG) 1996 (Ross et al. 1998) concluded that considers the conservation of C. the population was highly disjunctive, siamensis to be a high priority (SCWG and estimated that the population at 2004). that time consisted of "several hundred individuals" (Cox 2004). The Historically, C. siamensis is distributed current status of the C. siamensis in Thailand, Vietnam, Laos PDR, population is unknown (SCWG 2004), Cambodia, Indonesia and Malaysia but it is thought to be very small or (Fig. 1). However, C. siamensis is extinct (Simpson & Han 2004). probably extinct in Malaysia, and populations in Vietnam and Thailand In April 2005, the CSG Chairman, met are represented a few individuals, and with Government of Indonesia and reintroduction programs are underway crocodile industry in Jakarta. All there (Polet 2004; Temsiripong et al. participants agreed that it was 2004). Recent surveys undertaken in important for Indonesian scientists to Lao PDR suggest that the population become more involved with C. is small and fragmented (Bezuijen & siamensis (and T. schlegelii) Photitay 2005). Cambodia is conservation efforts in Indonesia, in considered the stronghold for C. partnership with the local crocodile siamensis in the region, and the wild industry. As a result of this meeting, population there is considered to this survey was planned and include less than 200 adults (Heng undertaken as a first step towards the 2004; Simpson & Han 2004). development of a future systematic survey program and conservation and In Indonesia, C. siamensis is only management plan. found in its natural habitat in the lower Mahakam River system, East

Figure 1. Distribution map of Crocodylus siamensis (yellow color) (Source: www.flmnh.ufl.edu).

52 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

MATERIALS & METHODS There were 41 C. siamensis reported Given the remoteness and small to be on the farm (14 males, 27 number of villages present and the females; Fig. 2). The owner (Mr. Tarto reported shy nature of C. siamensis Sugiarto) stated that the crocodiles (prefers not to live near people), it was were kept solely for exhibition and necessary to prioritize the display, and not for commercial locations/areas that could be visited proposes. The Siamese Crocodiles during the survey period in 9-21 June were received since 1990-1991, and 2005. were collected by local people from Muara Muntai, Bongan and Muara The specific goals of the survey were: Ancalong Villages. Muin & Ramono 1. To visit crocodile farms in (1994) reported 20 individuals of C. Balikpapan and Samarinda that siamensis on this farm in late 1993, was known to have C. siamensis, and Ross et al. (1998) reported 37 and interview the owners to individuals by September 1996 (mainly determine the origin/source of juveniles and sub-adults; Cox 2004). the crocodiles. 2. To interview local people about: The crocodiles were taken from Tanah the historical and current Liat, Belibis and Mesangat Lakes. distribution of crocodiles in areas Their average size was 1-2 m. After 14 with which they are familiar; the years in captivity, the average length types of crocodile that are of the crocodiles was about 3 m. In present in the river and lakes August, 1-2 nests were produced by near their villages; and, to learn some females in semi-natural about the daily activities of the captivities, but to date none of the local people near crocodile artificially-incubated eggs had habitats. produced hatchlings. 3. To assess potential crocodile habitats, based largely on the 2. PT Makmur Abadi Permai types of plants present in the Crocodile Farm (Samarinda) habitats, and in adjacent areas. Locations of habitats were PT Makmur Abadi Permai Crocodile positioned using GPS. Farm estimates that it had hold 314 C. 4. To identify threats that may have siamensis (180 females & 134 males; negative impacts on crocodile Fig. 3). The owner (Mr. Welly populations and their habitats. Mawengkang) could not remember the exact number of wild C. siamensis that were originally received in 1985 and RESULTS 1986, but thought it was around 200 individuals. Average size of the A. CROCODILE FARMS crocodiles was 2-3 m. Muin & Ramono (1994) reported 316 C. siamensis on In East Kalimantan there were two this farm in late 1993. crocodile farms that had collected live C. siamensis and C. porosus from the All original C. siamensis were from the Mahakam River and its tributaries. CV lower Mahakam River. The owner did Surya Raya Crocodile Farm is located not know exactly where the animals in Balikpapan and PT Makmur Abadi were collected, because some Permai Crocodile Farm is in crocodile collectors from the Mahakam Samarinda. River brought live crocodiles directly to the farm in Samarinda. 1. CV Surya Raya Crocodile Farm (Balikpapan)

53 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

Figure 2. Pure Crocodylus siamensis at CV Surya Raya Crocodile Farm in Balikpapan, East Kalimantan (Photograph: H. Kurniati).

He recalled that the villages were B. INTERVIEWS WITH LOCAL around Jempang Lake, where most of PEOPLE the collectors stay. The owner initially thought that all of his crocodiles were Based on information received from C. porosus, and had placed all of them crocodile farms in Balikpapan and (C. porosus and C. siamensis) Samarinda interviewed with local together in a semi-natural captivity. people in several villages in the The two species of crocodiles grew Mahakam River area was conducted. and bred in this breeding pond for Some local people still keep 1-3 C. about 10 years. siamensis at their homes.

Hybridization between the two species 1. Muara Muntai Village (S 000 21’ was apparent (Fig. 3). In 2000, the 40” and E 1160 23’16”) two species were separated into two different ponds. Some progeny, which In this village, a man, Mr. Sahran, kept might have been hybridizing, were three adult C. siamensis (average size placed with the parent C. siamensis of 1.5 m). He bought the crocodiles as stock. Based on an interview with the hatchlings in 1995. They originated crocodile keeper, C. siamensis lay from small lakes close to Jempang eggs between October and November, Lake. One of the crocodiles laid eggs with 30-40 eggs per nest. Only 6-7 in December 2004. nests per year were produced. The owner thought that skins and meat of 2. Bongan Village (S 000 28’ 56” and C. siamensis could not be exported. E 1160 17’25”) However, he had aware of the regulations relating to CITES This village was very close to Tanah Appendix-I animals such C. siamensis. Liat, Belibis and Amir Lakes. People in this village usually found nests, hatchlings or juvenile C. siamensis

54 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

Figure 3. Juvenile C. siamensis (hybrids?) at PT Makmur Abadi Permai Crocodile Farm, Samarinda, East Kalimantan. Notice the dorsal skin colour represent more to C. porosus with the tail ring band represents more to C. siamensis. Ventral belly skin represents more to C. porosus (Photograph: H. Kurniati).

trapped by fishhook or traditional fish River had changed drastically. Right trap (called bubu). Some people now, there were many villages along release the trapped crocodiles, but the river. others kill and eat them as they were considered to be traditional medicine 4. Benoa Baru Village (N 000 27’ 6.7” for mangy skin. If they found nests, all and E 1160 43’2.3”) of the eggs were usually taken and the infertile ones were boiled and eaten. There was one Siamese Crocodile in Siamese Crocodile nests were usually this village, which was caught 10 days located in April or May. before the survey team arrived. The 1 m long crocodile was trapped 3. Muara Ancalong Village (N 000 25’ accidentally by fishhook in Mesangat 48.6” and E 1160 40’52.6”) Lake. The owner of the crocodile wanted to keep it and waited for In this village, an old woman had one somebody to buy it, but he did not Siamese crocodile. Based on know why it was not easy to sell the interview with her, she got the animal crocodile right now. Villagers from Mentelang River about 20 years confirmed that there were many more ago. The crocodile was trapped in a crocodiles present historically, but due traditional fish trap when it was to increase boat traffic and human hatchling/juvenile. According to the settlement inside and around the large owner, the condition of the Mentelang lakes (Jempang, Semayang,

55 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

Melintang), C. siamensis seek refuge edge. Tanah Liat Lake was considered in the smaller lakes. to be in a severe condition, since 40% of the lake surface was covered by C. HABITAT ASSESSMENT Eichornia crassipes. The type of crocodile present in the lake was C. Specific areas surveyed for habitat siamensis. assessment were Tanah Liat, Paya, Belibis, Amir and Mesangat Lakes Compared to the 1995-96 survey, the (Figure 4). habitat in Tanah Liat Lake had changed significantly. In June 2005, 1. Tanah Liat Lake H. malayana and E. crassipes covered more than 50% of lake surface (Fig. Tanah Liat Lake lies at 0029’20” S 5). Local people did fishing in Tanah and 11215’48” E; elevation 0 m Liat Lake, and used many types of above sea level (asl). The size was fishing gear, including electro-fishing. considered small with an open system They know that electric fishing was around 3 km. The dominant plants harmful for juvenile fish, but continue were Hanguana malayana, to use the method as they could catch Phragmites karka and floating grass, a lot of fish with this equipment. and swamp forest was found along the

Figure 4. Site map of C. siamensis habitats in the lower Mahakam River system.

56 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 16 (2): 51 - 62

Figure 5. Comparison area of Tanah Liat Lake in 1995 (left; Photograph: J. Cox) vs. 2005 (right, Photograph: H. Kurniati), where the area had been covered densely with H. malayana and E. crassipes.

2. Paya River and Paya Lake by sedimentation of Belibis Lake. In 1996, Belibis Lake and Amir Lake Paya Lake was originally a river, and were one (Ross et al. 1998). was formed when the river became However, sedimentation separated blocked by sedimentation of mud. Belibis Lake into two parts; the new Paya Lake lies beside Tanah Liat one was now known as Amir Lake. Lake. During the survey, Paya Lake Currently Belibis and Amir Lakes could could not be enter due to low water not be entered by boat or canoe levels, and stopped at the mouth of except during high water levels. Local the lake (0027’13.6” S and people had to walk about 100 m in 11616’30.1” E; elevation 0 m asl). muddy swamp to enter the lakes. Based on interviews with local people, the habitat of Paya Lake was similar to Based on interview with the local the Paya River. In Paya Lake, people, H. malayana was the fishermen usually found hatchling or dominant plant in the two lakes. juvenile Siamese crocodiles trapped People who lived in Bongan Village by fishing gear such as fishhook or regularly went to Belibis and Amir traditional fish trap. In May 2004, a Lakes for fishing. However, since fisherman found a C. siamensis nest 2002 they did not fish in Belibis Lake in the lake. because H. malayana covers most of the water surface. 3. Belibis & Amir Lakes 4. Mesangat Lake The Belibis Lake lies in 000 27’ 21” S and 1160 17’04” E; elevation 0 m asl, Mesangat Lake lies at 0031’06” S and and Amir Lake was located beside 11641’47” E; elevation 0 m asl. Belibis Lake. Amir Lake was formed Swamp flora in this lake comprised

57 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62 mainly H. malayana, Leersia structure considerably. The process of hexandra, Thoracostachyum sedimentation was accelerated with sumatranum and Scleria spp. the growth of weeds. Belibis Lake Mesangat Lake was categorized as was one of the C. siamensis habitats good habitat since the habitat had not where weeds and mud sedimentation been extensively damaged. However, had "dried up" the lake, preventing based on the observations Mesangat access except during periods of high Lake was not a typical lake, but was water levels. Weeds and rather like a large freshwater swamp. sedimentation had also been Almost the entire water surface was impacting on Tanah Liat, Paya, Amir covered with floating plants. and Mesangat Lakes. The number of fishermen in the Mahakam River was Based on interviews with local people, increasing, due to increasing numbers there were two species of crocodiles in of villagers and also due to an influx of Mesangat Lake, namely C. siamensis new people from other areas. and Tomistoma schlegelii. During the visit to the lake, one possible C. 2. Indirect Threats siamensis nest was found. A fisherman (Bapak Yus) explained that Although the Indonesian Government C. siamensis (or Buaya Badas Hitam) had closed several logging companies usually build nests among grassy in the upper Mahakam River, however, areas or H. malayana, whereas T. illegal logging still continues. schlegelii (or Buaya Sapit) build nests Interviewees believe that high flood in the forest (forest means land with levels over the last 3-4 years during many big trees). The habitat in the rainy season were caused by Mesangat Lake had almost never forest degradation in the upper changed. However, the number of Mahakam River. It was unclear people fishing in this lake had whether there was a relationship increased 3-fold since 1996, to about between logging and increased 50 fishermen. flooding, but certainly increased sediment in floodwaters due to erosion D. THREATS might be a result of logging. This had a negative impact on the people living More than half of the local people in in the lower Mahakam River through lower Mahakam River are fishermen. habitat change. The Siamese They knew that Siamese Crocodile Crocodile was potentially affected by habitats were a source of fish, and that this also. Floodwaters invaded human floating plants were home of juvenile settlements and cover crocodile nests, fish. To their knowledge, most of the resulting in crocodile egg mortality. habitats surveyed in 1995-1996 had not changed. Nevertheless, several threats that were gradually destroying DISCUSSION the habitats were identified. These threats were categorized as "direct" or This survey confirmed previous "indirect". reports (Ross et al. 1998) that Mesangat Lake consists of stable 1. Direct Threats permanent water. There were no serious threats of weeds and mud Hanguana malayana and E. crassipes sedimentation so far, although fishing (water hyacinth; introduced from South pressure had increased over the last America), fishing activities and mud decade. Both C. siamensis and T. sedimentation had been impacting C. schlegelii were reported to be present siamensis habitat. Weeds were in this lake. This lake represented the natural enemy for crocodile habitats, least disturbed habitat visited during with the capacity to change the floral the survey.

58 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

Mesangat Lake was an isolated lake, villager had a crocodile that had been and was not affected by water flows obtained 20 years ago, and one C. associated with the Mahakam River. siamensis was caught as recently as On the other hand, Tanah Liat Lake 10 days before this survey was and nearby lakes received water from undertaken. the river, which contains sediment, especially in the rainy season. As a Captive breeding had not been result of sedimentation, large areas of successful at one of the farms visited, water were now covered by invasive and only infertile eggs were produced plants such as H. malayana and E. (see Cox 2004). There had been crassipes. One fisherman indicated limited success at another farm, but that C. siamensis might use H. adult C. siamensis and C. porosus malayana for nesting, but the long- were housed in a common pond, and term impacts of the changes in there had been hybrid offspring vegetation on the habitats were produced. The C. siamensis on the unknown. crocodile farms represent a significant source of adult stock that could be None of the principal habitats of used to produce crocodiles for re- Siamese Crocodile in the lower stocking, should that prove to be a Mahakam River were protected. strategy to adopt in the future. Care Wetland International-Indonesia should be taken to ensure that Program had proposed Mesangat hybridization was controlled, and if Lake, together with other lakes in possible eliminated. The separation of Mahakam River system (Jempang, adult C. siamensis and C. porosus at Semayang & Melintang), to be fully the farm where hybrids were protected (Wibowo 1997). However, encountered is a step in the right Forestry Department of Indonesian direction. Phenotypic characteristics Government had not approved the alone were unable to separate hybrid proposal. Most of the people in the C. rhombifer-C. siamensis hybrids lower Mahakam River were fishermen. from pure C. siamensis in Vietnam, Numerous waterways in crocodile and DNA testing were required to habitats were fished intensively with establish identity (N. Fitzsimmons fishing nets, hooks and fish traps. pers. comm.). Genetic testing would These types of equipment catch probably be required in Kalimantan for hatchlings and juvenile crocodiles. possible future re-stocking of depleted The use of electro-fishing equipment populations. might also had a detrimental effect on the crocodile population. Overall, pressure on the existing C. siamensis habitat was high, and it In Indonesia, C. siamensis was might not be easy to minimize the protected under Indonesian Law UU threats caused by activities of local No. 5/1990 and PP No. 7 & No. people. Community based 8/1999 (Departemen Kehutanan conservation was a possible 2003), and all activities related to the conservation strategy which might be commerce of this species were suitable for the local community in the prohibited. This was not clear to local Mahakam River area. As had been people and also to some of the local shown in other countries, long-term crocodile industry members. For conservation might be depended on example, Muin & Ramono (1994) some form of use. reported four C. siamensis and six T. schlegelii being held by a villager at This survey had confirmed that C. Muara Muntai Village in 1993. We siamensis were still present in the interviewed a villager in the same upper Makaham River, and breeding village, who had three C. siamensis still occurs. However, more detailed that he had obtained in 1995. One systematic surveys over a wider area

59 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62 were required to assess the current Gland, Switzerland and status of the wild C. siamensis Cambridge. UK. population. Muin, A. & W.S. Ramono. 1994. Preliminary suevey of Buaya sumpit (Tomistoma schlegelii) ACKNOWLEDGMENTS and Buaya Kodok (Crocodylus siamensis) in East Kalimantan. Special thanks are given to Mr. ACSUG report. Rachmat Wiryadinata of PT Ekanindya Polet, G. 2004. Re-establishment of Karsa who sponsored this survey Crocodylus siamensis in Cat without any benefits for his company. Tien National Park, Vietnam. Many thanks are also given to Mr. Crocodile Specialist Group Tarto Sugiarto of CV Surya Raya and Newsletter 23(4): 12-16. Mr. Welly Mawengkang of PT Makmur Ross, J.P. 1998. Crocodiles. Status Abadi Permai for their assistance survey and conservation Action during our visit to their crocodile farms. Plan. 2nd Edition. IUCN/SSC Finally, many thanks are given to all of Crocodile Specialist Group. field assistants who helped us in the IUCN, Gland, Switzerland and preparation on this document. Cambridge, UK. Ross, C.A., J. Cox, H. Kurniati & S. Frazier. 1998. Preliminary REFERENCES survey of palustrine crocodiles in Kalimantan. Pp 46-79. in Bezuijen, M. & C. Photitay. 2005. Crocodiles. Proceeding of the Siamese crocodile surveys in 14th Working Meeting of the Lao PDR find hatchlings. IUCN-SSC Crocodile Specialist Crocodile Specialist Group Group. Singapore. IUCN: Newsletter 24(2): 10-11. Gland. Cox, J.H. 2004. Status and Siamese Crocodile Working Group conservation of the Siamese (SCWG). 2004. Siamese crocodile Crocodylus siamensis Crocodile Working Group in Kalimantan (Indonesian meeting, 24-28 May 2004. Borneo). Pp 150-154. In Crocodile Specialist Group Crocodiles. Proceedings of the Newsletter 23(4): 18-20. 17th Working Meeting of the Simpson, B.K. & S. Han. 2004. IUCN-SSC Crocodile Specialist Siamese crocodile (Crocodylus Group. Darwin. IUCN: Gland. siamensis) surveys in CSGN, 2005. Editorial. Crocodile Cambodia. Pp 110-120. In Specialist Group Newsletter Crocodiles. Proceeding of the 24(1): 3. 17th Working Meeting Departemen Kehutatan. 2003. Crocodile of the IUCN-SSC Kumpulan Peraturan Crocodile Specialist Group. Perundangan Bidang Darwin. IUCN: Gland. Konservasi. Departemen Temsiripong, Y., P. Ratanakorn & B. Kuhutanan-JICA. Jakarta. Kullavanijaya. 2004. Heng, S. 2004. The conservation of Management of the Siamese Siamese crocodile in crocodile in Thailand. Pp 141- Cambodia. Pp 148-149. In 142. In Crocodiles. Proceeding Crocodiles. Proceeding of the of the 17th Working Meeting 17th Working Meeting Crocodile of the IUCN-SSC Crocodile of the IUCN-SSC Crocodile Specialist Group. Crocodile Specialist Group. Darwin. IUCN: Gland. Darwin. IUCN: Gland. Wibowo, P. 1997. Hasil temuan survey Hilton-Taylor, C.. 2000. IUCN Red List lahan basah di Kalimantan In: of Threatened Species. IUCN. Seminar Pemaparan Hasil-

60 SURVEYS OF SIAMESE CROCODILE (Crocodylus siamensis) HABITAT IN THE MAHAKAM RIVER, EAST KALIMANTAN: Zoo Indonesia 2007. 16(2): 51-62

hasil Temuan Teknis Proyek UK-Indonesia Dibidang Pengelolaan Hutan Tropis di Indonesia: Sub-proyek Konservasi Suaka Margasatwa Danau Sentarum (1992-1997) Bogor, 16-17 Juni 1997. Wetlands International- Indonesia Programme. Bogor : 1-9.

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