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PUMS99:1 UNIVERSITI MALAYSIA SABAH

BORANG PENGESAHAN STATUS TESIS@

J'UDUL: THE DISTRIBUTION AND ABU.NDANCE. OF PR080J'CIS

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THE DISTRIBUTION AND ABUNDANCE OF PROBOSCIS MONKEY

(Nasalis larvatus) IN GARAMA, KLIAS PENINSULA

DEEPAL~PANCHANATHAN

TIllS THESIS IS SUBMITTED AS FULFILMENT OF THE REQUIREMENT FOR

THE DEGREE OF SCIENCE

CONSERVATION BIOLOGY

SCHOOL OF SCIENCE AND TECHNOLOGY

UNIVERSITY MALAYSIA SABAH

March 2005

11

DECLARATION

I hereby declare that the thesis is based on my original work except for the quotations and

citations which I have duly acknowledged.

31 March 2005

ALUXMI P ANCHANATHAN HS2002-3536

11I

CERTIFIED BY

Signature

1. SUPERVISOR

(DR. HENRY BERNARD)

2. EXAMINER 1

(PROF MADYA DR. ABDUL HAMID AHMAD)

3. EXAMINER 2

(MADAM ANNA WONG)

4. DEAN

(pROF MADYA DR.AMRAN AHMED)

IV

ACKNOWLEDGEMENT

First and foremost, I would like to extend my heartfelt gratitude to my supervisor, Dr

Henry Bernard for his guidance and help throughout the completion of this thesis. His

patience and time spent following the progress of this thesis from the very beginning is

very much appreciated. His experience and knowledge in the related field is very much

respected and admired.

I would also like to convey my thank you to my course mate, Miss Y oges who

was there with me throughout the sampling sessions. Not forgetting my friends, Miss

Kavin Mullai and Miss Vickneswary, who assisted us during the second sampling session.

I would also like to thank my friends Miss Kayalvizhi, Miss Deepashini, Miss Kael ViIi

and Miss J asvin for their kind support.

Another important person I would like thank is Miss Siti Sarah, a post-graduate

student in the Institute of Tropical Biology and Conservation for playing the role of an

elder sis during the sampling sessions. Her help and guidance will not be forgotten. I

would also like to extend my gratitude to Mr Sikula, who provided help with the maps of

the Garama area. Not forgetting Encik Awang Mahsis and his family, who took care of

my welfare during my sampling sessions in Garama.

I would like to thank my roommate, Miss Norizan who provided great help in

times of misfortune which struck me during the peak of completing this thesis.

Last but not least, I would like to thank my family for providing moral support

and help by looking for articles and additional information on the species.

v

ABSTRACT

A study on the distribution and abundance of Proboscis Monkey (Nasalis larvatus) was

undertaken at Garama, central part of Klias Peninsula on the west coast of Sabah. Two

sampling sessions were conducted for this study. For the fust sampling session, a five day

survey was carried out from 9 to 13 August 2004 and the second sampling session was

conducted from 17 to 20 December 2004. Census survey along watercourses was done

from a boat and total distance of 33.3 km along 5 main rivers in Garama was surveyed.

The overall estimated population density of N. larvatus in Garama was 0.84 groups/km2

or 6.33 individualslkm2• Nasalis larvatus populations were not uniformly distributed in

Garama. Mangrove forests and peat swamp forests were the major habitat types where

N larvatus was observed. The animal was not observed in village areas and agricultural

lands. The survival of N larvatus populations in Garama was affected by factors related

to human activity. illegal hunting, habitat destruction and fragmentation and unmonitored

wildlife based tourism were among the threats faced by N larvatus in Garama.

Recommendations related to N. larvatus population conservation and management

includes the establishment of protected areas in Garama, public education on conservation

issues of this species, monitoring of wildlife based tourism in Garama and frequent

studies on the population density of this anima1.

VI

ABSTRAK

Satu kajian untuk menentukan taburan dan kelimpahan Monyet Belanda (Nasalis larvatus)

telah dijalankan di Garama yang terletak di bahagian Pantai Barat Daya Negeri Sabah.

Dua sesi persampelan telah dijalankan dalam kajian ini. Bagi sesi persampelan pertama,

tinjauan selama lima hari telah dibuat dari 9 hingga 13 Ogos 2004 manakala sesi

persampelan kedua telah dijalankan dari 17 hingga 20 Disember 2004. Tinjauan

dijalankan dengan menggunakan bot merentasi sungai-sungai di kawasan kajian. Jumlah

jarak yang dilalui ialah 33.3 Ian merentasi 5 sungai utama di Garama. Anggaran

kepadatan keseluruhan N. larvatus yang diperoleh daripada kajian ini 0.84 kumpulan/km2

atau 6.33 individulkm2• Populasi Nasalis larvatus tidak tertabur secara sekata di Garama.

N. larvatus paling kerap ditemui di hutan paya bakau dan hutan pinggir sungai. Monyet

ini tidak dijumpai di kawasan kampung dan kawasan perladangan. Kemandirian populasi

N. larvatus di Garama dipengaruhi oleh faktor-faktor berkaitan dengan aktiviti manusia.

Pemburuan tak terkawal, pemusnahan dan fragmentasi habitat dan pelancongan

berkonsepkan hidupan liar yang tidak terkawal merupakan antara ancaman kepada

populasi N. larvatus di Garama. Cadangan berkaitan dengan pemuliharaan dan

pengurusan populasi N. larvatus termasuk pengiktirafan kawasan perlindungan di Garama,

menyedarkan orang awam tentang isu-isu pemuliharaan spesis ini, pemonitoran aktiviti

pelancongan berkonsepkan hidupan liar and memperbanyakkan kajian yang melibatkan

density populasi monyet ini.

CONTENTS

DECLARATION

APPRO V AL OF EXAMINERS

ACKNOWLEDGEMENT

ABSTRACT

ABSTRAK.

LIST OF CONTENTS

LIST OF TABLES

LIST OF FIGURES

LIST OF SYMBOLS

CHAPTER! INTRODUCTION

1.1 Introduction 1.2 Objectives of study

CHAPTER 2 LITERATURE REVIEW

2.1 Systematic Classification of N larvatus 2.2 Morphological Features 2.3 Distribution and Habitat 2.4 Social Organization 2.5 Daily Activity Patterns 2.6 Feeding Ecology 2.7 Conservation Status

Page

11

III

IV

V

VI

Vll

IX

X

Xl

1 3

4 5 6 9 9 10 11

Vll

CHAPTER 3

CHAPTER 4

CHAPTERS

CHAPTER 6

3.1 3.1.1 3.1.2 3.2 3.3

4.1 4.2 4.3 4.4 4.5 4.6

5.1 5.2 5.3

REFERENCES

APPENDIX

METHODOLOGY

Study Area Census Survey Mapping Distribution Estimating Population Density Statistical Analysis

RESULTS

Weather Conditions during Samplings Sightings of N. larvatus Groups Habitat Selection Types of N. larvatus Group Sighted Distribution of N. larvatus in Garama Abundance of N. larvatus in Garama

DISCUSSION

Distribution Abundance Conservation Management and Recommendations

CONCLUSION

14 19 21 21 22

23 24 25 26 27 31

34 35 37

41

43

47

Vlll

Table number

4.1

4.2

4.3

4.4

LIST OF TABLES

The length of rivers surveyed during the study of N larvatus in Garama

Mean sighting distance and its standard deviation for the first and second sampling sessions.

Population size and population density of N larvatus along the rivers surveyed for the first sampling session.

Population size and population density of N larvatus along the rivers surveyed for the second sampling seSSIon.

IX

Page

28

32

32

33

x

LIST OF FIGURES

Figure Number Page

2.1 Recent records of N larvatus in Borneo 7

3.1 Klias Peninsula in the west coast of Sabah (inset) and 15 The location of Garama study area (A)

3.2 The location of the rivers surveyed for the distribution 18 and abundance of N larvatus in Garama

4.1 Frequency of sightings of N larvatus groups in 24 three different weather conditions.

4.2 Number of N larvatus groups sighted in Garama 25 during the first and second sampling session at different hours of day.

4.3 Major habitat types of N larvatus groups 26

4.4 Types of N larvatus group observed during the 27 first and second sampling

4.5.1 Distribution of N larvatus in Garama during the 29 first sampling session

4.5.2 Distribution of N larvatus in Garama during the 30 second sampling session

Xl

LIST OF SYMBOLS

% percent

lan2 kilometer square

m metre

mm milimetre

sp. speCIes

kg kilogramme

cm centimetre

CHAPTER 1

INTRODUCTION

1.1 Introduction

Borneo Island is home to many unique species of flora and fauna. Sabah, which occupies

the northern part of Borneo Island, is rich in ten primate species, including species that

are considered endangered and vulnerable to extinction such as the Orang Utan (Pongo

pygmaeus) and Proboscis Monkey (Nasalis larvatus) (Cowlishaw & Dunbar, 2000).

In the tropical rain forest ecosystems, many primate species perform important

ecological functions. Pongo pygmaeus, for example is a seed disperser in its natural

habitat (Galdikas, 1982). Nasalis larvatus plays an important role in maintaining

vegetation diversity (Yeager, 1989). By feeding on young leaves and seeds of the most

dominant tree species in its habitat, N. larvatus gives a constraint to the reproductive

success of the dominant tree species, thereby allowing other less dominant or rare tree

species to grow (Yeager, 1989).

2

Many large animals are significant tourist icons. Nasalis larvatus is a popular

tourist attraction because this species is highly visible and spectacular in appearance.

Nasalis larvatus is probably the only species of primate with very long, pendulous nose

that overhangs the mouth (Bennett & Gombek, 1993). This species is also an important

national heritage as it is endemic to Borneo.

Studies on the ecology and behaviour of Nasalis larvatus were carried out

extensively at few places only, examples at the Samunsam Wildlife Sanctuary in Sarawak

(Bennett, 1986), Tanjung Puting National Park in Kalimantan Tengah, Indonesia (Yeager

& Blondal, 1990) and Lower Kinabatangan in Sabah (Boomatana, 2002). An extensive

survey on the general distribution pattern of this species was undertaken by Meijaard &

Nijman (2000) throughout Borneo. In addition, several short term studies have also been

conducted by Bernard (1997, 2005) in Klias Peninsula, Sabah. Bernard (1997) studied the

distribution and abundance of N. larvatus in Klias Peninsula. Such studies have provided

useful information on the behaviour and ecology, as well as on the current distribution of

the species. These are needed for managing populations of endangered species with the

main aim of preventing them or to ensure their long term survival in the wild.

3

1.2 Objectives

The present study, which was conducted in Garama, located at the Klias Peninsula in the

west coast of Sabah, is aimed at determining the current population status of

Nasalis larvatus. The specific objectives are to determine (1) the distribution of N

larvatus in Garama, Klias Peninsula; (2) the relative abundance of N larvatus in Garama,

Klias Peninsula; (3) the threats faced by N larvatus in Garama, Klias Peninsula.

CHAPTER 2

LITERATURE REVIEW

2.1 Systematic Classification of Nasalis larvatus

The Order Primates are characterized by the adaptations for increased agility in arboreal

habitats, omnivorous diets, unspecialized teeth, grasping digits, freely movable limbs,

nails on digits, reduced nasal cavity, enlarged eyes and cerebral hemispheres (Miller &

Hadey, 2002). There are three super families in this order; (1) Ceboidea or 'New World

Monkeys', (2) Cercopithecoidea or ' Old World Monkeys' and (3) Hominoidea (apes and

humans) (Strier, 2003). Cercopithecidae is divided into two subfamilies; Cercopithecinae,

which is omnivorous, and Colobinae, which is herbivorous (Cowlishaw & Dunbar, 2000).

Nasalis larvatus is a colobine monkey (Bennett & Gombek, 1993). The colobines are

unique among the primates in possessing a specialized sacculated stomach, which is

divided into pouch like sections where leaves and in some cases, highly toxic seeds, can

be digested by bacteria living in the gut (Strier, 2003).

Within the colobines, N larvatus belong to the ' odd-nosed' group of monkeys,

whose members are limited to China, Indochina and South-east Asia (Davies & Oates,

5

1994). This is a loose association of species (Bennett, 1986). Nasalis larvatus does not

have close relatives. This monkey is considered to be the only species in the genus

Nasalis. The most closely related species to N larvatus is the Simakobu Monkey (Simias

con color) of the Mentawai Islands, which a few authors classify as Nasalis concolor.

Initially, two subspecies of proboscis monkey were described, Nasalis larvatus larvatus

and Nl. orientalis. However, these are no longer considered valid and all proboscis

monkeys are now thought to belong to a single subspecies (Bennett, 1986).

In Sabah, N larvatus is known by several names, including rasong, bengkatan

and monyet Belanda (or 'Dutchman' monkey) (Payne, 1982). Their enormous, bloated

stomachs and huge pendulous nose have given rise to the name 'Dutchman monkeys' as

the animals somehow reminded people in Borneo of Europeans (Bennett & Gombek,

1993).

2.2 Morphological Features

Nasalis larvatus has a high degree of sexual dimorphism (Bennett, 1986), where males

and females can be distinguished morphologically, particularly in body size (Richard,

1985). Nasalis larvatus are large monkeys. Adult males are known to reach up to 20 kg in

weight and females about half this weight (Rod & Preston, 1999). Adult N larvatus

males can grow a body length of 75 cm, which is measured from top of the head to the

base of the tail and a tail length of 67 cm. The body and tail length of the adult females of

this species is 62 cm and 57 cm respectively (Hofer, 1994). Adult males have an enlarged

6

pendulous nose, which is its most distinct feature, whereas the females have short and

stubby noses (Bennett & Gombek, 1993). Adult males have darker cap over the top of

their heads, yellow collars and thick brown mane of fur. Females are mainly reddish

brown with flesh coloured faces. The rump patch and tail of male N larvatus are pure

white, whereas in females, these are either off-white or grey (Bennett & Gombek, 1993).

Both sexes have partially webbed hind feet which are thought to aid in swimming and

walking on mangrove mud (Bennett, 1986). Nasalis larvatus are known to swim in rivers

within mangrove forests near coastal areas (Bennett & Gombek, 1993).

New-born N larvatus are covered with sparse, blackish fur with stubby upturned

noses (Bennett & Gombek, 1993). The face is dark blue (Bennett, 1986). The fur turns

brown quickly and roughly the same colour of an adult's when the monkey is four months

old.

2.3 Distribution and Habitat

Nasalis larvatus is endemic to the island of Borneo (Payne et. aI., 1985). This species is

found in the four regions of Borneo, i.e., Kalimantan (Indonesia), Sabah and Sarawak

(Malaysia) and Brunei (Figure 2.1). In Kalimantan, N larvatus is found to occur at the

downstream parts of essentially all major rivers and severa] upstream areas (Meijaard &

Nijman, 2000). Nasalis larvatus are widely distributed along the western and far north­

eastern parts of Sarawak though their distribution is patchy (Bennett, 1986). In Brunei,

this monkey occurs along the Brunei Bay and the mangrove areas of Pulau Berambang

Banjermasin Central Kalimantan - -- .-

100 a 100 200 Kilometers

Legend

e Recent Records of Proboscis Monkeys

WZJ Protected Areas in Borneo

7

East Kalimantan

Figure 2.1 Recent records of N. larvatus in Borneo (Adapted from Meijaard and Nijman, 2000) .

8

(Yeager, 1995). In Sabah, major populations of this monkey are found on the east coast

particularly around the Dewhurst Bay area and along some parts of the Kinabatangan,

Segama and Sugut rivers (Bernard, 1997). In the west coast of Sabah, a small and patchily

distributed population is found in the Klias Peninsula (Bernard, 1997). Populations have

also been recorded at Sungai Rampayan within the Tempasuk plain in Kota Belud

(Bennett, 1986). Berhala and Sebatik Islands are the only two islands known to support

populations of N larvatus (payne et. aI., 1985).

Based on many observations, breeding populations of N larvatus are mainly

located in coastal forests, including riverine, peat swamp and fresh water swamp forests

(Meijaard & Nijman, 2000). These habitats have different zones with different types of

vegetation that occur patchily depending on distance from the coast or centre of the peat

swamp (Bennett, 1986). These monkeys are found in most of these forest zones, though it

is uncommon to find them in mixed nipah mangroves. This is attributed to the scarcity of

edible plant parts for these monkeys as compared to riverine and mangrove forests

(Bernard, 1997). Populations are occasionally found much further inland but always next

to major rivers such as the Segama and the Kinabatangan in eastern part of Sabah and at

Barito in Kalimantan (Bennett & Gombek, 1993). Solitary males have been recorded in

other forest types many kilometers away from any mangrove or large river. For example,

nomadic animals were seen briefly passing through the dipterocarp forests in the interior

of Sarawak (Bennett, 1986).

9

2.4 Social Organization

The basic social unit of N larvatus is a harem. This comprises an adult male, several

females and their offspring. The average size of a harem is nine animals (Rajanathan &

Bennett, 1990). Different harems frequently come together, particularly to roost on trees

next to rivers in the evening (Bennett & Sebastian, 1988). More than two groups

frequently sleep near to each other (Yeager, 1991). Groups of N .larvatus also meet

frequently during the day (Bennett, 1986). Juvenile males leave their natal group at a

young age to join loosely-organized and unstable all-males groups (Rajanathan &

Bennett, 1990). This all-male group also consists of one or two large males with several

small ones (Boonratana, 2002). Individuals within the same group are loosely bonded and

exchanges of members between groups can occur, particularly adult females (Rajanathan

& Bennett, 1990). Apart from harem and all-male groups, N larvatus is known to form a

third group referred to as non-breeding groups, which is dominated by males with at least

one female member (Boonratana, 2002).

2.5 Daily Activity Patterns

Nasalis larvatus have a peculiar habit of sleeping in trees adjacent to rivers every single

night (Bennett & Gombek, 1993). In the early mornings, animals usually go into the

forest away from the river in search of food. These monkeys do not often travel more than

600 m from the river because they often return to the river edges every evening. The

10

general home range size of N larvatus is a strip of 600 m forest along both sides of the

river (Bennett & Gombek, 1993).

2.6 Feeding Ecology

Feeding usually occurs at heights ranging from 1 m above ground to the crowns of mid

and upper canopy tree (Salter et. al., 1985). Nasalis larvatus are highly selective feeders

(Bennett, 1986). Unripe fruits, seeds and young leaves are usually the main food items

eaten (Yeager & Kirkpatrick, 1998). Fruits eaten are generally not sweet and succulent

but dry and bitter-tasting (Bennett & Sebastian, 1988). Nasalis larvatus do not feed on

ripe fruits because being colobine, they have specialized multi-chambered stomach and

large intake of simple sugars may cause hyperacidity of fore stomach fluid which is lethal

to the monkey (Bernard, 1997). In addition, some plants contain chemicals which can kill

the bacteria in their stomachs (Bennett & Gombek, 1993). Tree families whose seeds are

favoured by N larvatus are Leguminosae and Myristicaceae (Bennett & Sebastian, 1988).

Dipterocarpaceae, Rhizophoraceae and Sapotaceae are the best represented families of

plant species eaten by these monkeys (Salter et. al., 1985). Nasalis larvatus has the ability

to switch dietary strategies during times of low food abundance, where they start using

resources which may be poorer in nutrient quality but widely available like mature leaves

(Yeager, 1989).

11

2.7 Conservation Status

Nasalis larvatus is considered 'vulnerable' according to the mCN threat criteria

(Meijaard & Nijman, 2000) and is listed on Appendix 1 of both the Convention on

International Trade in Endangered Species (CITES) and US Endangered Species List

(Marsh & Mittermeier, 1996). Therefore, it is illegal to move this animal between

countries for commercial purposes and import permits are only given for scientific or

conservation reasons (Bennett & Gombek, 1993). Nasalis larvatus is also rated as a

'highly threatened' species in Sabah, according to the priority ratings of surveys for

specific primate populations in Asia (Eudey, 1987). In Sabah, this species is listed under

Schedule 1 Part 1 of the Wildlife Conservation Enactment 1997, which makes this

monkey fully protected.

In Kalimantan, N. larvatus population is estimated to be more than 250,000

animals, with less than 5000 animals inside protected reserves (Meijaard & Nijman,

2000). There are around 16 conservation areas in Kalimantan, where seven areas are

partially included in the protected area network system. In four of these areas,

conservation measures seem to be completely inadequate for the long-term protection of

the N. larvatus populations. The areas are Pulau Kaget, Tanjung Puting National Park,

Kutai National Park and Kendawangan Nature Reserve where these monkeys are facing

threats like insufficient food resources, habitat loss due to illegal logging, gold mining

and forest fires (Meijaard & Nijman, 2000).

12

In Sarawak, these monkeys are protected in the Samunsam Wildlife Sanctuary,

Maludan River, Bako National Park, Sarawak Mangrove Forest Reserve, Semantan

mangroves, Rajang Delta and Limbang-Lawas mangroves (Salter et. at., 1985). About

10% of the total population size of this species is found in officially gazette protected

area. Among the major threats faced by these monkeys are illegal logging and hunting

(Bennett, 1986).

In Brunei, N larva/us is protected in the mangrove areas of Pulau Berambang and

the whole ofPulau Siarau along the Brunei Bay (Bennett, 1986). The Wildlife Protection

Enactment passed in 1978, listed N larvatus as one of the 34 protected species that

cannot be hunted or exported. Brunei has a high level of wildlife protection because the

export of wildlife is never important in Brunei, guns have been prohibited since 1962 and

timber extraction is only allowed in areas allocated by the government (Mittermeier,

1996). Unfortunately, hunting and logging in Sarawak is causing the populations along

the Brunei Bay to decline when these monkeys cross into Sarawak (Bennett, 1986).

In Sabah, major populations of this monkey are found on the east coast

particularly around the Dewhurst Bay area and along the some parts of the Kinabatangan,

Segama and Sugut rivers (Bernard, 1997). In the west coast of Sabah, a small population

of Nasalis larvatus is found in the Klias Peninsula and at Sungai Rampayan within the

Tempasuk plain (Bennett, 1986, Bernard, 1997). A preliminary estimate of the population

of N larvatus in Sabah showed that at least 2000 animals occurred throughout the state

(payne, 1982). Logging of the mangroves for woodchips was widespread that the

43

REFERENCES

Bennett, E.L., 1986. Proboscis Monkeys in Sarawak: Their Ecology, Status, Conservation

and Management. World Wildlife Fund Malaysia, Kuala Lumpur.

Bennett, E.L. and Sebastian, A.c., 1988. Social organization and ecology of Proboscis

Monkeys (Nasalis larvatus) in mixed coastal forest in Sarawak. International

Journal of Primatology 9,233-255.

Bennett, E.L. and Gombek, F., 1993. Proboscis Monkeys of Borneo. Natural History

Publications (Borneo) Sdn. Bhd., Kota Kinabalu.

Bernard, H, 1997. Some aspects of behaviour and feeding ecology of the Proboscis

Monkey, Nasalis larvatus, based on the brief study in the Klias Peninsula, Sabah.

Borneo Science 3, 65-84.

Bernard, H., 1997. A study on the distribution and abundance of Proboscis Monkey

(Nasalis larvatus) in the Klias Peninsula. The Journal of Wildlife Management

and Research Sabah 1, 1-12.

Boonratana, R , 2002. Social organization of proboscis monkeys (Nasalis larvatus) in the

Lower Kinabatangan, Sabah, Malaysia. Malayan Nature Journal 56, 57-75.

Cowlishaw, G. and Dunbar, R, 2000. Primate Conservation Biology. The University of

Chicago Press, United States of America.

Davies, AG. and Oates, J.F., 1994. Colobine Monkeys: Their Ecology, Behaviour and

Evolution. Cambridge University Press, Great Britain.

44

Budey A.A., 1987. Action Plan/or Asian Primate Conservation: 1987-91. University of

California, Riverside.

Galdikas, B.M.F., 1982. The Orang Utan: Its Biology and Conservation. Kluwer

Academic Publishers, Netherlands.

Hofer, H., 1994. Insight Guides: Southeast Wildlifo Asia. APA Publications Ltd,

Singapore.

Goossens, B., SetcheIl, J.M., Datu Md. Abbam Abulani, Mohd. Fairus Jalil, Suzita

Sheena James, Sailun Hj. Aris, Maklarin Hj. Lakim, Agung Daudi Seventri, Selly

Sitha Sariningsih and Ancrenaz, M., 2003. A boat survey of primates in the Lower

Kinabatangan Wildlife Sanctuary. Lower Kinabatangan Scientific Expedition

2002. University Malaysia Sabah, Malaysia.

Marsh, C.W. and Mittermeier, RA., 1987. Primate Conservation in the Tropical Rain

Forest. Alan R Liss, Inc., New York.

Meijaard, M. and Nijman, v., 2000. Distribution and conservation of the Proboscis

Monkey (Nasalis larvatus) in Kalimantan, Indonesia Biological Conservation 92,

15-24.

Miller, S.A. and Harley, J.P., 2002. Zoology 5th Edition. The Mc Graw Hill Companies,

Inc, New York.

Mittermeier, R.A., 1996. Brunei protects its wildlife. Oryx 16, 67-70.

Mittermeier, RA. and Konstant, W.R, 1996. Primate conservation: A retrospective and a

look into the 21 st century. Primate Conservation 17, 7-17.

45

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