Not by science alone: why orangutan conservationists must...

Ann. N.Y. Acad. Sci. ISSN 0077-8923

ANNALS OF THE NEW YORK ACADEMY OF SCIENCESIssue: The Year in Ecology and Conservation Biology

Not by science alone: why orangutan conservationistsmust think outside the box

Erik Meijaard,1,2 Serge Wich,3,4 Marc Ancrenaz,5 and Andrew J. Marshall61People and Nature Consulting International, Kerobokan, Bali, Indonesia. 2School of Archaeology and Anthropology,Australian National University, Canberra, Australia. 3Sumatran Orangutan Conservation Program (PanEco-YEL), Medan,Indonesia. 4Anthropological Institute and Museum, University of Zurich, Zurich, Switzerland. 5Kinabatangan Orang-utanConservation Project, Sandakan, Sabah, Malaysia. 6Department of Anthropology, Graduate Group in Ecology and AnimalBehavior Graduate Group, University of California, Davis, Davis, California

Address for correspondence: Erik Meijaard, People and Nature Consulting International, Country Woods House 306, JL WRSupratman, Pondok Ranji-Rengas, Ciputat, Jakarta 15412, Indonesia. [email protected]

Orangutan survival is threatened by habitat loss and illegal killing. Most wild populations will disappear over thenext few decades unless threats are abated. Saving orangutans is ultimately in the hands of the governments andpeople of Indonesia and Malaysia, which need to ensure that habitats of viable orangutan populations are protectedfrom deforestation and well managed to ensure no hunting takes place. Companies working in orangutan habitat alsohave to play a much bigger role in habitat management. Although the major problems and the direct actions requiredto solve them—reducing forest loss and hunting—have been known for decades, orangutan populations continueto decline. Orangutan populations in Sumatra and Borneo have declined by between 2,280 and 5,250 orangutansannually over the past 25 years. As the total current population for the two species is some 60,000 animals in an areaof about 90,000 km2, there is not much time left to make conservation efforts truly effective. Our review discusseswhat has and has not worked in conservation to guide future conservation efforts.

Keywords: deforestation; great apes; hunting; Indonesia; Malaysia; nongovernmental organizations; orangutan; palm

oil; plantations; Pongo abelii; Pongo pygmaeus

Introduction

Orangutans (Pongo spp.) are among the most iconicspecies in wildlife conservation. Popular televisionprograms such as Orangutan Island produced byAnimal Planet and Orangutan Diary by the BritishBroadcasting Corporation (BBC) are testimony tothe public’s interest in these great apes. People’saffinity with orangutans is at least partly basedon the red ape’s behavior, facial expressions, andmannerisms, which can be uncannily human. In-deed, genetic comparisons and morphological, cog-nitive, and behavioral similarities do indicate theclose evolutionary relationship between humansand orangutans.1–3

Despite their similarities, the evolutionary pathsleading to orangutans and to humans diverged some9–13 million years ago.4 After that evolutionary

split, a range of orangutan-like taxa or ponginsevolved, including Gigantopithecus, the largest apethat ever lived. These species primarily occurred inpresent-day Europe and mainland Asia. Of this di-verse lineage, only the genus Pongo survives. In thisrespect, orangutans are not simply two endangeredspecies of great ape, but also represent the sole liv-ing representatives of a diverse clade that includeddozens of distinct pongin species and genera thatoccurred for some 10 million years across Asia andEurope.

Although most of pongin evolution occurred inAsia, the human lineage primarily evolved in Africa.Not until the Pleistocene, when species such asHomo erectus inhabited Asia, did the orangutan andhuman lineages meet, and only some 70,000 yearsago did our own species, H. sapiens, disperse into theorangutan’s realm.5 The co-occurrence of humans

doi: 10.1111/j.1749-6632.2011.06288.xAnn. N.Y. Acad. Sci. xxxx (2011) 1–16 c© 2011 New York Academy of Sciences. 1

Orangutan conservation Meijaard et al.

and orangutans has since then led to the rapid de-cline of the latter, but it is unlikely that humans werethe sole cause of the orangutan’s decline. The dra-matic environmental changes that occurred in Asiafrom the late Miocene to the Pleistocene probablycontributed to the extinction of many of the Asianapes6 and may have substantially reduced orangutanpopulation sizes as well. Broadly speaking, climaticchanges such as increased aridity, more intensemonsoons, and increased frequency and severity ofglacial-inter-glacial cycles caused once widespreadevergreen rainforests, the habitat of orangutans, tobe increasingly restricted to isolated pockets close tothe equator.7,8

The genus Pongo could be found until the LatePleistocene, or some 40,000 years ago, from as farnorth of southern China to the island of Java.9,10 Thepresent habitat of the Sumatran Orangutan (Pongoabelii) and Bornean Orangutan (P. pygmaeus) isprobably less than 5% of the original Pongo dis-tribution range. Even on the two islands of Bor-neo and Sumatra, where the species still occur, theirpopulations had been much reduced by the early19th century when orangutans became first knownto science.11–13 Orangutans have been hunted bypeople at least since the Late Pleistocene,14,15 and arecent study suggests that over-hunting is one of themain reasons for these historic local extinctions ofthe species.12 Orangutan populations have declinedeven more dramatically over the past few decades;both species are considered in danger of becomingextinct in the wild soon.16,17

Orangutan distribution and density

In many high-income countries, orangutans are asymbol for the unsustainable management and con-version of tropical rainforests on Borneo and Suma-tra, especially where this concerns the developmentof oil palm plantations (Elaeis guineensis), whichmany consider a major culprit in the orangutan’s de-cline.18,19 As shown above, the decline of orangutansgoes back much further than the last few decades.The southern half of Sumatra had probably lost allits orangutans by the time Alfred Russel Wallaceand other early explorers and naturalists first de-scribed the orangutan (but see Ref. 13), whereassoutheastern and northwestern Borneo, as well asthe central highlands of the island, were also de-void of the species. Obviously there is more to de-clining orangutan populations than simply oil palm

expansion, suggesting that better analysis is neededof the threats to orangutans and the orangutans’distribution.

One of the main challenges in orangutan conser-vation science has been, and continues to be, thedevelopment of accurate population estimates sothat populations can be monitored. Early estimatesin the 1960s and 1970s varied between a few thou-sand orangutans and 156,000 for all of Borneo20–22

and between 4,500–10,000 for Sumatra.23 New ap-proaches based on absence/presence maps,13 island-wide interview surveys,24 and aerial surveys25–27 ledto more accurate estimates of at least 54,000 individ-uals for Borneo.17 Even this figure should be consid-ered a center point in a wide range of possible realpopulation numbers, because no local densities areknown for many parts of the species’ range (Fig. 1).The population estimate for Sumatra is ca. 6,600,which was recently considered a conservative esti-mate. What we do know is that the area of orangutanhabitats has been in a rapid decline for over 50 yearsnow.11,13,28

After decades of survey work, it is reasonably wellknown where orangutans occur (Fig. 1). In the twoMalaysian States (Sabah, Sarawak) on Borneo, andin Sumatra, this knowledge is relatively accurate.Several areas in Kalimantan have also been surveyedquite well, but large areas of unprotected habitathave only been surveyed in a cursory manner. Theclumped distribution of orangutans13 and high spa-tial variation in density make it impossible to extrap-olate density estimates from one area to another.The variation in orangutan population estimates istherefore more due to an uncertainty about localdensities than to a lack of information about theextent of the two species’ ranges. Many factors havebeen hypothesized to limit orangutan densities, in-cluding the density of fig trees, altitude, forest type,degree of forest degradation, hunting intensity, andpossibly the density of salt licks, or even past and cur-rent disease outbreaks.29–34 Measuring these densi-ties, however, is not easy. Orangutans are difficult tosurvey directly, and accurately estimating densitiesrequires time-consuming surveys of indirect indica-tors such as their sleeping platforms or “nests.”35–37

This is mostly done on foot, but increasingly re-mote approaches such as aerial surveys are used.25,38

These methods have in common that the estimationof the number of orangutans is based on the numberand spatial distribution of their nests. This requires

2 Ann. N.Y. Acad. Sci. xxxx (2011) 1–16 c© 2011 New York Academy of Sciences.

Meijaard et al. Orangutan conservation

Figure 1. Orangutan distribution based on 2003 surveys, with orangutan populations mentioned in the text indicated on themap.

the determination of two factors: the rate at whichorangutans build nests and the rate at which thesenests decay over time. Recent studies have shownconsiderable variation in especially the latter factor,with average nest decay rates varying from 81–602days, depending on factors such as the species oftree in which the nest is built, height of the nest,as well as the species of orangutans.39 Nest surveysrarely determine decay rates locally, and the confi-dence intervals around previous density estimatesare therefore large.40,41 New approaches to nest sur-veys have been considered,42 but none effectivelyovercomes the immense investment of labor andtime that would be needed to accurately determinelocal densities across some 90,000 km2 of dense,relatively inaccessible rainforest. Until new meth-ods emerge, such as the direct detection from theair of orangutans with a thermal scanner, the bestapproach appears to be the combined use of on-the-ground nest surveys with remote nest counts, as well

as the use of interview surveys, which provide bet-ter tools to determine and quantify human threats,such as hunting and agricultural conflict killings.24

Resources made available for conservation are scarceand should be allocated strategically: assessing spa-tial variation in threats and ways to manage theirimpact on major populations is therefore crucialfor the survival of the species.

The context of threats

Recent analysis of forest conversion for oil palmsuggests that at least 10,000 km2, or 5% of thetotal orangutan range, was converted for oil palmbetween 2000 and 2010,43 with the high-densityorangutan populations in the lowlands of easternSabah, a Malaysian state in north Borneo; coastalpeat swamps in Sumatra; and peat swamps in theIndonesian province of Central Kalimantan havingbeen especially affected. Oil palm is indeed a consid-erable threat, but other factors such as unsustainable

Ann. N.Y. Acad. Sci. xxxx (2011) 1–16 c© 2011 New York Academy of Sciences. 3


timber extraction, development of tree plantationsfor pulp and paper, small-scale community agri-culture, mining, and direct orangutan killing areimportant factors in the orangutan’s decline as well.Singling out a particular industry as the main cul-prit in this process ignores the contribution fromothers and is unlikely to lead to lasting solutions.

Wild orangutans rarely require species-specificmanagement (e.g., food provisioning or diseasetreatment), although rope bridges in Kinabatanganto reduce fragmentation effects have been success-fully tested. The majority of conservation interven-tions entail protecting forests and preventing hunt-ing. Despite initial impressions that the species washighly sensitive to forest disturbance,13,33,44 it is be-coming increasingly clear that the species has con-siderable ecological flexibility, allowing it to copereasonably well with such disturbances.45 Somepopulations even use monocultural plantations, al-though it is doubtful whether their survival therecould be long term without access to more natu-ral forest stands.46 What is clear, however, is thatorangutan populations suffer greatly from hunt-ing. In many parts of their range, orangutans arekilled for food, the pet trade, and from conflictsthat inevitably occur as natural forests are con-verted for small and large-scale agriculture. Thisis a major threat as orangutan reproductive ratesare too low to recover from hunting rates >1% fe-males/year.47 Rates of killing appear to far exceedthis: a recent study estimated that annually between750 and 3,500 orangutans are killed in Kaliman-tan.48 Assuming a total population of some 42,500animals in Kalimantan,17 this would imply annualfemale off-take rates between 0.9% and 3.6%. Inaddition to direct mortality, hunting and deforesta-tion have resulted in a steady flow of rescued andconfiscated orangutans into the ten orangutan quar-antine, care, and rehabilitation centers in Indonesiaand Malaysia.49

The different threats to orangutans have re-lated underlying causes. Poor land-use planning al-lows the degradation of known orangutan habitats.Poor forest management results in degraded, fire-prone forests with limited economic value, provid-ing strong commercial and political incentives toconvert these lands to agricultural or silviculturallands. The resulting fragmentation of orangutanhabitats leads to higher human–orangutan conflictand killing rates,17 which go unpunished because of

a lack of law enforcement.17 In addition, too oftenthe quality of protected area management remainsinsufficient to prevent forest loss,50 so even in theseareas orangutans are not safe.

In the past, orangutans had significant culturalvalue among some of the tribes living in or closeto forest areas where orangutans occurred.13 Inthe face of rapid development and modern con-sumerism, however, to many local people on Bor-neo and Sumatra the orangutan has become justanother “monkey.” In interviews with us, many lo-cal people express surprise regarding the amount ofinternational intention for these species while thesepeople themselves are still struggling to survive.51

A 2008 candidate for the governorship of East Kali-mantan (Indonesian Borneo) declared that peopleshould take precedence over orangutans—a politi-cally pragmatic position that is unlikely to changesoon in a country where recent figures indicatedthat 52.4% of the people live on less than US $2per day.51 However, losing wild orangutans wouldhave considerable consequences. Orangutans playimportant ecological roles in forests as ecosystemengineers and seed dispersers52,53 and also providea source of income for some forest communitiesthrough ecotourism.54 More importantly, as oneof the most recognized global conservation icons,their loss would imply that people are not able todevelop life styles that are compatible with the eco-logical needs of our natural world. Losing a greatape from the wild would be a landmark failure. Notonly would we have eradicated one of our closestgenetic relatives, we would also substantially affectthe forests that depend on orangutans, which wouldcause declines of many other taxa and erode the en-vironmental services that forests provide and onwhich many people depend.

Abating the threat to orangutan survival is a polit-ical choice requiring societal approval and coopera-tion for comprehensive solutions that involve strictprotection of key habitats, effective law enforcementagainst harmful illegal activities, and selection ofcompatible land-use practices. In democratic coun-tries, governments will have to justify their choicesin favor of species conservation against the oppor-tunity costs of potentially more profitable land-usepractices. In many cases, that justification is ethicalrather than economic,55 and the orangutans’ futuremay depend on whether people are able to prioritizeethics over economics.



Past population trends

Uncertainties in population estimates have trans-lated into widely ranging estimates of popula-tion trends, including the prediction in 2007 thatorangutans would be virtually extinct in 2012.56 Re-cent data allow us to better approximate annualpopulation declines. Loss of orangutan habitat inSumatra has been estimated at 1–1.5% per year be-tween 1985 and 2001.28 Based on these rates andthe presently remaining area of habitat of 8,641km2 (Ref. 57), the estimated losses over the last25 years range from 2,300 km2 to 4,000 km2. Thesehabitat losses primarily occur in lowland forests,which have the highest densities,31 with a conserva-tive average of 2.5 animals/km2. This would suggestaverage annual losses on Sumatra of 230–400 ani-mals over the last 25 years. Such estimates cannotbe used to predict future declines, because they arebased in forest loss rates in lowland forests, andthese rates will likely be lower in remaining uplandhabitats.

Annual mortality rates of orangutans in Kaliman-tan are estimated at 750–3,500 per year.48 In Sabah,the orangutan population is thought to have de-creased by a minimum of 95% over the past fewcenturies based on analysis of population genetics.11

This is consistent with the decline from a state-wide populations estimate in 1987 of 25,000 ani-mals58 to the presently remaining population sizeof 10,000 individuals,45 suggesting annual losses of1,250 individuals for Sabah only. No estimates areavailable for Sarawak, where a small, relatively well-protected population remains. We estimate thatsome 50–100 animals have been lost annually overthe past 25 years to hunting, animal trade, or habi-tat loss.59,60 This would suggest annual losses forBornean orangutans over the last 25 years between2,050 and 4,850. This range fits the estimated annualhabitat losses of 3,122 km2 up to 2004,28 which, witha density range between 0.5 and 1.5 animals/km2

(Ref. 31), translates into a similar mortality range.

What has been done in orangutanconservation?

Legally, orangutan conservation started in 1924when the species was first protected in what is nowIndonesia.13 New laws primarily involved the settingaside of protected areas on Borneo and Sumatra andincluded prohibition on the then very active zoo

trade in orangutans.61 This prohibition was not en-forced, however, and significant trade in orangutansfor European and American zoos and for biomedicalresearch continued until at least the 1970s.62 Theseissues were brought to the conservation commu-nity’s attention in the Western world by the effortsof Barbara Harrisson,63 and her work signifies thestart of the serious study of orangutans and inter-national attention to their conservation.13

To effectively address threats, orangutan con-servation uses four main strategies: managementof protected orangutan habitat, combating illegaltrade and killing, rehabilitating and reintroducingex-captives into their wild habitat, and developingorangutan-friendly management in nonprotectedareas. These strategies sound relatively straightfor-ward, and, in fact, the principles of orangutan con-servation are simple: minimize unnatural deathsand maximize the availability of suitable habitat.We summarize the main issues for each strategy be-low and explain why things are more complicatedthan they appear.

Management of protected orangutan habitatAbout 25% of all wild orangutans occur in formallyprotected areas.17 This does not necessarily meanthat these populations are safe, because illegal log-ging, mining, and poaching continue in many ofthese protected areas and human–orangutan con-flict occurs on their edges.17,64 Still, these areas pro-vide some level of protection compared to the non-protected parts of their range.65

In Sumatra, orangutans mainly occur in theLeuser Ecosystem, which includes the GunungLeuser National Park, and in the Batang Toru forestblocks (Fig. 1). Conservation efforts for the Leuserarea stem back from the 1930s,66 but the BatangToru population was only recently rediscovered,67,68

and conservation programs therefore began muchmore recently there. Effective management of theLeuser Ecosystem, which includes the national parkand surrounding areas, started in the early 1990sand was boosted by significant European Unionand Indonesian government funding and later byfunding generated after the 2004 tsunami in Suma-tra. We conservatively estimate that a total of US$75 million have been spent on Sumatran orangutanhabitat protection from 1990 to 2011. This is a sub-stantial amount of funding and one might expectthat there are clear measures that would account for



how successful this funding has been for conserva-tion. Unfortunately, this is not as straightforwardas it sounds, and we can only approximate the im-pact of that funding on orangutans. Based on re-cent forest loss estimates,69 it has been estimatedthat between 1985 and 2007, the lowland forestsof Aceh and North Sumatra Provinces, where mostorangutans occurred, have been reduced by 36%and 61%, respectively.57 Orangutan density is high-est in forests on peatlands,31,35 and forest loss inthose habitats was 33% for Aceh and 78% for NorthSumatra. Still, the protected areas of Sumatra doreduce forest loss,65 and the orangutan’s situationwould have been worse without them.70 This is ev-ident in Leuser, even though not all of the LeuserEcosystem was classified as protected during thisperiod. From 1985 to 2007, 11.7% of forest in the25,000 km2 Leuser Ecosystem was converted to otherland uses,57 or up to 20.1% if forest loss in lowlandareas is considered. Most of the dryland forest wasreplaced with agroforestry (31%) and much less byoil palm (19%), but, on peatlands, 79% of the for-est that was lost was replaced by oil palm planta-tions.57 This is bad for orangutans, but again thingswould have been worse without the protected areasand the continued conservation efforts for protectedand nonprotected areas. For Sumatra, it can there-fore be tentatively concluded that protected areasand conservation does work to reduce forests loss,but not to halt it, and that their protected area man-agement and conservation efforts still require muchimprovement.

Kalimantan (Indonesian Borneo) has moreorangutans than any other location. It also hasthe biggest problems in terms of deforestation; for-est degradation and fragmentation; and killing oforangutans for food, pets, and other reasons.17

Some key populations, such as those in the GunungPalung, Tanjung Puting, Sabangau, and Betung Ker-ihun National Parks, are relatively well protected,although forest loss and degradation continue evenin these areas. Outside these protected sites, habi-tat loss and degradation through development ofsmall- and large-scale agricultural and silviculturalplantations is rapidly reducing the areas where vi-able populations can survive. Forest loss in Borneobetween 2000 and 2010 was recently estimated at500,000 ha/year.71 Most of this forest loss has oc-curred in lowland forest on mineral soils and in peatland, both of which are key orangutan habitats. One

protected area, Kutai NP (see Fig. 1), has lost muchof its forest through illegal activities,72 although itstill maintains a significant orangutan populationof over 1,000 animals. Illegal killing of orangutansin Kalimantan appears to impact remaining pop-ulations more than it does in Sumatra73 and theMalaysian side of Borneo.11 This suggests that pro-tected areas, where the potential for law enforcementis higher than outside them, are especially impor-tant in Kalimantan as areas where populations canbe protected from hunting.

Sabah, Malaysian Borneo, has lost more than 40%of its forests over the past century, and the major-ity of its remaining forests are at different stages ofdegradation and regeneration due to past intenselogging activities.74 Today about 50% of the State isstill covered with forest, and 13% of the State pro-tected. Most of Sabah’s lowlands used to be occupiedby orangutans, and it is estimated that between 50and 90% of the original orangutan population waslost over the past 100 years.11 Most orangutan popu-lations are currently found in the eastern side of thestate, where nonhunting Muslim communities pre-dominate. Sixty percent of Sabah’s orangutans oc-cur outside protected areas,25 where they are mostlythreatened by conflicts, hunting, road kills, lack offood resources, intense population fragmentation,and increased sensitivity of forest blocks to natu-ral and human-made catastrophes. Still, forest lossis slowing in Sabah and protected areas are rela-tively well managed, although unfortunately most ofthem were established in marginal orangutan habi-tat, such as the highland forests of Crocker Rangeand Kinabalu National Parks (Fig. 1). The hopefor Sabah is that relatively low hunting levels andstabilizing land use will allow the development ofa network of interconnected, well-protected areasthat would allow an orangutan population to sur-vive in a mixed landscape of plantations, timberconcessions, and protected areas. In addition, theState is trying to identify mechanisms to secure thelong-term sustainable management of some unpro-tected forests through the development of mech-anisms such as biodiversity credits in the MaluaBiobank project and forest carbon initiatives. Inaddition, sustainably managed forests, such as theDeramakot timber concession, which is certified bythe Forest Stewardship Council (FSC), are very im-portant orangutan sites that appear to sustain andmaintain viable orangutan populations. The State



aims to FSC certify all its commercial forests before2020.

Finally, in Sarawak, Malaysian Borneo, most re-maining orangutans occur in two protected ar-eas, Lanjak Entimau and Batang Ai, for which apopulation of 1,143–1,761 orangutans has beenestimated.17 Little information exists about themanagement of these populations, because conser-vation activities by nongovernmental organizations(NGOs) and research are not encouraged in theState.

Law enforcementOrangutans are fully protected in both Malaysia andIndonesia. Large fines or jail sentences are mandatedfor those who kill, trade, or illegally keep orangutansor illegally clear their protected habitats. Hunting oforangutans for food, the pet trade, and to avoid cropdamage is rampant in Kalimantan,24 and huntingpressure is the strongest determinant of orangutandensity in East Kalimantan Province.30 Many illegalactivities related to orangutans have been reportedin the media, but only in 2011 did the first two pros-ecutions occur in West Kalimantan, Indonesia forpeople caught trading orangutans.75 This reportedlyresulted in prison sentences of eight months and oneand a half years. Malaysia is somewhat stricter in theenforcement of its wildlife laws, but there offendersare rarely prosecuted.

With illegal logging and orangutan killing beingamong the major threats, improved law enforce-ment, together with effective public campaigns, arekey strategies. Unfortunately, commitment from thegovernment to enforce laws is generally lacking, andfew resources have been made available to makelaw enforcement more effective.73,76 In addition, feworangutan conservation organizations focus on in-creasing law enforcement. This might be because itinvolves the risk of being considered in oppositionof people that live alongside the orangutan. In ad-dition, foreign private or government donors shyaway from funding law enforcement because of thepotential risk of being seen as meddling in inter-nal affairs of another country. Interestingly, someof the best examples of law enforcement are seenamong local communities themselves, such as theHonorary Wildlife Warden scheme in Kinabatan-gan, Sabah, or the Wehea forest in East Kalimantan(Fig. 1), which is managed and patrolled primarilyby local community stakeholders.

With regard to law enforcement, most conser-vation organizations focus on the role of com-panies in the destruction of orangutan habitats,especially when this is illegal or semilegal. Thesesemilegal cases involve the many gray areas in thelegislation related to orangutan conservation. Im-portantly, among these is the fact that althoughorangutans are protected this does not mean thatit is illegal to destroy their habitat, even thoughlarge-scale forest clearing clearly leads to the death oforangutans. For orangutan conservation to functionbetter, governments need to clarify what it means tobe a protected species and translate this into mean-ingful and operational legislation.

Orangutan rehabilitation, reintroduction,and translocationOrangutan rehabilitation centers were first createdin Malaysia in the 1960s, and the earliest effortsin Indonesia date to the 1970s. They were initiallyset up as law enforcement units in response to thegrowing number of captive animals seized by law en-forcement authorities, with those in Malaysia run bythe government and the Indonesian ones by NGO.These centers have been increasingly presented byNGOs and media as the frontline for orangutanconservation in Southeast Asia.77 Between 1964 and2008, Indonesian and Malaysian orangutan rehabil-itation projects have taken in at least 3,320 animalsand released around 1,250,49 or about one thirdof the original intake. The intake number is cer-tainly an underestimate, however, because of thehigh number of mortalities, especially among veryyoung orangutans. Presently, an estimated 2,000orangutans live in orangutan care centers waiting tobe released back into forest habitats. Past efforts torelease orangutans have had low success rates, withfew orangutans reportedly surviving in one locationwhere over 400 orangutans were released.78 Mor-tality rates of reintroduced orangutans vary from20% to 80%.49 Assuming that survival rates in theseunstudied populations are an average 50%,49 ca.625 orangutans have been successfully reintroducedover a 45-year period.

Translocation involves the transfer of orangutansfrom one area, often a forest on the verge of beingcut down or an area where orangutans cause con-flicts, to another, safer one. There are few publishedfigures on the number of orangutans that have beentranslocated over the years (but see Ref. 79), nor have



follow-up studies been conducted regarding the fateof translocated animals. Similar to reintroductions,the challenge for translocations is to find areas ofprotected, good habitat into which orangutans canbe released. Most of these locations are very remote,making it costly to transport orangutans there andto provide postrelease monitoring and care.

Despite the relatively low success rates, conser-vation investment in orangutan rehabilitation andreintroduction remains high. The cost of feed-ing and caring for an orangutan can be estimatedfrom the operational costs of US $3.2 million forabout 1,200 orangutans reported by one programin 2007,80 suggesting annual management cost perorangutan of US $2,670. As this does not take intoconsideration acquisition and maintenance costs ofland, buildings, and vehicles, a minimum cost ofUS $3,000 per orangutan per year is more likely. InKalimantan, where many orangutans are released invery remote sites, the one-off logistical cost of re-leasing one orangutan into the wild, not includingpostrelease monitoring, is about US $5,000 per an-imal (M. Desillets, personal communication). With63–97% of animals arriving in rehabilitation cen-ters being younger than the minimum release age ofseven years,49 mean time from admission and releaseis likely to exceed three years. A minimum averagecost of US $14,000 per animal from rescue to re-lease is realistic. These estimates consider only thoseanimals that are successfully rehabilitated and reachthe reintroduction stage. A significant number oforangutans cannot be reintroduced due to diseasesor physical impairments and are kept in captivityfor life, requiring long-term funding without directconservation benefits.

Developing orangutan-friendly managementin nonprotected areasWith most orangutans occurring outside protectedareas and with minimal chances that much morehabitat will be formally protected, the inevitableconclusion is that the majority of orangutans willhave to be managed in forests that are also used forother purposes. There is hope that well-managedforests, and even plantations, can provide habitat fororangutans, although much more research is neededhere to examine which factors determine orangutansurvival in multifunctional landscapes.45,46,81 Forsuch multifunctional landscapes to provide viablehabitat for orangutans as well as people, a signif-

icant shift in perspective is needed among conser-vation groups, governments, forest managers, andlocal communities.24,82 It will require that we stopseeing conservation in black and white terms of un-protected and protected or natural and unnatural.83

We need to acknowledge that the orangutans’ fu-ture will depend on their survival in human-madelandscapes and not pristine habitats only.

There is a hugely important role for publicawareness campaigns and educational programs topromote peaceful coexistence between people andorangutans. There is also a need to develop clearermanagement guidelines that prescribe how forestsand plantations can best be managed to maxi-mize the survival chances of orangutans (and otherwildlife) while minimizing the costs to managers.Governments need to assist this process by makingsuch management guidelines mandatory or to pro-vide financial incentives, such as tax breaks, to off-set the extra costs of wildlife-friendly management.Western or local markets could potentially play arole as well by paying higher prices for productsharvested from orangutan-friendly sites or refusingto buy those from badly managed ones. This wouldrequire some transparent auditing process, however,and the costs of doing this are often higher than thepotential gains from premium prices.84

The role of research in orangutanconservation

Researchers like orangutans. A search in a scien-tific literature database (Current Contents) of key-words “Orangutan” and “Pongo” revealed about thesame number of search hits (n = 249) as similarsearches for “Tiger” and “Panthera” (n = 284), “Ele-phant” and Elephas” (n = 320), and “Panda” and“Ailuropoda” (n = 226), all iconic conservationspecies. Orangutan research covers many fields in-cluding evolutionary genetics, ecology, behavior,disease and veterinary medicine, and field surveymethodologies. Many orangutan studies justify theirresearch by referring to the species’ endangered sta-tus, but how relevant are they actually for orangutanconservation?

Although research has provided important dataon behavioral ecology, habitat needs, and the ge-netic structure of populations, which are rele-vant for orangutan conservation, most research onorangutans provides little specific information orinsights that can be directly applied to conservation



planning and management.85,86 For example, eventhough it has been suspected for a long time that il-legal killing of orangutans was a major factor in theirconservation,13,30 the first comprehensive, quantita-tive data set on this problem was not developed until2009 and only exists for Kalimantan.24 Similarly, weare still unable to provide accurate population es-timates for the orangutans in the Indonesian partof Borneo, because coordinated research and surveyefforts have not been undertaken. Many importantpractical questions remain unanswered, includingthe impact of roads and plantations on orangutandispersal; the nature, causes, and possible solu-tions of human–orangutan conflicts; effectivenessand efficiency (cost–benefits) of different conserva-tion strategies; orangutan survival in agroforestryor plantation landscapes; or the value of reforesta-tion and corridor development for meta-populationdynamics. This is not to say that orangutan re-searchers do not contribute to orangutan conser-vation. Often, simply by virtue of their presence,researchers keep hunters and illegal loggers out ofareas that would otherwise be unprotected or evenplay an active role in the development and man-agement of protected areas. Still, this concerns spe-cific, research-intense areas only and not the broaderlandscape level needed for successful orangutanconservation.

A specific shortcoming of orangutan conserva-tion is that it receives limited input from local sci-entists. Many Malaysian and Indonesian scientistshave been trained in conservation science or specif-ically worked on orangutans, but their contributionto further orangutan conservation science remainstoo limited.87 A search in the scientific literaturedatabases Current Contents and Web of Science forkeywords “orangutan/orang-utan” and “conserva-tion” indicated that between 1993 and the presentabout 1% of these publications were written byMalaysian or Indonesian scientists, as indicated bytheir position as first author.87 The scientific litera-ture on orangutan conservation is dominated by En-glish, American, French, Dutch, Australian, Singa-porean, and Japanese researchers. The consequenceof this is that the role of indigenous researchersin translating research findings into locally rele-vant policy recommendations or media communi-cations is underused. Successful orangutan conser-vation will require societal change in Malaysia and

Indonesia, and local scientists could play a muchmore pronounced role in facilitating that change.It is beyond the scope of the present publicationto identify the underlying causes of this relativelyweak role of indigenous conservation science, butexamples from other developing countries indicatethat level of economic development may not be akey factor. For example, a similar literature searchfor “Brazil,” “jaguar,” and “conservation” indicatedthat about 50% of the publications were written byBrazilian or Argentinean researchers; about 75% ofthe publications on “India,” “tiger,” and “conserva-tion” had a first author of Indian nationality; andabout 78% of the publication on “China,” “panda,”and “conservation” were first-authored by Chinesescientists. There is an urgent need to increase localscientific capacity and active engagement of thesescientists in Indonesia and Malaysia, which shouldeventually result in better societal comprehension ofthe different aspects of orangutan conservation, im-proved political uptake of key environmental ideas,and more media attention to these issues supportedby local rather than international conservationfigureheads.

Finally, conservation involves the manipula-tion of human–nature interactions with a viewtowards stabilizing ecological and environmentalprocesses and trends. How these social and eco-logical systems interact, however, remains poorlyunderstood.88,89 The lack of progress is largely dueto the traditional separation of ecological and so-cial sciences.90–92 Orangutan researchers who wantto justify their work through its supposed posi-tive impacts on orangutan conservation need todo a better job at identifying relevant questionsfor improving orangutan conservation. This mayrequire a type of science different from the ecol-ogy and behavior focus that is normally associatedwith great ape research. Useful orangutan conserva-tion research needs to delve into disciplines such aseconomics, political studies, law, sociology, forestry,and agricultural studies—that is, a much more mul-tidisciplinary approach than traditional orangutanscience. For conservation science to be useful, theconservation benefits should not be a serendipi-tous afterthought, but rather a clearly stated pri-mary objective: what research do we need to con-duct to achieve significant orangutan conservationoutcomes?86,93



What could the orangutan’s future looklike?

The orangutan’s extinction is considered to be im-minent by some,56 while others have suggested thatthe species has good habitat strongholds and alsopossesses more ecological flexibility to cope withchanging environmental conditions than previouslythought.26,28,45,46,81 Despite that apparent flexibil-ity, however, two factors work against the species:their inherently low reproductive rates and the on-going high mortality rates caused by conflict killings,hunting, and habitat destruction. These factors, inaddition to the continuing habitat conversion, makeit difficult to predict whether any viable populationswill remain a few decades from now. Key factors thatwill determine the outcome of this are the effective-ness of law enforcement that is needed to reduceorangutan killings and increased awareness leadingto cultural change regarding land management andthe treatment of protected species. The value of thelatter is obvious in areas such as the Kinabatan-gan region in Malaysian Sabah, where traditionallypeople do not hunt orangutans and where despitesevere fragmentation and degradation of originalhabitats, high densities of orangutans remain.11,26

The situation in this part of Malaysia indicates thatorangutans and people can potentially coexist andthat orangutan populations can be sustained if largeenough forest areas are connected to permit disper-sal. This will, however, require significant changes inthe attitude of politicians; land-use planners; large-land holders such as plantations, timber operations,and mining companies; and the millions of ruralpeople that share ever-diminishing forest resourceswith the remaining orangutan populations.

Population viability analyses indicate that, inmoderate quality habitats, orangutan populationsstarting at 500 individuals can maintain sufficientsize and genetic diversity to persist for hundredsof years.47 At least on Borneo, orangutan popula-tion densities rarely exceed two individuals/km2,31

meaning that at least 250 km2 is required to pro-vide a reasonable chance of long-term persistence.This assumes that no other factors such as huntingor disease cause unnatural deaths. There is moreto this story though, as is becoming clear in Kina-batangan, where populations have shown slow butsteady decreases that might be caused by unflangedmales leaving their natal population to look for other

areas in which to settle. To facilitate this interpop-ulation dispersal, habitat connectivity between ma-jor orangutan populations should be maintained orreestablished whenever possible.

We expect that the future of orangutans will verymuch depend on the long-term security of large,strictly protected areas where illegal logging andhunting are effectively controlled and orangutanpopulations are large enough to cope with po-tential catastrophic events such as fires or diseaseoutbreaks. In addition, these areas need to con-tain ecological gradients that allow orangutans andtheir key resource requirements to adapt to moregradual changes, such as those brought about byclimate change. Ideally, the core-protected partsof the orangutan range should remain connectedwith other forest areas. These would not necessar-ily have to be totally protected, but could also beused for commercial extraction purposes, at leastfor the orangutan subspecies with the ecologicalresilience to survive in such used forests.45 Suchan ecological network of protected areas, intercon-nected via forested watersheds, could in turn bebuffered by low-intensity plantations, such as thoseused for pulp and paper and possibly also large-scale oil palm. This would then border on the highintensity-use areas where most people live, whereinfrastructure such as roads is concentrated, andwhere small-scale agriculture and silviculture areconcentrated. Such a landscape would have ampleroom for economic development while optimizingthe use of ecosystem services such as prevention ofsoil erosion, regulation of hydrology, and storage ofcarbon.57

The above idealized picture of ecologically con-nected networks remains very far removed from thepresent paradigm of rapid economic developmentthrough exploitation of natural resources and con-version of forest landscapes to nonforest ones with-out large-scale future land-use planning. The type ofplanning needed to retain or regain ecological con-nectivity on Borneo and Sumatra urgently requiresthat political decision makers recognize the value ofsuch landscapes for the long-term socioeconomicsof these lands. For this, environmental values (eco-nomic, ethical, and legal) need to be consideredmuch more specifically in the land-use planningprocess. Island-wide planning frameworks needto be created that show different tradeoff scenar-ios between short-term economic gains from land



development and longer-term benefits from main-taining sustainably managed forest environments.Based on this, governments can make an informedchoice on how they envisage the long-term devel-opment of Borneo and Sumatra.

The way forward in orangutanconservation

Despite five decades of conservation attention forthe orangutan, there has been frustratingly littleprogress. Even though we do not know how manyorangutans existed some 50 years ago, we do knowthat every year large areas of orangutan habitatare degraded or lost at a rate of some 4,000 km2

per year in Borneo and Sumatra.28 This suggeststhat unless deforestation and hunting trends im-prove significantly, most wild orangutans will per-ish by 2025 and some important populations suchas those in Tripa, Sumatra could disappear as earlyas 2015/16.57 Even in protected areas, forests arenot safe from illegal logging,50,94,95 and we are along way away from the goal of the Indonesian gov-ernment to stabilize all wild orangutan populationsin Indonesia by 2017.96 The obvious conclusion isthat, despite local progress and conservation suc-cess, the orangutan conservation movement has notdone enough to turn the tide of the orangutan’sfate.

This is not to say there has been no success. Manyprotected and relatively well managed areas wouldnot exist or would have lost most their forest withoutthe major lobbying and management efforts of peo-ple or groups highly committed to the orangutanssurvival: Kinabatangan, the Leuser Ecosystem,Gunung Palung, Tanjung Puting, and Sabangau aregood examples. Other areas, such as the Wehea com-munity forest and the FSC-certified Deramakot tim-ber concession show that forests do not have tobe legally protected for orangutans to have a safehome. We should learn from these successes andreplicate them where possible. At the same time, weshould not lose sight of the fact that for most wildorangutans living outside these relatively protectedareas (comprising some 75% of the total popula-tion), the immediate future remains grim if over-exploitation of forests and conversion of naturalforests to planted or nonforest continues. Minimiz-ing losses among these populations requires a majorstrategic change in how orangutan conservation isdone.

The two most important groups involved in con-servation are the governments of Indonesia andMalaysia and a range of local and internationalNGOs. Governments are responsible for policy de-velopment, land-use planning, law enforcement,and conservation management in protected areas. Itis obvious that, despite orangutans being fully pro-tected, existing legislation and policy do not pro-vide sufficient protection for them. Governmentsneed to develop much more holistic policies that notonly target economic progress, but also balance thatprogress with ecological and environmental sustain-ability. The Indonesian government has shown itscommitment to this in its national orangutan ac-tion plan and its low carbon growth objectives,97

but this general commitment needs to be trans-lated into new land-use plans and new policies onland use that integrate protected area managementwith broader landscape-level management. Socio-ecological sustainability should become a generalpolicy principle if orangutans outside protected ar-eas are to survive. Governments also need to recog-nize the spatial heterogeneity of threats and designarea-specific plans to reduce these threats. This linksto the law enforcement and protected area manage-ment roles of the government, neither of which isup to standards at the moment. Governments needto seriously consider how they can improve theireffectiveness in both these roles. Strengthening lawenforcement needs to happen by ensuring that thosethat break the law are actually caught and prose-cuted. This will require training of police, judges,and conservation authorities; effectively combatingcorruption in government offices; and also ensuringthat the public understands why these laws are nowtaken seriously. The latter requires effective cam-paigns informing the public. This is needed becausea recent study suggested that 27% of the peoplein Kalimantan did not know that orangutans arelegally protected.48 The Indonesian government hasvoiced the idea to privatize some of these functions,specifically aiming to outsource the management ofnational parks to the private sector.98 How protectedarea management could be financially attractive tothe private sector is unclear, however, and priva-tizing conservation management is unlikely to be apanacea.

Many NGOs are involved in orangutan conser-vation. These range from local activists groups thatuse public protests and graphic images of orangutan



suffering to engender public awareness and compas-sion to big global conservation organizations. Whatmany of these organizations have in common is thatthey work by themselves on their own projects andrarely coordinate their activities with those of othergroups. This lack of cooperation and absence ofcoherent joint planning is a significant weakness ofthe orangutan conservation community.99 Attemptshave been made to improve this, and the Indonesianorangutan conservation action plan of 2007 was agood example of different NGOs working togetherto effectively push for new legislation. This hap-pens too rarely though, leaving much conservationaction uncoordinated and not adding to an over-all conservation framework. This is not to say thatall conservation activities should be coordinated—great conservation gains have been made by peopleor organizations working on their own. The key,however, is to collaborate and team up with otherswhen broader issues are at stake, such as the devel-opment of new legislation or the implementationof country-level management plans for orangutans,which requires coherent and generally supportedlobbying effort to influence government.

Companies play an increasingly important rolein orangutan conservation. Many of them have anumber of key characteristics that would permitthem to effectively address conservation goals, at-tributes, which are not always present in govern-mental and NGOs. Companies generally have well-trained staff and strong operational procedures fortheir management—slotting in orangutan-specificmanagement should be relatively easy. Companiesalso tend to have significant financial resources attheir disposal. The key question to them is whetherthe cost of investing in good environmental andspecies management is offset by the benefits. Thosebenefits can be a direct financial one (e.g., whenmarkets pay premium prices for products from well-managed companies), but more often they are asso-ciated with having a green image, which in today’sworld can be a significant indirect financial bene-fit for companies. With most of the land outsidethe protected areas being managed by companies,there are obvious needs to involve this sector morein orangutan habitat management. Whether or notsuch companies are interested will depend greatlyon regulatory requirements, the companies’ sensi-tivity to public opinion, and the potential financialgains.

The most important and least engaged sectorare the estimated 36.5 million people in Borneoand northern Sumatra that live alongside the ap-proximately 60,000 orangutans (i.e., 605 people perorangutan). The day-to-day needs of these peopleand their aspirations in life play a hugely importantrole in what will happen to remaining orangutanhabitats. The extent to which these people are will-ing to live next to orangutans might be the decidingfactor for the great ape’s future outside protectedareas.24,81,82 Encouraging these people to supportthe principles of environmental conservation andsustainable development and be actively responsi-ble for the management of their resources is there-fore a crucial requirement for successful orangutanconservation.54 Conservation groups need to thinkreally hard about how this issue can be more effec-tively addressed. It would likely include the contin-uation of various small-scale education programs,but it would also require broader, regional, or na-tional level campaigns with messages that do notjust call for the protection of orangutans but chal-lenge people to think of conservation in the contextof their own lives. Linking conservation to other as-pects of people’s lives such as more efficient agricul-tural methods or health programs100 might be moreeffective than simply telling people that they cannotharm orangutans. After all, people are sometimesconfused. Why does the West pay so much attentionto the protection of orangutans (i.e., “people of theforest” in the Malay language), while local commu-nities consider themselves to be the people of the for-est?51 Conservation needs to make sure that doublestandards and different viewpoints about conserva-tion are clarified and addressed where possible.58

Finally, who is going to pay for conservation?Orangutan conservation costs money. At least aslong as markets are not paying for environmentalservices provided by forests, exploiting these forestsor replacing them with more productive uses isalways going to generate more revenue than con-serving them. Some of these opportunity costs canbe offset by legislation or ethics—we are legallyobliged to protect these forests, or we feel it is theright thing to do—but in most situations the pro-tection or sustainable management of orangutanhabitats will have to be paid for. Carbon marketsmay provide some of these financial means requiredfor this,57,101 while other sources of income couldbe from tourism, payments for water, and other



forest-related economic activities. Companies couldalso fund a significant part of the total financialrequirements by implementing orangutan-friendlymanagement on their land. Ultimately, however, themain responsibility for orangutan conservation lieswith the Indonesian and Malaysian governments,which need to develop the financial and economictools that allow their countries to continue eco-nomic development, but not at the expense of thefew remaining orangutan habitats.

Acknowledgments

We thank the Arcus Foundation for their support.We thank Riswan and Graham Usher for their helpin making the map and two anonymous reviewersfor providing feedback about our manuscript.

Conflicts of interest

The authors declare no conflicts of interest.

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