(Appendix B1) INO: Sarulla Geothermal Power Generation Project

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Environmental Management Plan (Appendix B1)

Project Number: 42916-014 March 2019

INO: Sarulla Geothermal Power Generation Project

Prepared by Sarulla Operations Limited

The environmental management plan is a document of the borrower. The views expressed herein do not necessarily represent those of ADB's Board of Directors, Management, or staff, and may be preliminary in nature. Your attention is directed to the “Terms of Use” section of this website.

In preparing any country program or strategy, financing any project, or by making any designation of or reference to a particular territory or geographic area in this document, the Asian Development Bank does not intend to make any judgments as to the legal or other status of any territory or area. Final Report

Biodiversity Monitoring: Stage 1

Camera trapping and Wildlife Surveys

A rare picture of a Manis pangolin ( javanica), listed as Endangered on the IUCN Red List and protected under Indonesian law, together with a Barking deer Muntiacus ( muntjac) also a protected species, caught together on camera trap at SOL.

7th of July 2014 by PanEco/YayasanEkosistem Lestari

requested by

Sarulla Operations Ltd.

Executive Summary

As part of evelopment the d of a Biodiversity Action Plan (BAP), biodiversity surveys consisting of camera trapping and specific primate/sun bear sign surveys were carried out between November -‐ 2013 June 2014 in the forest area where Sarulla Operations Limited (SOL) is developing a -‐ large scale geothermal project in/adjacent to the Batang Toru forest complex, located in North Tapanuli, North Sumatra, Indonesia. These Stage 1 biodiversity surveys were intended to biodiversity provide baseline data in the SOL project area prior to disturbance activities and aimed to cover a combination of habitat types and locations within the forest areas near NIL1 and WJP1. Unfortunately land ring clea activities had already commenced towards the end of July 2013, before camera trapping/wildlife surveys were started. These land clearing activities, as well as high human presence and the sound of chainsaws from various legal angles (both SOL and il logging), might have affected various mammal species living in the area. For instance, pecies s not living in strict territories are likely to have moved away from the disturbance. Other species might have been affected by the increase ivity in human act in the area through increased hunting pressures.

Key findings

¡ A total of 27 mammal species were encountered during the y biodiversit surveys in and around the SOL project area between -‐ November 2013 June 2014. Of these, 11 mammal species are listed under the IUCN Red List as Critically Endangered, Endangered or Vulnerable, and 15 of these species are protected under Indonesian law;

¡ A Sumatran tiger (Panthera tigris sumatrae, IUCN Critically Endangered, CR) scat containing pangolin scales was encountered during the reconnaissance surveys in November 2013;

¡ Sumatran orangutan Pongo ( abelii, CR) nests (5 nests) aged 1-‐6 months old were encountered in June 2014 <2 at some .5 km distance from the NIL1 site and WJP location;

¡ Pangolins (Manis javanica, EN) were photographed at 3 locations in the SOL area;

¡ Marbled cat Pardofelis ( marmorata, EN) was caught on camera trap in 2 separate locations;

¡ Density f o resident agile gibbon (Hylobates agilis, EN) groups was found to 17.9 be high ( ind/km2) in the SOL project area;

¡ Siamangs Symphalangus ( syndactylus, EN) were observed and 2 groups mapped during the surveys;

¡ Mitred leaf monkeys Presbytis ( melalophos, EN) were directly observed twice times during the surveys;

¡ Pig-‐tailed macaques Macaca ( nemestrina, VU) were one of the most common species caught on camera traps;

¡ Sun bear Helarctos ( malayanus, VU) sign (claw marks and feeding sign) was encountered throughout the SOL area;

¡ Sambar deer (Cervus unicolor, VU) including several female with young were caught on camera trap on 31 independent events;

¡ Tiger prey species (sambar, barking deer, pigs, and pig-‐tailed macaques) were among the most common mammal species caught on camera traps in the area;

¡ Hunters and dogs were caught on camera eparate traps on 23 s occasions.

¡ Although not investigated as part of the current ea surveys, the SOL ar has a rich floral diversity, including several protected species including pitcher plants Nepenthes ( spp.) and many orchid species.

Recommendations

Due to the high occurrence of a significant number of IUCN Red Listed species as well as wildlife protected under Indonesian law in the SOL project area, we provide the following recommendations:

Connectivity: Any new road construction in forested areas [to WJP 1] should maintain as many as possible locations along the road where arboreal connectivity [< 5 meter gap] is maintained. This will enable arboreal primates (gibbons, siamang, orangutans, nkeys) mitred leaf mo to continue to use their home ranges that might be dissected by road development. The absolute maximum distance between uch s arboreal connectivity should be 250 meters along the road, and preferably less than . this

Hunting: Hunting of wildlife, including protected species and poaching of songbirds, is common throughout the SOL project area, and several are recommendations made:

¡ Limit/halt free access using project roads;

¡ Develop onservation/hunting c agreements focusing on protected species with the main villages/hamlets close to the project area, and in return provide support for developing small enterprises that will provide sustainable protein alternatives such ( as fish ponds, chicken farming, pig farming);

Illegal Logging: Illegal logging around the SOL project area was encountered in several locations and should be halted. The high occurrence of illegal logging in the area is most likely related to the road access, as cut timber is taken out over the road.

Garbage Management: Large amounts of daily (food packaging) rubbish were being disposed of randomly in the forest by SOL staff (water bottles, cigarette pack/butts, lunch packaging, plastic bags etc).

Instructions to staff and control measures should be put in place to stop this littering, and previous litter should be picked up from throughout the SOL project area.

¡ Any other human disturbance , (i.e. noise motorbikes, music), as well as dogs, cats, and invasive species should be minimized as much as possible;

¡ Strict regulations should be put in place regarding the above, both for SOL workers, contractors, visitors and local communities passing through the area;

¡ More in depth baseline information/surveys and monitoring, specifically botanical, but also birds and reptile/amphibians, are recommended to better understand the overall ecology of the area, and to develop a better understanding how to mitigate development activities to other species of ion conservat interest occurring in the ; SOL area

General Comments: Because of its scale and importance to the local economy, SOL is perfectly placed to introduce improved environmental practices by implementing the above recommendations for prevention of hunting of protected wildlife, illegal logging, and garbage management. While the company may feel it maintains the support of local communities by bowing to pressure to allow open access to the forests es, surrounding its worksit in the long term this policy can ebound r on the company as its practices become more widely known. On the other hand, rigorously imposing best practices on its own workforce and dissemination of these amongst local communities will enhance the company's international reputation, provide a strong case study for other companies sia, operating in Indone and modify environmentally damaging practices by local communities that appear to currently be accelerating around the work sites.

Furthermore, the company is building a relatively lly environmenta -‐friendly energy power plant that will have local impacts on the highly biodiverse and unique Batang Toru forests. But it has the opportunity to play a very important role in the long-‐term conservation of the wider tang Ba Toru forest complex ast (both E and West blocks), thus further demonstrating a wider commitment to environmental best practices and conservation.

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Credits Report prepared by PanEco/YayasanEkosistem Lestari:

• Gabriella M. Fredriksson, • Graham Usher, • Matthew G. Nowak;

Field data lection col & survey teams:

• Ronald Siagian (Camera trapping) • Sugesti Mhd Arif (Primate surveys) • Mokhamad Faesal Khakim (Sun bear surveys) • Irvan Sipayung (Survey team) • Hermansyah (Survey team) • Roma Irama (Survey team) • Kamarudin (Survey team) • Sumurudin (Survey team)

Acknowledgements We would like to express our gratitude L to all the SO field workers who joined the various surveys and camera trapping efforts, SOL management team in Sarulla for logistical support, Dave Dellatore and Wie Siong (Aerial Surveys), Iain Bray (Mott McDonald) and Jess McKelson.

Contents Executive Summary ...... i Key findings ...... i Recommendations ...... ii Credits ...... iv Acknowledgements ...... iv List of Figures ...... vi List of Tables ...... viii 1. Introduction ...... 1 1.1 Conservation Importance of the Batang Toru forest complex ...... 1 1.2 Background to Surveys ...... 4 1.2.1 SOL Site description ...... 4 1.2.2 Geographical scope ...... 5 1.2.3 Aims of the biodiversity monitoring field surveys ...... 5 1.2.4 Target species ...... 6 2. Methodology ...... 7 2.1 Introduction ...... 7 2.2 Camera Trapping ...... 7 2.2.1 Equipment& time frame ...... 7 2.2.2 Locations of camera traps ...... 7 2.2.3 Monthly Camera Trap Checking ...... 7 2.3 Primate and sun bear surveys...... 9 2.3.1 Orangutan Nest Surveys ...... 9 2.3.2 Gibbon/Siamang Fixed Call Count Surveys...... 10 2.3.3 Sun bear sign surveys ...... 11 3. Results ...... 12 3.1 Results -‐ Camera Trapping ...... 12 3.1.1 Time-‐frame and number of independent events ...... 12 3.1.2 Vegetation description Camera of Trap Locations ...... 12 3.1.3 Species encountered on camera traps...... 14 3.1.4 Camera trap performance and condition...... 24 3.2 Results -‐ Line Transect Surveys ...... 25 3.3 Results – Orangutan Nests ...... 30 3.4 Results – Gibbon & Siamang Vocal Surveys ...... 35 4. Discussion ...... 40 4.1 Discussion Biodiversity Surveys and Camera Trapping ...... 40 5. REFERENCES: ...... 42 APPENDIX I APPENDIX II APPENDIX III

List of Figures

Fig. 1. Map of SOL survey area and YEL research station in the WBTFB ...... 2 Fig. 2 Map of overall project site MacDonald included in Mott report, with inset showing the main area of interest...... 5 Fig. 3. Location of camera trap placements...... 13 Fig. 4. Barking deer, male and female, at SOL ...... 15 Fig. 5. Location of Greater mouse deer and ac Barking deer/Red Muntj encounters...... 16 Fig 6. Location of small carnivore encounters...... 17 Fig. 7. Pig-‐tailed macaques interested in the camera ...... 18 Fig. 8. A treeshrew, Tupaia sp...... 18 Fig. 9. Pangolin at SOL ...... 19 Fig. 10. Marbled cat at SOL ...... 19 Fig. 11. Location of Pangolin, Marbled cat and Tiger (sign) encounters...... 20 Fig. 12. Location of Sambar deer, Serow and Wild pig encounters...... 21 Fig. 13. Location of Pig-‐tailed macaques, Agile gibbon, Siamang and monkey Mitred leaf encounters...... 22 Fig. 14. Hunters and dogs were caught on camera traps on 23 events...... 23 Fig. 15. Location line transects and primate listening posts ...... 25 Fig. 16. Map of all sun bear sign encountered during Stage 1...... 27 Fig. 17. Fresh sun bear (VU) sign (here two different clawmarks) was one of the most commonly encountered animal sign in the SOL project area...... 28 Fig. 18. Vertebrate species direct and indirect ing encounter rates dur the June 2014 systematic transect surveys...... 29 Fig. 19. Map of orangutan nests encountered and projected home ranges of male/female orangutans from the -‐ mid point of the locations where nests were encountered...... 31 Fig. 20. Adult male orangutan from the West Batang Toru forest block...... 32 Fig. 21. Relatively fresh (<1 month) orangutan nest encountered during surveys in the SOL area (below) ...... 32 Fig. 22. Two orangutan nests encountered near SOL ibly project area, poss constructed by mother and juvenile infant, or a male rt and female conso (7th of June 2014)...... 33 Fig. 23. Location of the orangutan nests in the tree canopies...... 34 Fig. 24. Gibbon group observed at SOL during the line surveys (June 2014)...... 35 Fig. 25. Box-‐and-‐whiskers plot of agile gibbon call ed times, display by listening post. 1-‐ Listening post 1; 2-‐ listening post 2; 3-‐ listening post 3. Note the low distribution for listening post 2, followed by listening post 1, and listening post 3...... 37 Fig. 26. Box-‐and-‐whiskers plot of siamang call times, stening displayed by li post. -‐ 1 Listening post 1; 2-‐ listening post 2; 3-‐ listening post 3. Note the low distribution for listening post 2, followed by listening post 1, and listening post 3...... 37

Fig. 27. Comparative box-‐and-‐whiskers plot of agile gibbon ll and siamang ca times. – SOCP Sumatran Orangutan Conservation Programme; – SOL Sarulla Operations Limited. The SOCP data is unpublished data from -‐ the SOCP long term monitoring station in the West Batang Forest Block...... 38 Fig. 28. Triangulated vocal points and estimated agile group ranges of gibbons (Hylobates agilis)...... 38 Fig. 29. Triangulated vocal points and estimated siamamg group ranges of (Symphalangus syndactylus)...... 39

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List of Tables

Table 1: Mammal species (non-‐Chiropteran) encountered in the West Batang Toru Forest Block (PanEco/YEL data 2006-‐2014) and their IUCN/Indonesian Protected status...... 3 Table 2: Location, number of camera at that and location, begin end date of rapping camera t at that location, coordinates, altitude and vegetation ion descript of each camera trapping location...... 12 Table 3: Species caught on camera trap at SOL (16 Nov 2013-‐21 June 2014), ranked by number of events...... 14 Table 4: IUCN listing and protected status of species camera trapped at SOL ...... 18 Table 5: Mammal species encountered in the heir SOL area, with t IUCN/Protected status and whether species were directly observed, caught on camera trap (CT) or their sign encountered...... 23 Table 6: Camera trap performance...... 24 Table 7. Vertebrate species encountered (both and directly indirectly) during the June 2014 line transect surveys...... 26 Table 8. Line transect survey summary statistics...... 29 Table 9. Summary statistics for the agile ys. gibbon vocal surve ...... 36 Table 10. Summary statistics for the siamang vocal surveys...... 36

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1. Introduction

1.1 Conservation Importance of the Batang Toru forest complex The East and West Batang Toru Forest Blocks have received significant conservation attention over the last decade, after the 'discovery' of a viable orangutan population in the late 1990s (Wich et al. . 2003) This, and follow-‐up surveys in the East and West Batang Toru Forest Blocks have resulted in the current population -‐ estimate of 400 600 orangutans (Singleton et al. 2004). This area harbours the only viable orangutan population south of Lake Toba, which is now known to be genetically unique relative to other orangutan populations (Nater et al. 2011, 2012), making it the most endangered Sumatran orangutan population. The West Batang Toru Forest Block (WBTFB) consists of medium elevation hill and submontane forest primarily covering extremely rugged terrain (400-‐1300m asl.), and contains orangutans throughout its c. 810 km2 (81.344 ha) of forest. A smaller orangutan population has also been encountered in the East Batang Toru forest block (forest area: 54.940 ha), east of the -‐ Tarutung Sipirok road. The Batang Toru forests are also home to the critically endangered Sumatran tiger. The most recent published Sumatran tiger population, estimated at 300 individuals in the wild, is scattered throughout the island of Sumatra (Ministry of Forestry, 2007), although this number is considered to be an underestimate (Wibisono et al., 2011). Sumatran tigers have been camera trapped in various locations and observed directly on rare asions occ throughout the West and East Batang Toru Forest Blocks over the last decade. In addition, orangutans, tigers, tapirs, serow, pangolins and a variety of other Endangered and Vulnerable mammal species have egularly been caught r on camera traps in an ongoing monitoring programme carried out by PanEco/YEL in the East and West Batang Toru F orest B locks. Extensive biodiversity surveys have been n carried out i the West Batang Toru Forest Block (PT.Newmont Horas Nauli/Hatfindo 2003, PanEco/YEL -‐ 2006 onwards, Conservation International 2007/2008) and the East Batang Toru Forest Block (PanEco/Yayasan Ekosistem Lestari 2007). Since 2006, PanEco/Yayasan Ekosistem Lestari (YEL), who jointly run the Sumatran Orangutan Conservation Project (SOCP) have been operating a flora and fauna monitoring station in the West Batang Toru Forest Block, located some 20 km from the SOL project area (see Fig. 1). The forest area in between the two locations is contiguous primary forest, at elevations around 1000 m asl.

Fig. 1. Map of SOL survey area and YEL research he station in t WBTFB

PanEco/YEL/SOCP have operated a small number of camera traps in the study area near the monitoring station since 2009. In combination with direct , observations a total of 52 mammal species -‐ (non Chiropteran) have been documented in the Table WBTFB so far ( 1).

# Order Latin English Protected_IndonesiaIUCN Red List 1 Carnivora-Felidae Panthera tigris sumatrae Sumatran tiger 1 CE 2 Primata-Pongidae Pongo abelii Sumtatran orangutan 1 CE 3 Perissodactyla_Tapiridae Tapirus indicus Asian Tapir 1 EN 4 Pholidota-Manidae Manis javanica Pangolin 1 EN 5 Primata-Cercopithecidae Presbytis melalophos Mitred leaf monkey EN 6 Primata-Hylobtaidae Hylobates agilis Agile gibbon 1 EN 7 Primata-Hylobtaidae Symphalangus syndactylus Siamang 1 EN 8 Carnivora_Viverridae Arctitis binturong Binturong 1 VU 9 Carnivora-Felidae Pardofelis marmorata Marbled cat 1 VU 10 Carnivora-Ursidae Helarctos malayanus Malayan sun bear 1 VU 11 Artiodactyla_Cervidae Cervus unicolor Sambar deer 1 VU 12 Artiodactyla_Cervidae Capricornis sumatrensis Serow 1 VU 13 Primata-Lorisidae Nycticebus coucang Slow loris 1 VU 14 Carnivora_Mustelidae Aonyx cinerea Oriental small-clawed otter 1 VU 15 Carnivora_Viverridae Hemigalus derbyanus Banded Palm Civet VU 16 Primata-Cercopithecidae Macaca nemistrina Pig tailed macaque VU 17 Rodentia_Muridae Maxomys whiteheadi Whitehead’s spiny rat VU 18 Rodentia_Muridae Niviventer cremoriventer Dark-tailed tree rat VU 19 Carnivora-Felidae Pardofelis teminckii Golden cat 1 NT 20 Rodentia_Sciuridae Callosciurus nigrovittatus Black banded squirrel NT 21 Rodentia_Sciuridae Ratufa affinis Black giant squirrel NT 22 Rodentia_Sciuridae Sundasciurus hippurus Horse-tailed squirrel NT 23 Rodentia_Sciuridae Rhinosciurus*laticaudatus Shrew&faced+ground+squirrel NT 24 Carnivora_Viverridae Prionodon linsang Banded Linsang 1 LC 25 Carnivora-Felidae Prionailurus bengalensis Leopard cat 1 LC 26 Artiodactyla_Cervidae Muntiacus muntjac Common Barking deer 1 LC 27 Dermoptera-Cynocephalidae Cynocephalus variegatus Colugo 1 LC 28 Rodentia_Hystricidae Hystrix brachyura Asian porcupine 1 LC 29 Rodentia_Sciuridae Lariscus insignis Three-striped ground squirrel 1 LC 30 Artiodactyla_Tragulidae Tragulus javanicus Lesser mouse deer 1 LC 31 Artiodactyla_Tragulidae Tragulus napu Greater mouse deer 1 LC 32 Carnivora_Mustelidae Martes flavigula Yellow-throated marten LC 33 Carnivora_Mustelidae Mustela nudipes Malay weasel LC 34 Carnivora_Viverridae Paguma larvata Masked palm civet LC 35 Carnivora_Viverridae Paradoxurus hermaphroditus Common palm civet LC 36 Carnivora_Viverridae Arctogalidia*trivirgata Small&toothed+palm+civet LC 37 Artiodactyla_Suidae Sus scrofa Wild pig LC 38 Insectivora-Erinaceidae Echinosorex gymnura Moonrat LC 39 Rodentia_Hystricidae Trichys fasciculata Long-tailed porcupine LC 40 Rodentia_Muridae Leopoldamys sabanus Long-tailed giant rat LC 41 Rodentia_Muridae Maxomys surifer Red spiny rat LC 42 Rodentia_Muridae Niviventer fulvescens Chestnut rat LC 43 Rodentia_Muridae Rattus exulans Polynesian rat LC 44 Rodentia_Muridae Rattus tanezumi Japan’s house rat LC 45 Rodentia_Muridae Rattus tiomanicus Malaysian field rat LC 46 Rodentia_Muridae Sundamys muelleri Muller’s rat LC 47 Rodentia_Sciuridae Nannosciurus melanotis Black-eared pygmy squirrel LC 48 Rodentia_Sciuridae Sundasciurus tenuis Slender squirrel LC 49 Rodentia_Sciuridae Sundasciurus lowii Low's squirrel LC 50 Rodentia_Rhizomyinae Rhizomys*sumatrensis Sumatran Bamboo Rat LC 51 Scandentia-Tupaiidae Tupaia glis Common treeshrew LC 52 Scandentia-Tupaiidae Tupaia tana Large treeshrew LC Table 1: Mammal species -‐ (non Chiropteran) encountered in the West Batang Toru Forest Block (PanEco/YEL data 2006-‐2014) and their IUCN/Indonesian Protected status.

1.2 Background to Surveys In September 2013, PanEco/YEL were approached by Mott MacDonald, who had been commissioned by Sarulla Operations Ltd (SOL) to coordinate biodiversity monitoring field surveys at their Sarulla geothermal , field to assist with these . surveys An initial reconnaissance (recce) was carried out in November 2013 (see d report include as Appendix III), followed by more intensive line transect and primate call monitoring surveys in June 2014. Between November 2013 ne and Ju 2014 a camera trapping programme was run. The following description of the site, geographical location, the aims of the monitoring surveys, and list of species of interest are taken from the March 2014 Mott MacDonald proposal on the Biodiversity Monitoring Metholodogy (in italics).

1.2.1 SOL Site description The overall Sarulla Geothermal Project comprises two geothermal fields (Namora I Langit or "NIL" field, and Silangkitang SIL or " " field), each consisting of a power station (two at NIL), production and -‐ re injection wells, connecting pipeline, and a transmission line to the Perusahaan Listrik Negara (PLN) power -‐ sub station. The Project is located between the East and West Batang Toru Forest Blocks in the Sarulla valley (Figs. 1 and 2). The majority (approximately 90%) of the infrastructure will be located within existing areas of Modified habitats (as defined under IFC Performance Standard sented 6) and are repre by four vegetation communities: yard vegetation, field vegetation, rubber antation pl and mixed plantation vegetation. These habitats have been assessed as not being of significant conservation importance and the impact upon them is considered to be negligible (Biodiversity Impact Assessment, ERM, 2013). These areas will not be surveyed as part of this biodiversity monitoring program.

Approximately 10% of the Project will hin be located wit an area identified as Natural/ Critical Natural Habitat (IFC PS6). This area is situated around the infrastructure of NIL1 and WJP1. The habitats within the Project footprint comprise secondary lower montane (dipterocarp) forest, natural scrub (padang vegetation), heath forest, non-‐natural scrub and mixed forest (Habitat Condition Assessment, Mott MacDonald, 2013). Collectively this area covers approximately 8ha.The biodiversity monitoring program will target the habitats within these areas. Approximately 92ha of the Project is located within the Western Batang Toru Forest Block (WBTFB). This area is situated around the infrastructure of the NIL Geothermal Field (see Error! Reference source not ). found. The habitats within and adjacent to the Project comprise secondary (dipterocarp) forest, natural scrub (padang vegetation), scrub forest (heath forest), non-‐natural scrub, and mixed forest (Mott MacDonald, 2013). The biodiversity monitoring program will target these habitats a. within this are

Fig. 2 Map of overall project site included in Mott MacDonald report, with inset showing the main area of interest

1.2.2 Geographical scope The geographical scope of the surveys comprised three zones as follows: Zone 1: Habitats within the footprint ucture of the infrastr identified as Natural/Critical Natural Habitat (NIL1 and WJP1). Zone 2: Habitats within 500m of the rastructure footprint of the inf identified as Natural/Critical Natural Habitat. Zone 3: Habitats over 500m from the rastructure footprint of the inf identified as Natural/Critical Natural Habitat. These comprise the wider landscape within the Batang Toru Forest. The biodiversity monitoring field surveys targeted the habitats located within Zones 1 & 2 (collectively hereafter the ‘Project Area’), as well Zone 3 as these areas are considered part of the ranges of various species occurring in the 'Project Area'.

1.2.3 Aims of the biodiversity monitoring field surveys The aims of the biodiversity monitoring field surveys are as follows:

To provide further baseline data on the likely presence and habitat usage of species of conservation importance (‘Target Species’), which are known or have the potential to occur in the Project Area. This includes: − Creating habitat and species distribution maps. − Interpreting data collected from the field surveys in the context of the Project and the wider conservation objectives of the Batang Toru Forest. To monitor the likely effects of the Project on nform Target Species and to i changes to the Environmental Management Plan as well as requirements within the Biodiversity Action Plan and Biodiversity -‐ Off set Management Plan.

1.2.4 Target species Seven species were initially identified as occurring, or having the potential to occur, within the Project Area and were said to be listed by the IUCN Red List as Critically Endangered or Endangered. This initial list of target was species as follows:

1. Sumatran orang-‐utan (Pongo abelii) [Critically Endangered, IUCN Red ; List] 2. Sumatran tiger (Panthera tigris sumatrae) [Critically Endangered, IUCN Red List]; 3. Asian tapir (Tapirus indicus) [Endangered, IUCN Red List]; 4. Malayan pangolin (Manis javanica) [Endangered, IUCN Red List]; 5. Mitred leaf-‐monkey (Presbytis melalophos) [Endangered, IUCN Red List]; 6. Siamang (Symphalangus syndactylus) [Endangered, IUCN Red List]; 7. Agile gibbon (Hylobates agilis) [Endangered, IUCN Red List].

A list of other species identified within the Project area was put forward, all recognized as species of conservation importance, others as important prey species for Sumatran . tiger These were to be considered secondary species, to be recorded during the biodiversity monitoring, but not be ct subje to species-‐specific surveys:

1. Marbled cat (Pardofelis marmorata) [Vulnerable, IUCN Red ; List] 2. Sumatran serow (Capricornis sumatraensis) [Vulnerable, IUCN Red ; List] 3. Sambar deer (Cervus unicolor) [Vulnerable, IUCN Red ; List] 4. Malayan sun bear (Helarctos malayanus) [Vulnerable, IUCN Red ; List] 5. Binturong (Arctictis binturong) [Vulnerable, IUCN Red ; List] 6. Slow loris (Nycticebus coucang) [Vulnerable, IUCN Red . List] 7. Wild ar bo (Sus scrofa). A number of other species listed as Vulnerable -‐ under the IUCN red list are also known to occur in Batang the Toru forest(see Table 1 ).

2. Methodology

2.1 Introduction The methodologies used in the initial ecce) reconnaissance (r survey conducted in November 2013, are described in the report on the findings of the survey (included here as Appendix III). The methodologies described below are for the camera trapping, and primate and sun bear surveys conducted during the surveys in June May/ 2014.

2.2 Camera Trapping Camera traps are the preferred survey technique e for some of the mor cryptic fauna (e.g., tiger, marbled cat, pangolins, tapirs). PanEco/YEL have been operating camera traps in the Batang Toru forest complex starting in 2008. Camera traps were utilized for the biodiversity surveys in the SOL project area to determine the presence, distribution, and relative abundance of various cryptic faunal species. Techniques followed here are similar to those described by Ancrenaz et 12). al. (20

2.2.1 Equipment& time frame A total of 6 Bushnell X-‐8 Trail Cam [model 119327] camera traps were provided by Mott McDonald in November These 2013. camera's make use of a 'passive' ing trapping system, be triggered when an object with a different temperature than the ambient temperature moves within the camera’s detection zone. s These camera are in theory less prone to false captures, but are more prone to “heat blindness” when high ambient temperatures approach mammalian body temperatures. Camera trapping commenced on 18th of November 2013 and continued till 21st of June 2014.

2.2.2 Locations of camera traps This Stage 1 camera trapping survey aimed to cover a combination of habitat types and locations within the forest areas of NIL1 and WJP1. A survey grid was created, made up of 500 m x 500 m grid cells. The six camera traps were deployed within ’, the ‘Project Area placed at least 100 meters from one another.

2.2.3 Monthly Camera Trap Checking Following placement, the -‐ camera traps were run between 2-‐3 months at a single location, depending on previous . results Camera-‐traps were checked approximately once a month, and the following actions were taken:

¡ Check and replace batteries; ¡ Change SD card; ¡ Ensure that the camera is still functioning ere and that th is nothing obstructing the camera’s lens. After each camera trap session the following data was be recorded for each camera trap night:

¡ Species aptured c ; ¡ The number apture of c events per species; ¡ The number of individuals per event.

Each period that one camera trap was left in the field for approximately 1 month was labelled as a separate a "session". A camera trap could be left for another session at the same location if several or interesting animals were photographed during the previous session.

Locations for placement of the camera traps were chosen to maximize results, thus traps were placed in locations with tracks, scats or animal trails. The camera trap was generally placed 50cm above the ground to try to detect ze, animals of various si although this was partly dependent on slopes the in different locations. Camera traps were set to take hree t pictures each time the sensor was triggered to maximize chances of identification. Identification of species was assisted with the help of two mammal identification books: A field guide to the Mammals of Borneo by J. Payne, C. Francis, K. Phillips 2007) ( and A field guide to the -‐ Mammals of South East Asia by C. Francis (2008). Some pictures were sent to specialists to assist with identification . We efined d a species recording as an ‘event’ when a photograph (or series of photographs) of an individual species (counting number of individuals of that species) was recorded by the same camera at one location, including all other pictures of the same species taken within a time period of 30 minutes at the same camera placement (Linkie and Riboud 2011). Photographs that were recorded within 30 min of a previous photograph of the same species, and at the same camera placement, were not recorded as an event, because they were not considered to be independent species events.

2.3 Primate and sun bear surveys Primate and sun bear surveys were to be undertaken during two intensive monitoring periods: once -‐ pre construction in May/June 2014 and once following construction in April/May 2017. The following materials were and methods to used: be

2.3.1 Orangutan Nest Surveys Using orangutan nest surveys, relative sities orangutan den were to be calculated for the Project area following a ly previous published protocol (e.g. van Schaik et al., 1995, Buij et al., 2002, Buij et al., 2003, Wich et al., 2004). This methodology relies on the fact that orangutans construct nests daily, which are used at night and also sometimes during the day for resting (van Schaik et al., 1995, ng Singleton, 2000). Usi nest counts instead of live encounters with orangutans is preferred here due to the low density of orangutans, which makes density estimates based on live ry encounters a ve time consuming exercise. Nest unts co were to be conducted along 20 randomly placed transects in the Project area, following methods of Marshall et al. (2008) and Buckland et al. (2010), with each transect being 500 m in length, with a minimum of 200 meters between transects. All line transects should be only large enough for observers to walk without disruption. It is recommended that the surveyors wait a week after the line transects are cut before they start the line transect surveys. This allows the animal population that may have been disturbed during the making of the line , transects to come back into the area. During nest counts, two experienced observers slowly walked on transects and record the perpendicular distance of all identified nests. Perpendicular es distanc are measured with a hip chain. Each transect was walked twice, once in each direction. Orangutan density was estimated from nest counts using the following formula:

d = N/(L * 2 * w * p * r t) in which :

d = orangutan density (individuals/km2), N = number of nests observed along the transect, L = length of the transect covered (km), w = estimated width of the strip of habitat y actually visuall covered (km), p = proportion of nest builders in , the population r = rate at which nests are produced (n/day/individual), and t = time during which a nest remains visible (in days). Estimating strip width (w): Using the measured perpendicular distance rom of nests f the transect line, (w) was estimated using the computer programme ''Distance 6.0'' (Thomas et al., 2001). Parameters (p) and (r): -‐ In two long term studies of Sumatran orangutans, roughly 10% of the population was comprised -‐ of non nest building infants, and as such, (p) was set at 0.9. Conversely, in the same two Sumatran orangutan populations, the number of nests built per day (r) was found to be approximately 1.7 995). (van Schaik et al., 1

Nest decay rate (t): A study by Buij et al. (2003) found that lationship there is a negative re between (t) (i.e., the number of days a fter nest remains visible a it has been constructed) and topsoil pH. The rationale behind this at relationship is th nest decay is thought to be partly dependent on the hardness of the wood , of the nest trees and the hardness of wood is thought to be higher with a decrease in topsoil pH (Buij et al. 2003). PH values have been measured at various locations near the YEL/SOCP research station and detailed data on nest decay rates in the Batang Toru een forest have b calculated from previous YEL studies ( unpublished data).

2.3.2 Gibbon/Siamang Fixed Call Count Surveys While gibbons and siamangs can also be surveyed via line transects, the abundance estimates that are obtained for direct contact dered surveys are consi a minimum estimate, as these species are extremely cryptic. However, both these species have distinctive calls and thus the density of gibbon and siamang groups was to be calculated using the fixed call count methodology established by Brockelman & Ali (1987). In particular, a series of three listening stations (all consisting of a set of three listening posts each), were each to be monitored for five consecutive days. , Each survey day between 05:00 – 12:00, surveyors from each listening post recorded the time of a group’s call, the species (i.e., gibbon or siamang), the compass bearing, and the estimated distance. Via triangulation, group calls were then marked on a map in GIS, and the total number of gibbon and siamang groups heard was estimated for each listening location. In order to control for call point location estimation errors, vocalization points were restricted to within a 500 meter radius from any given listening post. Additionally, a given vocalization had to have been heard from at ening least two list posts. The effective listening area E ( ) for both gibbons and siamangs was then calculated by drawing a polygon around all useable vocalization points. Group density estimates D ( ) will be calculated using the equation: D = n/[p(m) x E] (Brockelman & Ali, 1987) where: n = the number of groups heard, p(m) = the estimated proportion of groups expected to sing at a survey location during a sampling period m of days, E = Effective listening area. Also following Brockelman & Ali (1987), p(m) was determined using the equation: p(m)=1-‐[1-‐p(1)]m where: p(1) = the average probability of singing for any given day, m = the number of survey days.

2.3.3 Sun bear sign surveys A relatively high density of sun bear sign was ect encountered in the proj area during the preliminary survey in November 2013. As sun bears are protected under Indonesian law and considered Vulnerable under the IUCN red book (Fredriksson et al. 2008), it was proposed to carry out sun bear sign transects as a relative tool to monitor the abundance of sun bear sign (i.e. claw marks, termite diggings) expressed as number of sign/ha (fresh/old; type of sign) in the project area. Sign were transects carried out prior to road construction activities to WJP1 (May/June 2014) and once more after construction activities finalized have been . Bear signs were recorded along twenty 10m wide x 500m long (0.5 ha) strip-‐transects. These sign surveys will be carried out along the same transects as made for the orangutan nest surveys. Each transect was surveyed by a team of three people, with one person moving slowly along the midline whilst recording ances data and dist with a Walktax Distance Measurer (Forestry Suppliers , Inc. USA), and two people zigzagging on either side of the midline in search of sign throughout the 5-‐m strip of forest on either side of the midline. All sun bear signs encountered within the strip-‐transect were investigated in detail and recorded after ensus cons was achieved among the researchers. Type of sign was recorded, estimated age of sign, as was the forest category in which sign was encountered (i.e. ridge, swamp, slope). All tree stems >5 cm DBH were investigated for claw marks, and the forest floor was searched for dug up or broken termite ions, nests, soil excavat or logs ripped by sun bears. On average 2.5 hours were used to record signs along one -‐ 500 m strip transect. Within strip-‐transects, live aboveground termite nests Ficus and figs ( spp., both trees and hemi-‐epiphytes) were also recorded during surveys as termites and figs make up a large proportion of the sun bear diet (Wong et al. . 2002, Fredriksson et al 2006).

3. Results

3.1 Results Camera -‐ Trapping

3.1.1 Time-‐frame and number of independent events Between 16th November 2013 and 21st of June 2014, a total of 984 trap nights were carried out. During these, a total of 92,689 pictures were taken. Of . these, 2 978 pictures were of mammal/bird species. In total 527 independent re events we recorded.

3.1.2 Vegetation description of Camera Trap Locations A total of 11 different locations were used amera for placement of the c traps. Table 2 describes the beginning and end date of placement at that location, altitude, and vegetation description of each location. Fig. 3 shows the locations of camera trap placement in relation to NIL 1 and WJP.

Loc No CT Start date End date Trapnights LAT_2 LONG_2 Alt Location description

Primary forest, 'arang' type vegetation, flat ridge, dry area, near human trail L1 CT1 16-Nov-13 21-Nov-13 5 1.8754 99.0205 930 used for access and bird catching Primary forest, 'arang' type vegetation/mossy forest, flat area, near standing L2 CT2 16-Nov-13 21-Nov-13 5 1.8747 99.0228 943 water L3 CT3 17-Nov-13 22-Nov-13 5 1.8812 99.0112 1065 Secondary forest, high canopy, understory dominated by ferns L4 CT4 17-Nov-13 22-Nov-13 5 1.8814 99.0130 1078 Secondary forest near a hill top, human disturbance (illegal logging) nearby Secondary forest, high canopy, understory dominated by ferns, standing water 942 L5 CT5 19-Nov-13 21-Jun-14 214 1.8780 99.0274 pool L6 CT6 18-Nov-13 21-Jun-14 116 1.8818 99.0262 918 Old rubber/benzoin garden, thick undergrowth L7 CT1 21-Nov-13 2-Apr-14 118 1.8742 99.0206 916 Secondary forest, high canopy, understory open Primary forest, 'arang' type vegetation, flat ridge, dry area, near human trail L8 CT2 21-Nov-13 18-Feb-14 89 1.8746 99.0242 826 used for access and bird catching L9 CT4 22-Nov-13 21-Jun-14 211 1.8796 99.0298 945 Secondary forest, flat ridge, high canopy and open understory L10 CT3 22-Nov-13 21-Jun-14 93 1.8802 99.0293 931 Secondary forest, high canopy, hilly area Secondary forest, high canopy, understory dominated by ferns, area with tree L11 CT2 18-Feb-14 21-Jun-14 123 1.8739 99.0254 961 fall Table 2: Location, number of camera at that location, begin and end date of camera trapping at that location, coordinates, altitude and vegetation description of each camera trapping location.

Fig. 3. Location of camera trap placements. Numbers (L1-‐L11)refer to Table 2.

3.1.3 Species encountered on camera traps A total of 16 mammal species were photographed and identified to species level (table 3). Treeshrews Tupaiidae) ( were grouped at genus level, as identification to species level is difficult without physical measurements. From visual identification, at least 2 species of treeshrew are thought to have been caught on Tupaia the camera traps ( tana, T. minor/T. glis). All rats/mice that were photographed were grouped under their family name Muridae and no attempt was made to identify these, as physical measurements are needed to identify most species. A small number of pictures were obtained of unidentified ds bir 7), (n= bats n= ( 2), a lizard/skink (n=1), and a n= snake ( 1). Photographs of another 15 events were obtained where species identification was not deemed possible. The three most common species photographed made up 69% of all events. These were the Red Muntjac/Barking deer Muntiacus muntjac (n=154 events, 29%: see Figs. 4 and , 5) followed by Pig-‐tailed macaques, Macaca nemestrina (n=142 events, 27%: see Fig. 7), and Treeshrews, Tupaia spp. (n=69, 13%; see Fig. 8). Species Scientific(name No)of)events % IUCN)status Protected Red$Muntjac/Barking$deer Muntiacus)muntjac 154 29.2 LC X Pigdog Canis)familiaris 4 0.8 Emerald$dove Chalcophaps)indica 4 0.8 Masked$palm$civet Paguma)larvata 3 0.6 LC Pangolin Manis)javanica 3 0.6 EN X Shrew

TOTAL)EVENTS 527 Table 3: Species caught on camera at trap SOL (16 Nov 2013-‐21 June , 2014) ranked by number of events.

See also Appendix I for examples of camera es trap pictures of speci not included in the main text of this report.

Fig. 4. Barking deer, male and female, at SOL

A total of 24 independent events were also photographed of the greater mouse deer (Tragulus napu), a species protected under Indonesian law. Locations of barking deer and mouse deer camera trap pictures or encounters seen can be in Fig. 5.

Fig. 5. Location of Greater mouse deer and Barking /Red deer Muntjac encounters.

Several other species of the Carnivora order were either observed or caught on camera traps. These included the Banded Prionodon Linsang ( linsang), the Masked palm civet Paguma ( larvata), the Common palm civet Paradoxurus ( hermaphroditus), and the Small-‐toothed palm civet Arctogalidia ( trivirgata) from the Viverridae, and from the Mustelidae, the Yellow-‐throated marten Martes ( flavigula) and the rarely observed Malay weasel Mustela ( nudipes). F ig. 6 provides a map of these smaller carnivore encounter locations.

Fig 6. Location of small carnivore encounters.

Fig. 7. Pig -‐tailed macaques interested in the camera

Fig. 8. A treeshrew, Tupaia sp.

A total of 33.8% of events were photographs of species listed as Endangered or Vulnerable under the IUCN Red List. Species protected under Indonesian law made up 43.5% of all events T ( able 4 ). Species Scientific(name IUCN+status Protected No+of+events % Pangolin Manis&javanica EN X 3 0.6 Pig/tailed3macaque Macaca&nemestrina VU 142 26.9 Sambar3deer Rusa&unicolor VU X 31 5.9 Marbled3cat Pardofelis&marmorata VU X 2 0.4 Red3Muntjac/Barking3deer Muntiacus&muntjac LC X 154 29.2 Greater3mouse/deer Tragulus&napu LC X 24 4.6 Three/striped3ground3squirrel Lariscus&insignis LC X 9 1.7 Banded3Linsang Prionodon&linsang LC X 6 1.1 Table 4: IUCN listing and protected status of species camera trapped at SOL

Pangolins, Manis javanica (EN) were photographed on 3 occasion at different locations (Figs. 9 and ) 11 . The marbled cat, Pardofelis marmorata (VU), was twice caught on camera traps at different locations (Figs. 10 and ) 11 . A tiger scat containing pangolin remains found during the recce surveys in November 2013 is also plotted on Fig. 11. Sambar deer, Rusa unicolor (VU), were photographed on 31 independent events (Fig. 12). Pig-‐tailed macaques (VU) were photographed on 142 independent ts even (Figs. 7 and ). 13

Fig. 9. Pangolin at SOL

Fig. 10. Marbled cat at SOL

Fig. 11. Location of Pangolin, Marbled cat (sign) and Tiger encounters.

Fig. 12. Location of Sambar deer, Serow and Wild pig encounters.

Fig. 13. Location of -‐ Pig tailed macaques, Agile gibbon, Siamang and Mitred leaf monkey encounters.

Fig. 14. Hunters and dogs were caught on camera traps on 23 events (4.4% of total events).

No pictures were obtained of Sumatran rs, tiger, sun bea serow, or tapir, despite the fact that indirect evidence of the first three of these species was found during the recce surveys carried out between 16-‐22 November 2013 (PanEo/YEL, : 2013 see Appendix III to this report) as well as the biodiversity surveys in June 2014. A total of 27 mammal species were encountered in the SOL area between November 2013-‐ June 2014 during the combined recce, camera trapping and biodiversity surveys (see table 5).

Order English Latin IUCN Protected CT Obs Sign Carnivora-Felidae Sumatran tiger Panthera tigris sumatrae CE 1 Scat Primata-Pongidae Sumtatran orangutan Pongo abelii CE 1 Nests Pholidota-Manidae Pangolin Manis javanica EN 1 V Scales in Tiger scat Primata-Cercopithecidae Mitred leaf monkey Presbytis melalophos EN V Primata-Hylobtaidae Siamang Symphalangus syndactylus EN 1 V Primata-Hylobtaidae Agile gibbon Hylobates agilis EN 1 V Carnivora-Felidae Marbled cat Pardofelis marmorata VU 1 V Carnivora-Ursidae Malayan sun bear Helarctos malayanus VU 1 Fresh feeding sign Cervidae Sambar deer Cervus unicolor VU 1 V Scat and footprints Cervidae Serow Capricornis sumatrensis VU 1 V Scat and footprints Primata-Cercopithecidae Pig-tailed macaque Macaca nemistrina VU V V Carnivora_Viverridae Banded Linsang Prionodon linsang LC 1 V Cervidae Common Barking deer Muntiacus muntjac LC 1 V Scat and footprints Tragulidae Lesser mouse deer Tragulus javanicus LC 1 V Tragulidae Greater mouse deer Tragulus napu LC 1 V Rodentia_Sciuridae Three-striped ground squirrel Lariscus insignis LC 1 V Rodentia_Sciuridae Shrew-faced ground squirrel Rhinosciurus laticaudatus LC 1 V Carnivora_Mustelidae Yellow-throated marten Martes flavigula LC V Carnivora_Mustelidae Malay weasel Mustela nudipes LC V Carnivora_Viverridae Masked palm civet Paguma larvata LC V Carnivora_Viverridae Common palm civet Paradoxurus hermaphroditus LC V Carnivora_Viverridae Small%toothed+palm+civet Arctogalidia+trivirgata LC V Suidae Wild pig Sus scrofa LC V Scat and footprints Rodentia_Sciuridae Low's squirrel Sundasciurus lowii LC V Scandentia-Tupaiidae Common treeshrew Tupaia glis LC V Scandentia-Tupaiidae Large treeshrew Tupaia tana LC V Rodentia_Sciuridae Black banded squirrel Callosciurus nigrovittatus NT V Table 5: Mammal species encountered in the SOL area, with their IUCN/Protected whether status and species were directly observed, caught on camera trap (CT) or their sign encountered.

3.1.4 Camera trap performance and condition Out of the 6 camera traps provided, only 2 camera's performed well throughout the 7 month period in the field. The rest (4 units) either had camera/sensor errors commencing not long after initial deployment or after -‐ 2 3 months in the field. One of these was stolen (between 2 April-‐28 May), with the python lock cut through with a machete (Table 6).

# 1st$placement Comments Camera'error'commenced'2nd'of'December,'camera'traking'pictures'every'2'minutes'but' CT 1 16-Nov-13 still'some'animal'pictures'taken;'stolen$between$2$april328$May Camera'error'commenced'2nd'of'June,'camera'traking'pictures'every'2'minutes'but'still' CT 2 16-Nov-13 some'animal'pictures'taken;' CT 3 17-Nov-13 OK Camera'error'commenced'30th'of'December,'camera'traking'pictures'every'2'minutes'but' CT 4 17-Nov-13 still'some'animal'pictures'taken;' CT 5 19-Nov-13 OK Camera'error'commenced'23rd'of'December,'camera'traking'pictures'every'2'minutes'but' CT 6 18-Nov-13 still'some'animal'pictures'taken;' Table 6: Camera trap performance. The cameras that performed with s error still took pictures, but on an almost continuous basis (every 2 minutes). This led to a large amount of pictures (n=92.689) that still needed to be checked, as sometimes randomly pictures had been interesting taken of species.

Due to the small number of camera traps, the relatively high failure rate of s the camera operating under the intense tropical conditions (humidity, rain), and the theft of one camera trap, results from Stage 1 camera trapping effort are not considered optimal for statistical analysis, but still yielded some very interesting photographic evidence of fauna in the area.

3.2 Results Line -‐ Transect Surveys

A total of 22 transects (each 500 m in ically length) were systemat walked in each direction, for a total survey effort of 22 km. Four primary habitat types were surveyed while on transect, including imary 1) pr forest, 2) secondary forest, 3) Arang forest, and 4) Kemenyan gardens Fig ( . 15). For descriptions A of rang forest and Kemenyan gardens, see Appendix III.

Fig. 15. Location line transects and primate listening posts

During the transect walks, efforts were made to collect data on ct all vertebrate dire contacts and indirect signs (e.g., feces, feeding remains, footprints, scratch marks, nests, and vocalizations). From the 22 km walked, there were a total of 54 direct and indirect vertebrate signs recorded 7 (Table ).

Mitred Transect Pig-‐tailed Agile Sambar Pheasant Wild Boar Muntjac Hornbill Siamang Leaf Sun Bear Total (n) # Macaque Gibbon Deer Monkey T1 0 T2 0 T3 1 1 T4 2 2 T5 1 1 T6 1 2 3 3 9 T7 1 1 2 4 T9 2 1 6 9 T10 2 2 T11 1 1 2 T12 1 1 1 3 T13 1 1 T14 1 1 T15 0 T16 1 2 3 T17 2 2 T18 1 3 1 1 6 T21 1 1 2 T22 1 1 T23 1 1 T24 2 2 T25 1 1 Total (n) 1 2 1 1 7 1 15 1 1 23 53 Table 7 . Vertebrate species encountered (both directly irectly) and ind during the June 2014 line transect surveys.

The most frequently contacted mammal, either directly and/or indirectly, was the sun bear, which made up a total of 43.4% of all sign contacts (Table 8; Figs. 16 and 18). Of the 23 indirect sun bear signs found while during the transect surveys, 87% of all sings were in the form of claw marks (Fig. 17) and the remaining 17% were feeding sign on stingless bees (ripped/chewed holes in trees where the bees made their . nest in a cavity) A total of 70% of all sun bear signs were categorized as >1 year old, with the remaining 30% being characterized as <1 year old. Overall un s bear sign densities encountered along the fixed-‐ width transects w as 2.2 sign/ha.

Fig. 16. Map of all sun bear sign encountered during Stage 1.

Fig. 17. Fresh sun bear (VU) sign (here two different clawmarks) was one of the most commonly encountered animal sign in the SOL project area.

Bear signs were found throughout each block of transects and were found as close as 300 m from NIL1 and 200 m from WJP1. The majority of bear signs were found in arang forest (33.3%), followed by primary forest (29.2%), mixed secondary/kemenyan forest (20.8%), secondary forest (12.5%), and mixed arang/kemenyan forest (4.2%).

Transects (n) 22 -‐ -‐ -‐

Transect Length (km) 0.5 -‐ -‐ -‐

Total effort (km) = 2n * km 22 -‐ -‐ -‐ Species n % Total n/km Sign/Obs Pheasant 1 1.9 0.05 Obs Pig -‐tailed Macaque 1 1.9 0.05 Obs Agile Gibbon 1 1.9 0.05 Obs

Hornbill 1 1.9 0.05 Obs

Siamang 1 1.9 0.05 Obs

Mitred Leaf Monkey 1 1.9 0.05 Obs Wild Boar 2 3.8 0.09 Sign Muntjac 7 13.2 0.32 Sign Sambar Deer 15 28.3 0.68 Sign Sun Bear 23 43.4 1.05 Sign

Total 53 100.0 2.41 -‐

Table 8 . Line transect survey summary statistics.

Fig. 18. Vertebrate species direct and indirect es encounter rat during the June 2014 systematic transect surveys. See Tables 7 and 8 above for the summary figures.

After the sun bear, the next most frequently contacted vertebrates along line transects were the sambar deer (28.3% of all contacts), muntjac (13.2% of all contacts), and wild boar (3.8% of all contacts) Table ( 8; Figs. 5, 12 and 18). As with the sun bear signs, the aforementioned vertebrates were found throughout the transect blocks, with the signs found as close as 400 m from NIL1 and 275 m from WJP1. Six additional vertebrate species were directly encountered along the line transects, each a single time (1.9% of all contacts for each species), while on transect (Table 8). These species include the siamang, agile gibbon, mitred leaf monkey, pig-‐tailed macaque, Rhinoceros hornbill, and unidentified species of pheasant. Among the three IUCN Endangered primate species, the siamang contact point was roughly 3 km from both NIL1 and WJP 1, whereas the agile gibbon contact point was roughly 2 km from NIL 1 and 2.5 km from WJP1, and the mitred leaf monkey contact point 0 was <50 m from WJP1 and 1.8 km from NIL1. Due to the small number of contacts, for each of the species contacted, it is not possible to accurately create density estimates. Nevertheless, the most recent survey effort (i.e., June 2014) can again (see results om fr the November 2013 survey) confirm the presence of at least five primate species within the SOL Project area.

3.3 Results – Orangutan Nests While moving between the survey line tal transects, a to of 5 recent orangutan nests were encountered near the SOL Project area (Figure 19 ). Two nests were found in association with one another, possibly indicating two individuals (e.g., mother and infant or a female and male party). The closest orangutan nest to NIL1 was 2 km away, whereas the closest nest to WJP1 was .5 2 km away, with the mean orangutan nest coordinate being 2.1 km away from NIL1 and 2.5 km away from WJP1. Figs. 21 to 23 show photographs of the nests encountered.

Using data from -‐ a long term orangutan monitoring station, Suaq Balimbing in South Aceh, it has been estimated that female orangutans have 50 a home range of >8 ha, while males can have home ranges >2500 Singleton ha ( & van Schaik 2001). Using the mean nest coordinate as a centre point, a circular buffer zone of 850 ha and 500 a circular buffer zone 2 ha were drawn, indicating the potential home ranges of a female and male Sumatran orangutan, respectively (see Figure 19). With these two buffer zones plotted, a female orangutan home range could potentially be within 500 m of NIL1 and 1 km from WJP1, whereas a male orangutan home range would directly overlap with both NIL1 and WJP1. While these are just estimates, it should be noted that Sumatran orangutans from the long-‐term SOCP monitoring station in the West Batang ock Toru Forest Bl are known to travel more than any other previously studied Sumatran orangutan population ). (Wich et al. 2014 As such, the ranging figures presented here are likely to be an underestimate of the home range requirements for both male and female orangutans ng in the Bata Toru Forest Complex.

Fig. 19. Map of orangutan nests encountered and e projected hom ranges ale/female of m orangutans from the mid-‐point of the locations where nests were encountered .

Fig. 20. Adult male orangutan from the West Batang Toru forest block (photograph taken near PanEco/YEL research station, March 2014). t: Photo credi Tim Laman (National Geographic) Fig. 21. Relatively fresh (<1 month) orangutan nest encountered during surveys in the SOL area (below)

Fig. 22. Two orangutan nests encountered near SOL project area, possibly constructed by mother and juvenile infant, or a male and female consort (7th of June 2014).

Fig. 23. Location of the orangutan nests in . the tree canopies