Environmental and Social Monitoring Report

Safeguard and Social Monitoring Report Appendix H – Biodiversity Monitoring 2017 (Monitoring period: July – December 2017) September 2018

INO: Sarulla Geothermal Power Prepared by Sarulla Operations Limited for the Asian Development Bank. This safeguard and social monitoring report 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. 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.

Biodiversity Monitoring 2017

SOL Geothermal Project Area, North Tapanuli, North Sumatra

Camera trapping and Primate Surveys

Apictureofafemalesambardeer(Rusaunicolor)withoffspring,aspeciesprotectedunderIndonesianlawbutstillheavilyhuntedthroughoutSumatra,caughtoncameratrapatSOLin2017.

12th of November 2017 [with revisions 10th Feb 2018] by

PanEco/Yayasan Ekosistem Lestari

requested by

Sarulla Operations Ltd.

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ExecutiveSummary

Biodiversity monitoring is an integral part of the Biodiversity Action Plan (BAP) that wasdevelopedaspartofalarge-scalegeothermaldevelopmentprojectinNorthTapanuli,NorthSumatra,Indonesia.BaselinesurveyswerecarriedoutbetweenNovember2013-June2014by Yayasan Ekosistem Lestari [camera trapping, primate and wildlife surveys, reptile andamphibiansurveys]andateamofexpertslookingatvegetationandbirddiversity.In2016,further camera trapping andprimate surveyswere carriedout as part of annualmammalsurveysinthebiodiverseforestsurroundingtheSarullaOperationsLimited(SOL)project,allpartoftheBatangToruEcosystem.

Thisreportdiscussestheresultsofrepeatbiodiversitysurveysfocusingoncameratrapping[21February-12August2017]andspecificprimatesurveys[16July-12August2017] intheforest area where SOL is developing a large-scale geothermal project in/adjacent to theprotected Batang Toru Ecosystem. These repeat biodiversity surveys are intended as amonitoringtooltoinvestigatetemporalchangesinwildlifepopulationsinrelationtohumandisturbanceintheSOLprojectarea.

TheaimistobalanceSOLgeothermalactivitieswithminimalimpactonwildlifepopulationsandtoproviderecommendationswhatisneededtomaintainhealthywildlifepopulationsintheBatangToruEcosystemsurroundingtheSOLgeothermalarea.

Thebiodiversitydatacompiledin2017,throughcameratrappingandprimatesurveys,havebeen compared with baseline data that was collected in the SOL project area betweenNovember2013-June2014,anddatacollectedin2016.SincethefirstsurveyslandclearingactivitiesandroadconstructionthroughtheforesttotheWJPareahavetakenplace.Theseactivitieswillhaveaffectedresidentwildlifecommunitiesandarborealmovementhasbeenhamperedintheareabisectedbyroads.Reforestationwillbeneeded,startinginkeyareas,torestoreconnectivity.

The orangutans residing in the Batang Toru Ecosystemhave recently been described as aseparategreatapespecies,calledPongotapanuliensis,theTapanuliorangutan.Asonly800individuals of this species are left in the Batang Toru Ecosystem, they are now themostEndangeredGreatApeintheworld.

As stated in theSOLBiodiversityActionPlanandBiodiversityOff-setManagementPlan(2015)“IftheBatangToruOrang-Utanwillofficiallygainthestatusofadistinctspecies,theCHA [CriticalHabitatAssessment]might be re-evaluated.” (p. 34).We recommendthat this re-evaluation of Critical Habitat be carried out, as SOL staff reported seeingorangutansintheNIL/WJPareasomeyearsago,andprimatesurveyscarriedoutin2014encountered several orangutan nests.We recommend that other biodiversity surveysshould also be repeated in order to continuemonitoring of bird diversity and relativeabundance,aswellasreptile/amphibiansurveysinviewofthisgroupbeingimportantasindicatorsofhealthyecosystems.

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Keyfindings

¡ A minimum of 30 mammal species were encountered during the biodiversity surveysduring in2017;ofthese26specieswererecordedfromcameratrap. Inaddition6birdspecies were identified from camera trap pictures and hornbills were heard flyingoverhead during the primate surveys. For comparison, in 2016 overall 17 mammalspecieswererecorded,whereas27speciesofmammalswererecordedin2014.

¡ Of these,10mammalspecies is listedunder the IUCNRedListasCriticallyEndangered[1], Endangered [3] or Vulnerable [6], with 14 mammal species protected underIndonesianlaw;

¡ Twoindependentpangolinevents(Manisjavanica,Criticallyendangered)werecaughtoncameratrapin2017;

¡ Marbledcat(Pardofelismarmorata,EN)wascaughtoncameratrapon1event;

¡ Asunbear(Helarctosmalayanus,VU)withasmallsunbearcub[est.6monthsold]wascaught on camera trap on one event; claw marks were found throughout thesign/primatetransects;

¡ Noevidencewas foundof theother two species listedasCritically Endangeredon theIUCN list, the Tapanuli orangutans (Pongo tapanuliensis, CR) nor Sumatran tiger(Panthera tigris sumatrae, CR), evidence of both species still encountered during the2014surveys;

¡ Density of resident agile gibbon (Hylobates agilis, EN) groups was found to be 2.28groups/km2and/or7.52ind/km2comparedto17.9ind/km2in2014;

¡ Siamangs (Symphalangus syndactylus, EN)were found at the edges of the SOL projectareawithadensityof0.46group/km2and/or1.28ind/km2

¡ Mitredleafmonkeys(Presbytismelalophos,EN)wereonlyoncedirectlyobservedduringthetransectsurveys,andoncecaughtoncameratrap;

¡ The Greater mouse deer (Tragulus napu) was the most common species caught oncamera traps (n=142 events 20.1% of all events), followed by the Barking deer(Muntiacus muntjac) (n=133 events 18.8% of all events) and Pig-tailed macaques(MacacanemestrinalistedasVU)(n=105events14.9%ofallevents)

¡ Sambardeer(Rusaunicolor,VU)werecaughtoncameratrapon21independentevents;

¡ Asignificantincreasewasfoundinspeciesdiversity,thenumberofevents/trapnightsandtheRelativeAbundanceIndex(RAI)ofspeciescaughtoncameratrapin2017;

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RecommendationsDue to the high occurrence of a significant number of IUCNRed Listed species aswell aswildlifeprotectedunder Indonesian law in theSOLproject area,weprovide the followingrecommendations:Restoringarborealconnectivity:ArborealconnectivityneedstoberestoredalongthenewroadconstructedtoWJP1.Thisroad cuts through the ranges of several gibbon, siamang andmitred leafmonkey groups,andhasbecomeaphysicalbarrier for theseprimates.Keyareasshouldbe replantedwithfastgrowingindigenoustreespecies[i.e.Ficusspp.,familyMoraceae]sothattherecanbeexchangeandmovementbyseveralspeciesofarborealprimatesthatresideinthearea.Theabsolutemaximumdistancebetweenlocationsofsucharborealconnectivityshouldbe250metersalongtheroad,butpreferablylessthanthis.Reducinghunting:Huntingofwildlife,specificallypoachingofsongbirds, isstill foundintheSOLprojectarea,andseveralrecommendationsaremade:

¡ Limit/haltfreeaccessusingprojectroads;thenumberofcommunitymembersthatstilluse their lands in theSOLareawillnotbe toohigh [i.e. less than100persons]andwerecommend that passes are made for these community members and that 'special'treatmentisgiven[i.e.fieldclothing,safetyoutfits]whichcouldincreasetheir 'pride' inbeingaclose'relation'ofSOLandagoodneighbour[willingtoreportillegalactivities];

¡ Developconservation/huntingagreements focusingonprotectedspecieswiththemainvillages/hamletsclosetotheprojectarea,and inreturnprovidesupport fordevelopingsmall enterprises thatwill provide sustainable protein alternatives (such as fish ponds,chickenfarming,pigfarming);

¡ To improvetheco-existenceof localcommunitieswithwildlife, it isalsorecommendedthat PT SOL invest in trialing methodologies to reduce human-wildlife conflict due topredationofcropsplantedneartheforestedge.Thiswouldbehighlyappreciatedbythecommunities,whilstPTSOLcansetanexampleofpracticalmitigationefforts.Oneofthekey species thathasbeen found to causecroppredation is listedasVulnerableon theIUCNRedList[Macacanemestrina].

Reducingillegallogging:Illegal logging around the SOL project area was still encountered and could be reducedthroughlimitingaccessbyoutsidersoverSOLprojectroads[seeabove].Further studies on the potential to improve/enhance the marketing potential ofKemenyan/Haminjon [Styrax benzoin] could be useful in this respect as well, to increaseincomepatterns,asthisnontimberforestproduct[NTFP}isspecificallygrownin/aroundtheSOL project area. This could become an interesting, rare, commodity that SOL andappropriatepartners,couldassistimprovingthemarketvalueof.

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ImprovinggarbageManagement:Rubbishwasstillencounteredintheforest(waterbottles,cigarettepack/butts,plasticbags).Instructionstostaffandcontrolmeasurescouldbebetterenforcedtoreducethis littering[i.e. by providing all staff with refillable/reusable water bottles, portable ashtrays, andbackpackstocarrylunchandtakeanyremainingpackagingoutoftheforestareas],andanyhuman litter encountered should be picked up and disposed at the SOL facilities, to beremovedonaregularbasistoalandfilloutsideoftheforestarea.GeneralComments:

• Anyotherhumandisturbance(i.e.noise,motorbikes,music),aswellasdogs,cats,andinvasivespeciesshouldbeminimizedasmuchaspossible;

• Strictregulationsshouldbeputinplaceregardingtheabove,bothforSOLworkers,contractors,visitorsandlocalcommunitiespassingthroughthearea;

• More in depth baseline information/surveys, specifically botanical, and furthermonitoring of birds and reptile/amphibians is recommended tobetter understandthe overall ecology of the area, and to develop a better understanding how tomitigatedevelopmentactivities toother speciesofconservation interestoccurringintheSOLarea;

Because of its scale and importance to the local economy, PT SOL is perfectly placed tointroduceimprovedenvironmentalpracticesbyimplementingtheaboverecommendationstoreduce,orevenbetterhalt,huntingofprotectedwildlife,reduce/haltillegallogging,andimprovegarbagemanagement.Rigorouslyimposingbestpracticesonitsownworkforceanddissemination of these amongst local communities will enhance the companies local andinternational reputation, provide a strong case study for other companies operating inIndonesia,andmodifythroughsocio-economicprojectsenvironmentallydamagingpracticesbylocalcommunities.

ThePT.SOLcompanyanditsownershave theopportunitytoplayan importantrole inthe long-term conservation of the wider Batang Toru Ecosystem, thus furtherdemonstratingandspearheadingaseriouscommitmenttoenvironmentalbestpracticesandconservation,especiallynowthattheTapanuliorangutanshavebeendescriedasanewspeciesofGreatApe,onlyfoundintheBatangToruEcosystem,with lessthan800individualsremaining.

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CreditsReportpreparedbyPanEco/YayasanEkosistemLestari:

• GabriellaM.Fredriksson• MatthewG.Nowak• GrahamUsher

Fielddatacollection&surveyteams:

• EkaSiswiyati(Primatesurveys)• DewiKurnia(Primatesurveys)• NursaniahNasution(Primatesurveys)• RomaitoSitompul(LocalassistantprovidedbySOL)• DoliHutabarat(LocalassistantprovidedbySOL)• SianPakpahan(LocalassistantprovidedbySOL)

AcknowledgementsWewould like to express our gratitude to Johannes Sagala and all SOL fieldworkerswhoassistedtheprimatesurveysandcameratrappingefforts.

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ContentsExecutiveSummary...............................................................................................................i

Keyfindings...........................................................................................................................ii

Recommendations...............................................................................................................iii

Credits...................................................................................................................................v

Acknowledgements..............................................................................................................v

ListofFigures......................................................................................................................vii

1. Introduction......................................................................................................................1

1.1 ConservationImportanceoftheBatangToruforestcomplex.................................1

1.2 BackgroundtoSurveys...............................................................................................4

1.2.1 SOLSitedescription............................................................................................4

1.2.2 Geographicalscope.............................................................................................5

1.2.3 Aimsofthebiodiversitymonitoringfieldsurveys...............................................6

1.2.4 Targetspecies.....................................................................................................6

2. Methodology....................................................................................................................7

2.1 CameraTrapping........................................................................................................7

2.1.1 Equipmentandtimeframe.................................................................................7

2.1.2 Locationsofcameratraps...................................................................................7

2.1.3 MonthlyCameraTrapChecking..........................................................................7

2.2 Primatesurveys..........................................................................................................9

2.2.1 OrangutanNestSurveys......................................................................................9

2.2.2 Gibbon/SiamangFixedCallCountSurveys........................................................10

3. Results.............................................................................................................................11

3.1 Results-CameraTrapping.......................................................................................11

3.1.1 Time-frameandnumberofindependentevents..............................................11

3.1.2 CameraTrapLocations......................................................................................11

3.1.3 Speciesencounteredoncameratraps..............................................................13

3.1.4 Relativeabundanceandspeciesencounters[2014,2016,2017].....................14

3.2 Results-LineTransectSurveys................................................................................16

3.3 Results-Orangutansurveys....................................................................................20

3.4 Results-GibbonandSiamangSurveys....................................................................20

4. Discussion.......................................................................................................................26

4.1 DiscussionwildlifemonitoringthroughPrimateSurveysandCameraTrapping...26

5. REFERENCES:...................................................................................................................30

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ListofFiguresFig.3.Locationofcameratrapplacements............................................................................12Fig.4.Locationlinetransectsandprimatelisteningposts.....................................................16Fig.5.Numberofanimalspeciessignscontactedpertransectforthe2014(top),2016(middle),and2017(bottom)fieldsurveys..............................................................................18Fig.6.Animalspeciesdirectandindirectencounterratesduringthe2014,2016,and2017systematictransectsurveys....................................................................................................19ListofTablesTable1:Mammalspecies(non-Chiropteran)encounteredintheBatangToruEcosystem(PanEco/YELdata2006-2016)andtheirIUCN/IndonesianProtectedstatus............................3Table2:Location,numberofcameraatthatlocation,beginandenddateofcameratrappingatthatlocation,coordinates,altitudeofeachcameratrappinglocation..............................11Table3:SpeciescaughtoncameratrapatSOL(3rdofMarchand14thofAugust2016),rankedbynumberofevents...................................................................................................13Table4:IUCNlistingandprotectedstatusofspeciescameratrappedatSOLin2017..........14Table6:MammalspeciesencounteredintheSOLareain2014and2016,theirnumberandpercentageofevents,andtheirRelativeAbundanceIndex[noofevents/100trapnights]...15Table7.Vertebratespeciesencountered(bothdirectlyandindirectly)duringthe2017linetransectsurveys......................................................................................................................17

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1.1 ConservationImportanceoftheBatangToruforestcomplex

The Batang Toru Ecosystem has received significant conservation attention over the lastdecade,afterthe'discovery'ofaviableorangutanpopulationinthelate1990s(Wichetal.2003). This, and follow-up surveys in the East andWest Batang Toru Forest Blocks haveresultedinthecurrentpopulationestimateofcloseto800individuals(Wichetal.2016).

The orangutans in Tapanuli, now only found in the Batang Toru Ecosystem have recentlybeendescribedasaseparatespeciesoforangutan,Pongotapnuliensis (Nateretal.2017),makingitthemostendangeredGreatApespeciesintheworld.

The West Batang Toru Forest Block (WBTFB) consists of medium elevation hill andsubmontane forest primarily covering extremely rugged terrain (400-1300m asl.), andcontainsorangutans throughout its c. 810 km2 (81.344ha) of forest.A smaller orangutanpopulation has also been encountered in the East Batang Toru forest block (forest area:54.940ha),eastoftheTarutung-Sipirokroad.

TheBatangToruEcosystem is alsohome to theCritically EndangeredSumatran tiger. ThemostrecentpublishedSumatrantigerpopulation,estimatedat300individualsinthewild,isscattered throughout the island of Sumatra (Ministry of Forestry, 2007), although thisnumberisconsideredtobeanunderestimate(Wibisonoetal.,2011).Sumatrantigershavebeen camera trapped in various locations and observed directly on rare occasionsthroughouttheWestandEastBatangToruForestBlocksoverthelastdecade.

InadditiontoTapanuliorangutans,Sumatrantigers,thepangolin(Manisjavanica)nowalsolistedCriticallyEndangered, still is foundthroughout theBatangToruEcosystem,althoughtheyarequiteheavilypersecutedfortradeintheirscalesandotherbodyparts.

AvarietyofotherEndangeredandVulnerablemammalspecies like tapirs, serow,andsunbears have been caught regularly on camera traps in an ongoingmonitoring programmecarriedoutbyPanEco/YELintheBatangToruForestEcosystem.Since2006,PanEco/YayasanEkosistem Lestari (YEL), who jointly run the Sumatran Orangutan Conservation Project(SOCP)havebeenoperatinga floraand faunamonitoringstation in theWestBatangToruForestBlock,locatedsome20kmfromtheSOLprojectarea(seeFig.1).Theforestareainbetweenthetwolocationsiscontiguousprimaryforest,atelevationsaround1000masl.

ExtensivebiodiversitysurveyshavebeencarriedoutthroughouttheBatangToruEcosystemover the years (PT. Newmont Horas Nauli/Hatfindo 2003; Conservation International2005/2006;PanEco/YEL2006-todate),withnewspeciesoffloraandfaunaencounteredoneachsurvey.

1. Introduction

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Fig.1.LocationofSOLProjectarea[purpleoutline]andSOCPFLoraandFaunamonitoringstation[reddot].Todate,throughacombinedeffortofcameratrapping,directobservationsandpreliminarystudies of small mammals a total of 60 mammal species (non-Chiropteran) have beendocumentedintheBatangToruForestcomplex(Table1).

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Table1:Mammalspecies(non-Chiropteran)encounteredintheBatangToruEcosystem(PanEco/YELdata2006-2017)andtheirIUCN/IndonesianProtectedstatus.

No Order Latin English Protected IUCN Red List1 Primata-Pongidae Pongo tapanuliensis Tapanuli orangutan 1 CE2 Carnivora-Felidae Panthera tigris sumatrae Sumatran tiger 1 CE3 Pholidota-Manidae Manis javanica Pangolin 1 CE4 Perissodactyla_Tapiridae Tapirus indicus Asian Tapir 1 EN5 Primata-Cercopithecidae Presbytis melalophos Mitred leaf monkey EN6 Primata-Hylobtaidae Hylobates agilis Agile gibbon 1 EN7 Primata-Hylobtaidae Symphalangus syndactylus Siamang 1 EN8 Artiodactyla_Cervidae Capricornis sumatrensis Serow 1 VU9 Artiodactyla_Cervidae Cervus unicolor Sambar deer 1 VU

10 Carnivora_Mustelidae Aonyx cinerea Oriental small-clawed otter 1 VU11 Carnivora_Viverridae Arctitis binturong Binturong 1 VU12 Carnivora_Viverridae Hemigalus derbyanus Banded Palm Civet VU13 Carnivora-Felidae Pardofelis marmorata Marbled cat 1 VU14 Carnivora-Ursidae Helarctos malayanus Malayan sun bear 1 VU15 Primata-Cercopithecidae Macaca nemistrina Pig tailed macaque VU16 Primata-Lorisidae Nycticebus coucang Slow loris 1 VU17 Rodentia_Muridae Maxomys whiteheadi Whitehead’s spiny rat VU18 Rodentia_Muridae Niviventer cremoriventer Dark-tailed tree rat VU19 Artiodactyla_Cervidae Muntiacus muntjac Common Barking deer 1 LC20 Artiodactyla_Suidae Sus scrofa Wild pig LC21 Artiodactyla_Tragulidae Tragulus javanicus Lesser mouse deer 1 LC22 Artiodactyla_Tragulidae Tragulus napu Greater mouse deer 1 LC23 Carnivora_Mustelidae Martes flavigula Yellow-throated marten LC24 Carnivora_Mustelidae Mustela nudipes Malay weasel LC25 Carnivora_Viverridae Arctogalidia trivirgata Small-toothed palm civet LC26 Carnivora_Viverridae Paguma larvata Masked palm civet LC27 Carnivora_Viverridae Paradoxurus hermaphroditus Common palm civet LC28 Carnivora_Viverridae Prionodon linsang Banded Linsang 1 LC29 Carnivora-Felidae Prionailurus bengalensis Leopard cat 1 LC30 Dermoptera-Cynocephalidae Cynocephalus variegatus Colugo 1 LC31 Insectivora-Erinaceidae Echinosorex gymnura Moonrat LC32 Primata-Cercopithecidae Macaca fascicularis Long-tailed macaque LC33 Rodentia_Hystricidae Hystrix brachyura Asian porcupine 1 LC34 Rodentia_Hystricidae Trichys fasciculata Long-tailed porcupine LC35 Rodentia_Muridae Leopoldamys sabanus Long-tailed giant rat LC36 Rodentia_Muridae Maxomys surifer Red spiny rat LC37 Rodentia_Muridae Niviventer fulvescens Chestnut rat LC38 Rodentia_Muridae Rattus exulans Polynesian rat LC39 Rodentia_Muridae Rattus tanezumi Japan’s house rat LC40 Rodentia_Muridae Rattus tiomanicus Malaysian field rat LC41 Rodentia_Muridae Sundamys muelleri Muller’s rat LC42 Rodentia_Rhizomyinae Rhizomys sumatrensis Sumatran Bamboo Rat LC43 Rodentia_Sciuridae Callosciurus notatus Plantain squirrel LC44 Rodentia_Sciuridae Callosciurus prevostii piceaus Prevosts squirrel LC45 Rodentia_Sciuridae Iomys horsfieldii horsfieldii Javanese flying squirrel 1 LC46 Rodentia_Sciuridae Lariscus insignis Three-striped ground squirrel 1 LC47 Rodentia_Sciuridae Nannosciurus melanotis Black-eared pygmy squirrel LC48 Rodentia_Sciuridae Petaurista petaurista Red Giant Flying squirrel LC49 Rodentia_Sciuridae Sundasciurus lowii Low's squirrel LC50 Rodentia_Sciuridae Sundasciurus tenuis Slender squirrel LC51 Scandentia-Tupaiidae Tupaia glis Common treeshrew LC52 Scandentia-Tupaiidae Tupaia tana Large treeshrew LC53 Carnivora-Felidae Pardofelis teminckii Golden cat 1 NT54 Rodentia_Sciuridae Callosciurus nigrovittatus Black banded squirrel NT55 Rodentia_Sciuridae Ratufa affinis hypoleucos Cream-coloured giant squirrel NT56 Rodentia_Sciuridae Ratufa bicolor palliata Black giant squirrel 1 NT57 Rodentia_Sciuridae Rhinosciurus laticaudatus Shrew-faced ground squirrel NT58 Rodentia_Sciuridae Sundasciurus hippurus Horse-tailed squirrel NT59 Carnivora_Viverridae Herpestes semitorquatus Collared Mongoose DD60 Rodentia_Sciuridae Exilisciurus exilis Plain pygmy squirrel DD

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1.2 BackgroundtoSurveys

In September 2013, PanEco/YEL were approached by Mott MacDonald, who had beencommissioned by Sarulla Operations Ltd (SOL) to coordinate biodiversity monitoring fieldsurveys at their Sarulla geothermal field, to assist with these surveys. An initialreconnaissance(recce)wascarriedout inNovember2013,followedbymoreintensivelinetransect and primate callmonitoring surveys in June 2014. BetweenNovember 2013 andJune2014acameratrappingprogrammewasrun.

In2016PanEco/YELwasaskedbySOLtoassistwithfurtherbiodiversitymonitoring,whereitwasdecidedthatSOL'senvironmentaldepartmentwouldcarryoutcameratrappingeffortsthemselvesinthefield,withPanEco/YELassistingwithidentificationandanalysesofcameratrappingdata,andPanEco/YELfocusingadditionallyonrepeatprimatesurveys.

In 2017 PanEco/YEL continued as per arrangement thatwasmade in 2016, assistingwithidentificationandanalysesofcamera trappingdata,andPanEco/YELstaffcarryingout therepeatprimatesurveysinthefield.

1.2.1 SOLSitedescription

The following description of the site, geographical location, the aims of the monitoringsurveys, and list of species of interest are taken from the March 2014Mott MacDonaldproposalontheBiodiversityMonitoringMetholodogy(initalics).

TheoverallSarullaGeothermalProjectcomprisestwogeothermalfields(NamoraILangitor"NIL"field,andSilangkitangor"SIL"field),eachconsistingofapowerstation(twoatNIL),production and re-injection wells, connecting pipeline, and a transmission line to thePerusahaanListrikNegara(PLN)powersub-station.TheProjectislocatedbetweentheEastandWestBatangToruForestBlocksintheSarullavalley(Figs.1and2).

Themajority(approximately90%)oftheinfrastructurewillbelocatedwithinexistingareasofModifiedhabitats(asdefinedunderIFCPerformanceStandard6)andarerepresentedbyfourvegetationcommunities:yardvegetation,fieldvegetation,rubberplantationandmixedplantation vegetation. These habitats have been assessed as not being of significantconservation importance and the impact upon them is considered to be negligible(BiodiversityImpactAssessment,ERM,2013).Theseareaswillnotbesurveyedaspartofthisbiodiversitymonitoringprogram.

Approximately10%oftheProjectwillbelocatedwithinanareaidentifiedasNatural/CriticalNaturalHabitat(IFCPS6).ThisareaissituatedaroundtheinfrastructureofNIL1andWJP1.The habitatswithin the Project footprint comprise secondary lowermontane (dipterocarp)forest,naturalscrub(padangvegetation),heathforest,non-naturalscrubandmixedforest(Habitat Condition Assessment, Mott MacDonald, 2013). Collectively this area coversapproximately8ha.Thebiodiversitymonitoringprogramwilltargetthehabitatswithintheseareas.

Approximately92haof theProject is locatedwithin theWesternBatangToruForestBlock(WBTFB). This area is situated around the infrastructure of the NIL Geothermal Field. ThehabitatswithinandadjacenttotheProjectcomprisesecondary(dipterocarp)forest,naturalscrub (padangvegetation), scrub forest (heath forest),non-natural scrub,andmixed forest

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(Mott MacDonald, 2013). The biodiversity monitoring program will target these habitatswithinthisarea.

1.2.2 Geographicalscope

The geographical scope of the surveyscomprisedthreezonesasfollows:

Zone1:Habitatswithin the footprintof theinfrastructure identified as Natural/CriticalNaturalHabitat(NIL1andWJP1).

Zone 2: Habitats within 500m of thefootprint of the infrastructure identified asNatural/CriticalNaturalHabitat.

Zone 3: Habitats over 500m from thefootprint of the infrastructure identified asNatural/Critical Natural Habitat. Thesecomprise the wider landscape within theBatangToruForest.

The biodiversity monitoring field surveystargetedthehabitatslocatedwithinZones1& 2 (collectively hereafter the ‘ProjectArea’),aswellasZone3astheseareasareconsidered part of the ranges of variousspeciesoccurringinthe'ProjectArea'.

Fig.2.LocationofSOLProjectarea

In the SOL Biodiversity Action Plan and Biodiversity Off-set Management Plan (2015) it isstatedthat“IftheBatangToruOrang-Utanwillofficiallygainthestatusofadistinctspecies,theCHA[CriticalHabitatAssessment]mightbere-evaluated.”(p.34).

As the Tapanuli orangutanhasnow formally beendescribed as a newgreat ape species,Pongo tapanuliensis (Nater et al. 2017), the Critical Habitat Assessment should be re-evaluated. Not only is the Batang Toru Ecosystem the last habitat for the Tapanuliorangutan,thissepciesisnowalsothemostendangeredGreatApespeciesintheworld.

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1.2.3 Aimsofthebiodiversitymonitoringfieldsurveys

Theaimsofthebiodiversitymonitoringfieldsurveysareasfollows:

To provide further baseline data on the likely presence and habitat usage of species ofconservationimportance(‘TargetSpecies’),whichareknownorhavethepotentialtooccurintheProjectArea.Thisincludes:

− Creatinghabitatandspeciesdistributionmaps.

− Interpretingdata collected from the field surveys in the context of theProject andthewiderconservationobjectivesoftheBatangToruEcosystem.

Tomonitor the likelyeffectsof theProjectonTargetSpeciesandto informchanges to theEnvironmentalManagementPlanaswellasrequirementswithintheBiodiversityActionPlanandBiodiversityOff-setManagementPlan.

1.2.4 Targetspecies

Sevenspecieswereinitially identifiedasoccurring,orhavingthepotentialtooccur,withintheProjectAreaandweresaidtobelistedbytheIUCNRedListasCriticallyEndangeredorEndangered.Thisinitiallistoftargetspecieswasasfollows:

1. Sumatranorang-utan(Pongotapanuliensis)[CriticallyEndangered,IUCNRedList];2. Sumatrantiger(Pantheratigrissumatrae)[CriticallyEndangered,IUCNRedList];3. Malayanpangolin(Manisjavanica)[CriticallyEndangered,IUCNRedList];4. Asiantapir(Tapirusindicus)[Endangered,IUCNRedList];5. Mitredleaf-monkey(Presbytismelalophos)[Endangered,IUCNRedList];6. Siamang(Symphalangussyndactylus)[Endangered,IUCNRedList];7. Agilegibbon(Hylobatesagilis)[Endangered,IUCNRedList].

AlistofotherspeciesidentifiedwithintheProjectareawasputforward,mostrecognizedasspeciesofconservationimportanceandlistedasVulnerableontheIUCNRedList,exceptforthewild pig, an important prey species for Sumatran tiger. Thesewere to be consideredsecondaryspecies,toberecordedduringthebiodiversitymonitoring,butnotbesubjecttospecies-specificsurveys:

1. Marbledcat(Pardofelismarmorata)[Vulnerable,IUCNRedList];2. Sumatranserow(Capricornissumatraensis)[Vulnerable,IUCNRedList];3. Sambardeer(Rusaunicolor)[Vulnerable,IUCNRedList];4. Malayansunbear(Helarctosmalayanus)[Vulnerable,IUCNRedList];5. Binturong(Arctictisbinturong)[Vulnerable,IUCNRedList];6. Slowloris(Nycticebuscoucang)[Vulnerable,IUCNRedList].7. Wildpig(Susscrofa).

Anumberofotherspecies listedasVulnerableunderthe IUCNRedListarealsoknowntooccurintheBatangToruEcosystem(seeTable1).

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2.1 CameraTrapping

Cameratrapsarethepreferredsurveytechniqueforsomeofthemorecrypticfauna(e.g.,tiger,marbledcat,pangolins, tapirs).PanEco/YELhavebeenoperatingcameratraps intheBatangToruForestComplexstartingin2008.Cameratrapswereutilizedforthebiodiversitysurveys in the SOL project area to determine the presence, distribution, and relativeabundanceofvariouscrypticfaunalspecies.TechniquesfollowedherearesimilartothosedescribedbyAncrenazetal.(2012).

2.1.1 Equipmentandtimeframe

Atotalof10BushnellTrailCamcameratrapswereusedforthecameratrappingeffortsin2017. These camera's all use amotion sensor and hyper passive infrared sensor (PIR) todetectheattotriggerthecameratotakeanimage.Thesecamerasareintheorylesspronetofalsecaptures.Allcamera'susedhighspeedSDcards[8or16GB]andweretiedtotreeswithpythonlocks.

Cameratrappingcommencedon21stofFeb2017andcontinuedtill11thofAugust2017.

2.1.2 Locationsofcameratraps

Cameratrappingsurveyaimedtocoveracombinationofhabitattypesandlocationswithinthe forest areas of NIL1 and WJP1. The same locations were used as in the monitoringsession of 2016. The 10 camera trapswere deployedwithin the ‘Project Area’, placed atleast100metersfromoneanother.

2.1.3 MonthlyCameraTrapChecking

Followingplacement, thecamera-trapswererunbetween2-3monthsatasingle location,depending on previous results. Camera-trapswere checked approximately once amonth,andthefollowingactionsweretaken:

¡ Checkandreplacebatteries;¡ ChangeSDcard;¡ Ensure that the camera is still functioning and that there is nothing obstructing the

camera’slens.

After each camera trap session the following datawas be recorded for each camera trapnight:

¡ Speciescaptured;¡ Thenumberofcaptureeventsperspecies;¡ Thenumberofindividualsperevent.

Each period that one camera trap was left in the field for approximately 1 month waslabelled as a separate a "session". A camera trap could be left for another session at the

2. Methodology

8

same location if several or interesting animals were photographed during the previoussession.

Locations for placement of the camera trapswere chosen tomaximize results, thus trapswereplaced in locationswith tracks, scatsoranimal trails. Thecamera trapwasgenerallyplaced50cmabove the ground to try to detect animals of various size, although thiswaspartlydependentonslopesinthedifferentlocations.

Cameratrapsweresettotakethreepictureeachtimethesensorwastriggeredtomaximizechances of identification. Identification of species was assisted with the help of severalmammalidentificationbooks:

− AfieldguidetotheMammalsofBorneobyQ.PhillipsandK.Phillips(2016);

− AfieldguidetotheMammalsofBorneobyJ.Payne,C.Francis,K.Phillips(1998);

− AfieldguidetotheMammalsofSouth-EastAsiabyC.Francis(2008).

Some pictures were sent to specialist to assist with identification [mainly Tupaiidae andMuridae].

Wedefinedaspeciesrecordingasan‘event’whenaphotograph(orseriesofphotographs)ofanindividualspecies(countingnumberofindividualsofthatspecies)wasrecordedbythesamecameraatonelocation,includingallotherpicturesofthesamespeciestakenwithinatimeperiodof30minutesat the samecameraplacement (O'Brienet al. 2003, Linkie andRiboud2011).Photographsthatwererecordedwithin30minofapreviousphotographofthe same species, and at the same camera placement, were not recorded as an event,becausetheywerenotconsideredtobeindependentspeciesevents.Wereportnumberofanimaldetections [events]andcalculateRelativeAbundance Indices(RAI)(Carboneetal.2001,O’Brienetal.2003)forthemostfrequentlyrecordedspecies,asameasure tocompare frequencies/ relativeabundancesbetween2014,2016, and2017.TocomputetheRAIforeachspecies,alldetectionsforeachspeciesaresummedforallcameratrapsoveralldays,multipliedby100,anddividedbythetotalnumberofcameratrapnights.

9

2.2 Primatesurveys

Primatesurveysweretobeundertakenbetween15thofJulyand12thofAugust2017.Thefollowingmaterialsandmethodsweretobeused:

2.2.1 OrangutanNestSurveys

Using orangutan nest surveys, relative orangutan densities were to be calculated for theProjectareafollowingapreviouslypublishedprotocol(e.g.vanSchaiketal.,1995,Buijetal.,2002, Buij et al., 2003, Wich et al., 2004). This methodology relies on the fact thatorangutansconstructnestsdaily,whichareusedatnightandalsosometimesduringthedayfor resting (van Schaik et al., 1995, Singleton, 2000). Using nest counts instead of liveencounterswithorangutans ispreferredhereduetothe lowdensityoforangutans,whichmakesdensityestimatesbasedonliveencountersaverytimeconsumingexercise.

Nestcountsweretobeconductedalong22randomlyplacedtransects intheProjectarea,followingmethodsofMarshalletal. (2008)andBucklandetal. (2010),witheach transectbeing500minlength,withaminimumof200metersbetweentransects.Alllinetransectsshouldbeonly largeenough forobservers towalkwithoutdisruption. It is recommendedthat the surveyorswait a week after the line transects are cut before they start the linetransectsurveys.Thisallowstheanimalpopulationthatmayhavebeendisturbedduringthemakingofthelinetransects,tocomebackintothearea.

Duringnest counts, twoexperiencedobservers slowlywalkedon transectsand record theperpendiculardistanceofall identifiednests.Perpendiculardistancesaremeasuredwithahipchain.Eachtransectwaswalkedtwice,onceineachdirection.

Orangutandensitywasestimatedfromnestcountsusingthefollowingformula:

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

inwhich:

d=orangutandensity(individuals/km2),N=numberofnestsobservedalongthetransect,L=lengthofthetransectcovered(km),w=estimatedwidthofthestripofhabitatactuallyvisuallycovered(km),p=proportionofnestbuildersinthepopulation,r=rateatwhichnestsareproduced(n/day/individual),andt=timeduringwhichanestremainsvisible(indays).

Estimating strip width (w): Using themeasured perpendicular distance of nests from thetransectline,(w)wasestimatedusingthecomputerprogramme''Distance6.0''(Thomasetal.,2001).

Parameters(p)and(r):Intwolong-termstudiesofSumatranorangutans,roughly10%ofthepopulation was comprised of non-nest building infants, and as such, (p) was set at 0.9.Conversely,inthesametwoSumatranorangutanpopulations,thenumberofnestsbuiltperday(r)wasfoundtobeapproximately1.7(vanSchaiketal.,1995).

10

Nestdecayrate(t):AstudybyBuijetal.(2003)foundthatthereisanegativerelationshipbetween (t) (i.e., thenumberofdaysanest remainsvisibleafter ithasbeenconstructed)and topsoil pH. The rationale behind this relationship is that nest decay is thought to bepartlydependentonthehardnessofthewoodofthenesttrees,andthehardnessofwoodisthoughttobehigherwithadecreaseintopsoilpH(Buijetal.2003).PHvalueshavebeenmeasuredatvariouslocationsneartheYEL/SOCPresearchstationanddetaileddataonnestdecay rates in the Batang Toru forest have been calculated from previous studies (YELunpublisheddata).

2.2.2 Gibbon/SiamangFixedCallCountSurveys

While gibbons and siamangs can also be surveyed via line transects, the abundanceestimatesthatareobtainedfordirectcontactsurveysareconsideredaminimumestimate,as these species are extremely cryptic. However, both these species have distinctive callsandthusthedensityofgibbonandsiamanggroupswastobecalculatedusingthefixedcallcountmethodologyestablishedbyBrockelman&Ali (1987). Inparticular,aseriesof threelistening stations (all consisting of a set of three listening posts each), were each to bemonitored for five consecutive days. Each survey day, between 05:00 – 12:00, surveyorsfrom each listening post recorded the time of a group’s call, the species (i.e., gibbon orsiamang), the compass bearing, and the estimated distance. Via triangulation, group callswere thenmarked on amap inGIS, and the total number of gibbon and siamang groupsheardwasestimatedforeachlisteninglocation.

In order to control for call point location estimation errors, vocalization points wererestricted towithina500meter radius fromanygiven listeningpost.Additionally,agivenvocalizationhadtohavebeenheardfromatleasttwolisteningposts.Theeffectivelisteningarea(E)forbothgibbonsandsiamangswasthencalculatedbydrawingapolygonaroundalluseablevocalizationpoints.

Groupdensityestimates(D)willbecalculatedusingtheequation:

D=n/[p(m)xE](Brockelman&Ali,1987)

where:

n=thenumberofgroupsheard,

p(m)=theestimatedproportionofgroupsexpectedtosingatasurveylocationduringasamplingperiodofmdays,

E=Effectivelisteningarea.

AlsofollowingBrockelman&Ali(1987),p(m)wasdeterminedusingtheequation:

p(m)=1-[1-p(1)]m

where:

p(1)=theaverageprobabilityofsingingforanygivenday,

m=thenumberofsurveydays.

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3.1 Results-CameraTrapping

3.1.1 Time-frameandnumberofindependentevents

Between21stofFebruaryand12thofAugust2017,atotalof931trapnightswerecarriedout. During this period, a total of 3131 pictures were obtained of mammal/bird species,fromatotal706independentevents.Intotalcloseto79.000picturesweretaken,includingcameraerrors,butallpicturesneededtobeviewed.

3.1.2 CameraTrapLocations

A total of 10 different locations were used for placement of the camera traps. Table 2describes the beginning and end date of placement at that location, and altitude.Unfortunatelynovegetationdescriptionwasprovidedforthecameratrapplacements.Fig.3showsthelocationsofcameratrapplacementinrelationtoNIL1andWJP.

Table2:Location,numberofcameraatthatlocation,beginandenddateofcameratrappingatthatlocation,coordinates,altitudeofeachcameratrappinglocation.

Locat. NORTHING EASTING LAT_2 LONG_2 Alt Datestart Datefinish TotalTrapnights

L1 207284 502283 1.87535 99.02053 930 10-Mar-17 11-Aug-17 141L2 207211 502540 1.87470 99.02284 943 10-Mar-17 23-Jul-17 45L3 207932 501246 1.88122 99.01120 1065 27-Mar-17 1-Aug-17 127L4 207954 501450 1.88142 99.01304 1078 11-Mar-17 12-Aug-17 103L5 207580 503048 1.87804 99.02740 13-Mar-17 11-Aug-17 115L6 208001 502914 1.88184 99.02620 918 13-Mar-17 8-Apr-17 28L7 207152 502295 1.87416 99.02060 916 10-Mar-17 16-Jul-17 99L8 207199 502691 1.87458 99.02420 826 10-Mar-17 22-Jul-17 49L9 207755 503315 1.87962 99.02980 945 13-Mar-17 11-Aug-17 159L10 207816 503253 21-Feb-17 25-Apr-17 65

TOTAL 931

3. Results

12

Fig.3.Locationofcameratrapplacements.Numbers(L1-L10)refertoTable2.

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3.1.3 Speciesencounteredoncameratraps

Aminimumof20mammalspecieswerephotographedandidentifiedtospecieslevel(table3),butseveralTupaiidae,SciuridaeandMuridaespeciescanbeaddedtothislist.

The threemostcommonspeciesphotographedmadeup53.8%ofallevents.Thesewerethe Greater mousedeer Tragulus napu (n=142 events, 20.1%), RedMuntjac/Barking deerMuntiacus muntjac (n=133 events, 18.8 %) and Pig-tailed macaques,Macaca nemestrina(n=105 events, 14.9%), followed by Muridae [rats and mice] and treeshrews [most notidentifiedtospecies,butatleast3specieswereamongstpicturesthatcouldbeidentified].

Table3:SpeciescaughtoncameratrapatSOL(21stFeband12thofAugust2017),rankedbynumberofevents.Ungulates [4 species]madeup44.3%of all camera trap events,whereas carnivores onlymade up 2.3 % of events, but 8 species was caught on camera trap in 2017, with 16individualevents.Birdsmadeup10.6%ofevents(n=75).SeveralinterestingbirdsfromtheFamilyPhasianidaewerecaughtoncamera trap,namely theRed Junglefowl, theSumatranpeacockpheasantandtheFerruginousPartridge.

SpeciesEnglish SpeciesLatin L1 L2 L3 L4 L5 L6 L7 L8 L9 L10 Events %ageevents1 GreaterMousedeer Tragulusnapu 57 15 6 64 142 20.12 RedBarkingdeer Muntiacusmuntjac 4 3 60 20 15 2 8 3 17 1 133 18.83 Pig-tailedmacaque Macacanemestrina 20 4 20 12 5 3 19 2 16 4 105 14.94 Mice&Rats Muridaespp. 3 1 35 13 1 11 1 65 9.25 Treeshrews Tupaiaspp. 1 3 47 1 1 9 1 63 8.96 Sambardeer Cervusunicolor 3 2 1 6 1 1 4 3 21 3.07 Three-stripedgroundsquirrel Lariscusinsignis 19 19 2.78 Wildpig Susscrofa 1 1 6 2 7 17 2.49 Squirrel_genusSundasciurus Sundasciurusspp. 10 5 15 2.110 Linsang Prionodonlinsang 2 4 1 7 1.011 Asianporcupine Hystrixbrachyura 6 6 0.812 MaskedPalmCivet Pagumalarvata 3 3 0.413 Pangolin Manisjavanica 1 1 2 0.314 Squirrel_genusCallosciurus Callosciurusnotatus[spp] 1 1 2 0.315 Small-toothedpalmcivet Arctogalidiatrivirgata 1 1 0.116 Yellow-throatedmarten Martesflavigula 1 1 0.117 MalayWeasel Mustelanudipes 1 1 0.118 Sunbear Helarctosmalayanus 1 1 0.119 Marbledcat Pardofelismarmorata 1 1 0.120 Leopardcat Prionailurusbengalensis 1 1 0.121 Low'ssquirrel Sundaciuruslowii 1 1 0.122 Slowloris Nycticebuscoucang 1 1 0.123 Mitredleafmonkey Presbytismelalophos 1 1 0.124 Mammalunidentified Mammalunknown 3 3 5 11 1.625 Bat_unidentified Chiroptera 1 1 0.126 Snake_unidentified Snakesp. 1 1 0.127 Man Homosapiens 2 1 3 0.428 Domesticdog Canisdomesticus 5 1 6 0.8

1 Emeraldpigeon Chalcophapsindica 1 2 2 1 19 25 3.52 Crestedpartridge Rollulusrouloul 11 1 2 1 15 2.13 Sumatranpeacockpheasant Polyplectronchalcurum 1 14 15 2.14 RedJunglefowl Gallusgallus 3 3 0.45 Ferruginouspartridge Caloperdixoculea 2 2 0.36 CrestedGoshawk Accipitertrivirgatus 1 1 0.17 Birdunidentified Avesunidentified 1 10 1 2 14 2.0TOTAL TOTALEVENTS 43 13 272 58 33 77 51 6 143 10 706 100

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A total of 62.5 % of events were photographs of species listed as Critically Endangered,EndangeredorVulnerableunderthe IUCNRedList,orspeciesprotectedunder Indonesianlaw(Table4).

Table4:IUCNlistingandprotectedstatusofspeciescameratrappedatSOLin2017.

3.1.4 Relativeabundanceandspeciesencounters[2014,2016,2017]Significantlymorespecieswerecaughtoncameratrapin2017thanin2014or2016.Therespecifically seemed to a variety of species in the Ordo Carnivora [Felidae, Viverridae,Mustelidae] documented in 2017 through camera trapping. The one carnivore speciescaught on camera trap consistently since 2014 is the Linsang (Prionodon linsang). Severalotherpeciescaughtoncameratrapin2014butnotin2016,butnowagainin2017includedthe Masked palm civet (Paguma larvata), the Small-toothed palm civet (Arctogalidiatrivirgata), the Yellow-throatedmarten (Martes flavigula) and theMalayweasel (Mustelanudipes). This year two cat specieswere caught on camera trap aswell, themarbled cat(Pardofelismarmorata) and the leopard cat (Prionailurus bengalensis). In addition for thefirsttimeasunbearwithcub(Helarctosmalayanus)wasalsocaughtoncameratrap,aswellastheYellow-throatedmarten(Martesflavigula).TheRelativeAbundanceIndex(RAI)ofmostspecieswassignificantlyhigherin2017thanin2016 (table 6). Differences in RAIs may be a result of a number of factors includingdifferences indetectionprobabilitiesbetweensurveys,hencewereportonlythestrongestdifferencesinRAIasanindicationoftruedifferencesinspeciesabundance.

Species_English Species_Latin IUCN Protected Events %ageeventsPangolin Manisjavanica CR 1 2 0.3Mitredleafmonkey Presbytismelalophos EN 1 1 0.1Sambardeer Cervusunicolor VU 1 21 3.0Sunbear Helarctosmalayanus VU 1 1 0.1Marbledcat Pardofelismarmorata VU 1 1 0.1Slowloris Nycticebuscoucang VU 1 1 0.1Pig-tailedmacaque Macacanemestrina VU 105 14.9Greatermousedeer Tragulusnapu LC 1 142 20.1Barkingdeer Muntiacusmuntjac LC 1 133 18.8Three-stripedgroundsquirrel Lariscusinsignis LC 1 19 2.7Linsang Prionodonlinsang LC 1 7 1.0Asianporcupine Hystrixbrachyura LC 1 6 0.8Crestedgoshawk Accipitertrivirgatus LC 1 1 0.1Leopardcat Prionailurusbengalensis LC 1 1 0.1

TOTALEVENTS 441 62.5

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The largestdifference inRAIwasobserved for theGreatermousedeer. This specieshadaRAI of 15.3 mousedeer/100 trapnights, versus very low RAI's in prior years. The RAI ofbarkingdeer increased from4.5barkingdeer/100 trapnights in2016 to14.3barkingdeerevents/100trapnightsin2017.

Table5:MammalspeciesencounteredintheSOLareain2014,2016and2017,theirnumberandpercentageofevents,andtheirRelativeAbundanceIndex[noofevents/100trapnights].

Species ScientificnameNoofevents

Noofevents

Noofevents % % % RAI RAI RAI

IUCNstatus

Protected

2017 2016 2014 2017 2016 2014 2017 2016 2014RedMuntjac/Barkingdeer Muntiacusmuntjac 133 30 154 18.8 25.6 29.2 14.3 4.5 15.7 LC XPig-tailedmacaque Macacanemestrina 105 30 142 14.9 25.6 26.9 11.3 4.5 14.4 VUSambardeer Rusaunicolor 21 16 31 3.0 13.7 5.9 2.3 2.4 3.2 VU XGreatermouse-deer Tragulusnapu 142 5 24 20.1 4.3 4.6 15.3 0.8 2.4 LC XWildpig Susscrofa 17 4 6 2.4 3.4 1.1 1.8 0.6 0.6 LCThree-stripedgroundsquirrel Lariscusinsignis 19 3 9 2.7 2.6 1.7 2.0 0.5 0.9 LC XBandedLinsang Prionodonlinsang 7 3 6 1.0 2.6 1.1 0.8 0.5 0.6 LC XShrew-facedgroundsquirrel Rhinosciuruslaticaudatus none 2 3 1.7 0.6 0.3 0.3 NTLargeTreeshrew Tupaiatana none 2 none 1.7 0.3 LCPangolin Manisjavanica 2 1 3 0.3 0.9 0.6 0.2 0.2 0.3 EN XMalayanPorcupine Hystrixbrachyura 6 1 0.8 0.9 0.6 0.2 LCMarbledcat Pardofelismarmorata 1 none 2 0.1 0.4 0.2 VU XLeopardcat Prionailurusbengalensis 1 0.1 LC XMaskedpalmcivet Pagumalarvata 3 none 3 0.4 0.6 0.3 LCCommonpalmcivet Paradoxurushermaphroditus none none 4 0.8 0.4 LCMalayweasel Mustelanudipes 1 none 1 0.1 0.2 0.1 LCSmall-toothedpalmcivet Arctogalidiatrivirgata 1 none 1 0.1 0.2 0.1 LCSunbear Helarctosmalayanys 1 none none 0.1 VU XYellow-throatedmarten Martesflavigula 1 none none 0.1 LCSlowloris Nycticebuscoucang 1 none none VU XMitredleafmonkey Presbytismelalophos 1 none none EN XRat/mice_unidentified Muridae 65 4 12 9.2 3.4 2.3 7.0 0.6 1.2Mammal_Unidentified Mammalia 11 3 15 1.6 2.6 2.8 1.2 0.5 1.5Squirrels_others Sciuridae 18 2 2.5 1.7 1.9 0.3Treeshrews_unidentified Tupaiidae 63 2 69 8.9 1.7 13.1 6.8 0.3 7.0Bats_unidentified Chiroptera 1 none 2 0.1 0.4 0.2Man&dogs Homo&Canis 9 none 23 1.2 4.4 2.3

Emeralddove Chalcophapsindica 25 4 4 3.5 3.4 0.8 2.7 0.6 0.4RedJunglefowl Gallusgallus 3 2 0.4 1.7 0.3 0.3 LCSumatranpeacockpheasant Polyplectronchalcurum 15 1 1 2.1 0.9 0.2 1.6 0.2 0.1 LCFerruginousPartridge Caloperdixoculea 2 1 0.3 0.9 0.2 0.2 NTCrestedpartridge Rollulusrouloul 15 2.1Eyebrowedthrush Turdusobscurus 1 0.2 0.1Forestwagtail Deonanthusindicus 1 0.2 0.1Siberianthrush Zootherasiberica 1 0.2 0.1CrestedGoshawk Accipitertrivirgatus 1 0.1 XBirds_unidentified Aves 14 1 7 2.0 0.9 1.3 1.5 0.2 0.7Snake_unidentified Serpentes 1 0.2 0.1Skink/Lizard_unidentified Reptilia 1 1 0.1 0.2 0.1TOTALEVENTS 706 117 527 100 100 100

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3.2 Results-LineTransectSurveysAtotalof22transects(each500minlength)weresystematicallywalkedineachdirection,for a total survey effort of 22 km. Four primary habitat types were surveyed while ontransect,including1)primaryforest,2)secondaryforest,3)Arangforest,and4)Kemenyangardens(Fig.15).FordescriptionsofArangforestandKemenyangardens,seeAppendixIII.

Fig.4.Locationlinetransectsandprimatelisteningposts

17

During the transect walks/surveys. efforts weremade to collect data on all animal directcontactsandindirectsigns(e.g.,feces,feedingremains,footprints,scratchmarks,nests,andvocalizations).Fromthe11kmwalked,therewereatotalof109directandindirectanimalsignsrecorded(Table6).

Table6.Vertebratespeciesencountered(bothdirectlyandindirectly)duringthe2017linetransectsurveys.Thisrepresentedanincreasefromthe53signsrecordedinthe2014surveyandthe63signsrecordedinthe2016survey.Nevertheless,whilethenumberofcontactshasincreased,thenumberofspeciespertransect is low(1.2species/transect±0.7species/transect),relativeto the 2014 (1.5 species/transect ± 1.2 species/transect) and 2016 (1.5 species/transect ±2.0 species/transect) field seasons (Table 7; Fig. 5). Perhaps the large number of speciescontactedinearlysurveysis indicativeofdisturbancerelateddensitiesinsomeareas,withthecurrentsituationpotentially indicatinganimalsbeingmorewaryofhumans,and/orforsomeswitchingtomorecrepuscularornocturnalbehaviourtoavoidhumans.

Transect WildBoarLong-tailed

Macaque

AgileGibbon Muntjac Hornbill

SambarDeer Siamang

MitredLeaf

MonkeySunBear

JavanPangolin

Squirrel(sp.?)

Snake(sp.?) Total

T1 3 1 4

T2 1 2 3

T3 3 1 1 1 6

T4 1 1 2 1 5

T5 2 2

T6 1 2 3

T7 1 1

T9 1 2 1 4

T10 1 1 2 1 1 6

T11 1 5 1 4 1 12

T12 3 3

T13 1 2 1 4

T14 3 1 6 10

T15 2 1 3

T16 1 1 3 1 6

T17 1 1 2 2 1 1 8

T18 1 1 1 3

T21 2 2 3 7

T22 2 1 1 4

T23 2 2 4

T24 2 2 1 1 1 7

T25 1 1 2 4

Total 17 1 3 34 3 23 2 1 21 2 1 1 109

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Fig.5.Numberofanimalspeciessignscontactedpertransectforthe2014(top),2016(middle),and2017(bottom)fieldsurveys.The most frequently contacted animal species, either directly and/or indirectly, was themuntjac (31.2% of all contacts), followed by sambar deer (21.1%), sun bear (19.3%),wildboar(15.6%ofallcontacts),agilegibbon(2.8%),unidentifiedhornbill(2.8%),siamang(1.8%),pangolin (1.8%),mitred leafmonkeys (0.9%), long-tailedmacaque (0.9%), an unidentified

19

snakespecies(0.9%),andanunidentifiedsquirrelspecies(0.9%ofallcontacts)(Table7;Figs.5and6).

Table7.Linetransectsurveysummarystatistics.Therewasasignificantdifferenceinthespeciesencounteredduringthesystematictransectsurveysconductedin2014,2016,and2017(Tables6-7;Figure5-6).Forinstance,pheasants,pig-tailedmacaques,serow,andmousedeerwereencounteredinoneofthetwoprevioussurveys,butnotcontactedin2017.Ontheotherhand,long-tailedmacaquesandpangolinswe not encountered in either 2014 or 2016, but were encountered in 2017. Wild boarsmaintained a high contact rate with that of the 2016 survey, muntjac encounter ratesappearto increaseconsistentlysince2014,andbothsambardeerandsunbearencounterratesappearedtorecoverafteraninitiallowin2016.

Fig.6.Animalspeciesdirectandindirectencounterratesduringthe2014,2016,and2017systematictransectsurveys.SeeTables7and8aboveforthesummaryfigures.

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3.3 Results-OrangutansurveysNoorangutannestswereencounteredduring the2017 surveys,neitherduring systematictransectsurveysnorduringreccewalksbetweentransects.

3.4 Results-GibbonandSiamangSurveysFollowing the fixed call count methodology established by Brockelman and Ali (1987), aseries of 3 listening stations (all consisting of a set of three listening posts each) weremonitoredforatotalof12surveysdaysfromthehoursof0500-1200duringthe2017fieldseason.Datarecordedforeachlisteningpostincludedthetimeofthegroupcall,thespecies(i.e.agilegibbonorsiamang),thecompassbearing,andtheestimateddistance.

Fig.7.Agilegibbons(Hylobatesagilis)hereadarkandlightform,photographedintheBatangToruEcosystem.PictureSugestiM.Arif.

21

Fig.8.Siamang(Symphalangussyndactylus)photographedintheBatangToruEcosystem.PictureJamesAskew.During the 2017 survey period, an average of 51 (range: 44-55 calls) agile gibbonvocalizationswereheardperlisteningarray,whileanaverageof3(range:2-3calls)siamangvocalizationswereheardperlisteningarray(Figs.7&8andmapFig.9).Agilegibbongroupswereheardtocallthroughoutthethreesurveyedareas,withanumberofcallsbeingheard<100mfrombothNIL1andWJP1.SiamangswereonlyheardcallingattheedgesoftheSOLprojectarea,withtheclosestcallsbeingheardjust<1000mfrombothNIL1andWJP1.Forthemoment, itappears thatagilegibbonandsiamangcalling locationshavenotyetbeenimpactedbyinfrastructuredevelopment.Onaverage,gibbonsstartedcallingat07:12(range-05:01-11:14),whereassiamangsstartedcallingat09:01 (range -06:40-10:42).This is very similar to theaverages reported for the2014and2016fieldseasons,whereagilegibbonaveragecallstarttimeswere06:44in2014and07:06in2016,andsiamangaveragecallstarttimeswere09:01in2014and9:03in2016.WhencomparedtocalltimesfromSOCP’slong-termmonitoringstation,vocalizationtimesfrom both agile gibbons and siamangs from the SOL 2017 survey fell within the range oftheirSOCPcounterparts(Figs.10and11).Viatriangulation,groupcallsweremarkedontoamapinaGISandthetotalnumberofagilegibbon and siamang groupsheardwas estimated for each listening location.Weestimatethatthedensityofagilegibbonsgroups is2.28groups/km2(range:2.24-2.36groups/km2)(Table9).Usinganaverageagilegibbongroup sizeof3.3 individuals (i.e., calculated fromdirectobservationwith12gibbongroupswithintheSOCPBatangToruresearcharea), it isestimatedthatthereareanaverageof7.52individuals/km2adjacent/withintheSOLprojectarea. Similarly, the average density of siamang groups is estimated at 0.46 groups/km2

22

(range: 0.00-0.91 groups/km2) (Table 9). Using an average siamang group size of 2.8individuals(i.e.,calculatedfromdirectobservationwith9siamanggroupswithintheSOCPBatang Toru research area), it is estimated that there are an average of 1.28 individuals/km2adjacent/withintheSOLprojectarea.

Fig.9.Agilegibbon(Hylobatesagilis)andsiamang(Symphalangussyndactylus)callinglocations,estimatedfromeachlisteningpostusingdistanceandcompassbearing.While average densities for the overall project area are similar to that calculated for the2014 and 2016 field seasons, the calling rate of agile gibbon vocalizations and a lack ofsiamang callswithin theeffective listening areaof vocal arraynumber two (i.e., the vocalarray closest to the project area) suggests that both gibbons and siamangs might bedisplaying early signs of disturbance, possibly related to the development of projectinfrastructureand/ortheregularoperationsofthefacilities(Tables9-10).

23

Fig. 10.BoxandwhiskerplotsofagilegibboncalltimesforvariousfieldsurveysinBatangToru.Notethesimilarityincalltimes.

Fig.11.BoxandwhiskerplotsofsiamangcalltimesforvariousfieldsurveysinBatangToru.Notethesimilarityincalltimes.

5:00

6:00

7:00

8:00

9:00

10:00

11:00

12:00

Gibbon(

SOCP)

Gibbon(

SOL-20

14)

Gibbon(

SOL-20

16)

Gibbon(

SOL-20

17)

TimeofDay

5:00

6:00

7:00

8:00

9:00

10:00

11:00

12:00

Siamang

(SOCP)

Siamang

(SOL-20

14)

Siamang

(SOL-20

16)

Siamang

(SOL-20

17)

TimeofDay

24

Table8.Summarystatisticsfortheagilegibbonvocalsurveys.

AgileGibbon-2014

EffectiveListeningArea(km2)

GroupsHeard(n)

p(1) m(days) p(m) Groups/km2 Individuals/km2

ListeningArray1 3.14 7 0.71 4 0.99 2.25 7.41

ListeningArray2 3.14 7 0.71 4 0.99 2.25 7.41

ListeningArray3 3.14 7 0.79 4 1.00 2.23 7.37

Average 3.14 7 0.74 4 0.99 2.24 7.40

AgileGibbon-2016

EffectiveListeningArea(km2)

GroupsHeard(n) p(1) m(days) p(m) Groups/km2 Individuals/km2

ListeningArray1 3.14 7 0.75 4 1.00 2.24 7.39

ListeningArray2 3.14 7 0.82 4 1.00 2.23 7.36

ListeningArray3 3.14 7 0.89 4 1.00 2.23 7.36

Average 3.14 7 0.82 4 1.00 2.23 7.37

AgileGibbon-2017

EffectiveListeningArea(km2)

GroupsHeard(n)

p(1) m(days) p(m) Groups/km2 Individuals/km2

ListeningArray1 3.14 7 0.81 3 0.99 2.24 7.41

ListeningArray2 3.14 7 0.62 3 0.95 2.36 7.78

ListeningArray3 3.14 7 0.86 3 1.00 2.24 7.38

Average 3.14 7 0.76 3 0.98 2.28 7.52

25

Table9.Summarystatisticsforthesiamangvocalsurveys.

Siamang-2014

EffectiveListeningArea(km2)

GroupsHeard(n)

p(1) m(days) p(m) Groups/km2 Individuals/km2

ListeningArray1 3.14 1 0.25 4 0.68 0.47 1.30

ListeningArray2 3.14 2 0.25 4 0.68 0.93 2.61

ListeningArray3 3.14 1 0.50 4 0.94 0.34 0.95

Average 3.14 1 0.33 4 0.77 0.58 1.62

Siamang-2016

EffectiveListeningArea(km2)

GroupsHeard(n) p(1) m(days) p(m) Groups/km2 Individuals/km2

ListeningArray1 3.14 2 0.38 4 0.85 0.75 2.09

ListeningArray2 3.14 2 0.50 4 0.94 0.68 1.90

ListeningArray3 3.14 2 0.50 4 0.94 0.68 1.90

Average 3.14 2 0.46 4 0.91 0.70 1.97

Siamang-2017

EffectiveListeningArea(km2)

GroupsHeard(n)

p(1) m(days) p(m) Groups/km2 Individuals/km2

ListeningArray1 3.14 2 0.33 3 0.70 0.91 2.55

ListeningArray2 3.14 0 0.33 3 0.70 0.00 0.00

ListeningArray3 3.14 1 0.33 3 0.70 0.46 1.28

Average 3.14 1 0.33 3 0.70 0.46 1.28

26

4.1 DiscussionwildlifemonitoringthroughPrimateSurveysandCameraTrapping

Between 2013 and 2016 large-scale development has taken place at the SOLGeothermalArea.Roaddevelopmenthas takenplace to theWJParea through foresthabitatbisectingthe ranges of arboreal primates. This road has created a barrier for these primates, andarborealcrossingsneedtoberestoredforprimatesandotherarborealwildlife,whichmightbe reluctant to cross a road.Daily traffic consisting of cars,motorbikes, trucks havebeenusingthisroad,causingmechanicalnoise;althoughthecurrentlevelofroadusageisunclearthe road still presents a physical barrier. Serious efforts should be undertaken to restorephysicalvegetationandarborealconnectivityforprimatespecieslivinginthearea[gibbons,siamang,mitredleafmonkey,slowloris],asthecurrentwidthoftheroad,withoutarborealcorridors,hassignificantimpactonwildlife,bothdirectlyandindirectly.

Species diversity and relative abundance of mammal species monitored through cameratrapping increased in2017,whencomparedtothecameratrappingefforts in2016.Thesedifferences canbedue to increasedcamera trappingefforts [931 trapnights versus664 in2016],a slightly longercamera trappingperiod,butalsopotentiallydue to less trafficandhumanactivityintheareacomparedto2015-2016whenactiveconstructionwasongoinginthearea.

UsingtheRelativeAbundanceIndex[RAI]canbeusefulformonitoringchangesofthemore'common'speciesintheSOLarea,tolookattrendsofthesespecies’abundanceovertime.Itisimportantthoughtomaintainthesamestudysetup(i.e.numberofcameras,siteswherecamerasaredeployed,wayinwhichcamerasaredeployed,andseasoninwhichsamplingistakingplace)throughouttheentirestudy,inorderforchangesintheRAItoreflectchangesinthefocalspecies’abundance,ratherthanchangesindetectionduetootherfactors.

SeveraloftheCriticallyEndangeredtargetspecies[orangutan,tiger]thatwereencountered[through their sign] in 2013-2014havenownotbeen recorded in 2017.Although in 2014onlyasmallnumberoforangutannests(n=5)wereencounteredintheSOLarea,orangutansareknowntooccurthroughouttheWestBatangToruforestblock(Wichetal.2003,Nateret al. 2012,Wich et al. 2012). The overall orangutan population in theWest Batang Toruforest block has been estimated at some 500-600 individuals (Wich et al. 2016), and isconsideredofhighestconservationimportance,especiallynowthattheTapanuliorangutanhasbecomedescribedasaseparatespecies (Nateretal.2017).SOLprojectstaff thathadworkedintheareasomeyearspriortothecurrentconstructionactivitiesreportedadirectobservationofanorangutanwithoffspringneartheNIL1road(A.Samuel,pers.comm.).

TwoindependentcameratraprecordingsweremadeoftheCriticallyEndangeredpangolin.Anotherspecies,themarbledcat[VU],wasphotographedin2017[andin2014,butnot in2016].

There was a significant increase in the number of Carnivore species recorded in 2017 [8species]comparedto2016whenonly2specieswererecorded.In2014,also8specieswere

4. Discussion

27

recordedalthoughin2017aleopardcatwascaughtoncameratrap,whichhadnotyetbeenrecordedduringpreviousSOLsurveys.

Thesunbear[VU]wascaughtoncameratrapforthefirsttimein2017,althoughrecordedin2016andpriorsurveysthroughsign[clawmarks],aswellasanexcitingdirectobservationofasmallcubatadensite in2016.Largecarnivoressuchasthesunbear,havewelldefinedhome ranges and cannot easily shift the boundaries of their home ranges, as they will'encroach' into the home range of another sun bears, whilst food resources are spatiallylimited[Fredriksson2012].Itispositivethatthesunbearcaughtoncameratrapin2017wasfollowedbyasmallcub.

SomespeciesthatwerethoughttohavemovedoutoftheSOLprojectarea,awayfromthedisturbance in 2015-2016 [heavy machinery, felling of trees with chainsaws in variouslocations, and significant human activity in the area including illegal logging and hunting],mighthavereturnedtotheirrangesnowthathumanactivityhasbeenreduced.Duringthecameratrappingeffortin2017,9independenteventsofhumansanddogswerecaughtoncameratrapcomparedto23 independentevents in2014, indicatingareduction inhumanusage of the area, although in 2016 no people, nor dogswere caught on camera trap. In2017birdpoacherswerecaughtoncameratrap,proudlydisplayingtheircatch.

Oftheoriginal listsoftargetspeciesputforwardintheBAP,knowntooccurintheBatangToruforest,severalspecieshavenotbeenencounteredintheSOLarea.TheseincludeAsiantapir (VU) andbinturong (VU). These speciesmightneedmoreextensive camera trappingefforts.Oneobservationwasmadeofthenocturnalslowloris,Nycticebuscoucang,in2014and althoughnot directly observed recordedduring the 2016 surveys, a potential cameratrap picture was obtained of this species [clear eye shine in the shrubs] but for thesenocturnalspeciesnightspottingsurveyswillbeneeded.

28

Conclusions/RecommendationsWedocumentedahighoccurrenceof a significantnumberof IUCNRed Listed species, aswell aswildlife species protectedunder Indonesian lawoccurring in the SOLproject area.This supports the conclusion that the SOLproject area is an importantpartof theBatangToru Ecosystem, and that despite various development activities over the last couple ofyears,much of themammal assemblage encountered during the baselinemonitoring canstillbefoundintheprojectarea.

Species diversity and relative abundance of mammal species monitored through cameratrappingincreasedin2017,andongoingmonitoringwillbeimportanttoseethelongertermimpactsonwildlife,especiallywhenconsideringthatmanyspeciesthatareresident intheareaarelonglived[gibbonscanliveupto70-80yearsofage].

UsingtheRelativeAbundanceIndex[RAI]hasproventobeusefulformonitoringchangesofthemore 'common' species in theSOLarea,and it canbeused to lookat trendsof thesespecies’ abundance over time. It will be is important though tomaintain the same studysetup(siteswherecamerasaredeployed,wayinwhichcamerasaredeployed,andseasoninwhichsamplingistakingplace)throughouttheentirestudyperiod, inorderforchangesintheRAItoreflectchangesinthefocalspecies’abundance,ratherthanchangesindetectionduetootherfactors.ArborealconnectivityneedstoberestoredalongthenewroadconstructedtoWJP1.Thisroadcutsthroughtherangesofseveralknowngibbongroups,aswellasmitredleafmonkeygroups,andhasbecomeaphysicalbarrierfortheseprimates.Keyareasshouldbereplantedwithfastgrowingindigenoustreespecies[i.e.Ficusspp.,familyMoraceae]sothattherecanbeexchangeandmovementof these species, especially gibbonswhoarenotdesigned tomoveterrestrially.Werecommendrestorationofconnectivityinseverallocationsalongtheroad, starting where this is physically most feasible, aiming to restore connectivity atsectionsoflessthan250metersalongtheroad,whenlookingatthesizeofhomerangesofgibbonsreportedinBatangToru[around50ha].Huntingofwildlife,specificallypoachingofsongbirds, isstillencounterd intheSOLprojectarea, and it is proposed tomake a serious effort to limit/halt free access of people usingproject roads. We recommend to produce personalized passes for these communitymembers and that 'special' treatment is given to these people [i.e. field clothing, safetyoutfits] which could increase their 'pride' in being a close 'relation' of SOL and a goodneighbour[willingtoreportillegalactivities].We also recommend to further develop conservation/hunting agreements focusing onprotected specieswith themain villages/hamlets close to the project area, and in returnprovide support through development of small enterprises that will provide sustainableproteinalternatives(suchasfishponds,chickenfarming,pigfarming).Also, further studies on the potential to improve/enhance the marketing potential ofKemenyan/Haminjon [Styrax benzoin] could be useful, as this non timber forest product

29

[NTFP} is specifically grown in/around the SOL project area. This could become aninteresting,rare,commoditythatSOLandappropriatepartners,couldassistwithimprovingthemarketingof.Toimprovetheco-existenceoflocalcommunitieswithwildlife,itisalsorecommendedthatPTSOLinvestintrialingmethodologiestoreducehuman-wildlifeconflictduetopredationofcropsplantednear the forestedge.Thiswouldbehighlyappreciatedby thecommunities,whilstPTSOLcansetanexampleofpracticalmitigationefforts.OneofthekeyspeciesthathasbeenfoundtocausecroppredationislistedasVulnerableontheIUCNRedList[Macacanemestrina].WeviewthatPTSOL isperfectlyplacedto introduce improvedenvironmentalpracticesbyimplementing the above recommendations to further demonstrate that geothermaldevelopmentcangohandinhandwithconservationofcriticalhabitats.Rigorouslyimposingbestpracticesonitsownworkforceanddisseminationoftheseamongstlocalcommunitieswill enhance the companies local and international reputation, providing a strong casestudy/example for other companies operating in Indonesia, and modify environmentallyharmful practicesby local communities. Furthermore, the company is building a relativelyenvironmentally-friendly energy power plant that will have local impacts on the highlybiodiverseanduniqueBatangToruforests.

30

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Buij R, Singleton I, Krakauer E, van Schaik CP. 2003. Rapid population assessment oforangutandensity.BiologicalConservation,114,103-113.

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Nater A, Arora N, Greminger MP, van Schaik CP, Singleton I, Wich SA, Fredriksson G,Perwitasari-Farajallah D, Pamungkas J, Krützen M. 2012. Marked populationstructure and recent migration in the critically endangered Sumatran orangutan(Pongoabelii).J.Hered.104(1):2–13.doi:10.1093/jhered/ess065.

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i

APPENDIXICameraTrapPhotographsofInterest_SOL2017

éPangolins,CriticallyEndangered,werecaughtoncameratrapontwoseparateevents;êMarbledcat,Vulnerable,wascaughtoncameratraponce;

ii

éMitredleafmonkey,Endangered,wascaughtoncameratrapononeevent;êPigtailedmacaques,Vulnerable,werecommonlycaughtoncameratraps;

iii

éBandedlinsangwasthemostcommoncarnivorecaughtoncameratrap;êTherareMalayweaselMustelanudipeswasoncecaughtoncameratrap;

iv

éYellowthroatedmartenwasoncecaughtoncameratrap;êTheleopardcatwascaughtoncameratrapforthefirsttimeintheSOLarea;

v

éThebarkingdeer,Muntiacusmuntjac,wascommonlycaughtoncameratrap;êWildboarwererelativelyrareintheSOLarea;

vi

éThesambardeer[Vulnerable}wascaughtoncameratrapon21occasions;êArarepictureofasunbearcub[Vulnerable];

vii

éAbirdpoacher;êBirdpoacherwithleafbirds;

I

APPENDIXII

PhotographsofInterest_SOL2017

éFreshserowfecesencounteredalongatransect;êFreshsunbearscatfullofseedsencounteredalongatransect;

II

éFreshdeerfootprintencounteredintheSOLarea;êFreshsunbearclawmarksencounteredalongatransect;

III

éDatacollectionatoneoftheprimatelisteningposts;ê2017YELsurveyteam[Dewi,Eka,Saniah]andlocalSOLassistants;