Final Report_Le Thi Dien

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Conservation of the Red-Shanked Douc Langur

(Pygathrix nemaeus nemaeus) in Bach Ma National Park,

Vietnam

Final Report

Prepared for

Peoples Trust for Endangered Species (PTES)

By Le Thi Dien

April, 2009


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Executive Summary:

The red-shanked douc langur (Pygathrix nemaeus nemaeus), is an endangered

monkey distributing in Vietnam, Lao, and Cambodia. Through this study, we

reported the total number of animals observed during the study is 22 animals

(estimate 26 animals). The survey area is 130 km2. Therefore, current population

density estimated was 0.17 individuals per km2. P. nemaeuswere mainly found at

elevation between 500 and 1.300m above sea level in Bach Ma National Park.

Groups of P. nemaues often distribute in restoration forest habitat or tropical

broadleaf evergreen rain forest habitat. A total of 41 belonging to 25 families were

observed eaten by P. nemaeus at Bach Ma National Park. One of the most

important finding is we add fifteen new tree species used by P. nemaeus to the

existing food list. P. nemaeus were observed feeding on variety of food items

including leaves, buds, flower buds, flowers, fruits, and bamboo shoots. We also

recognised that three main threats to P. nemaeuswere identified during the study,

including hunting, habitat destruction and tourism. Two senior students were

instructed to do research and three training courses were be organized to improve

conservation awareness of the BNP staffs, students of Hue University of Agriculture and

Forestry, and local people in endangered primate species survey and monitoring.

INTRODUCTION

The colobine monkeys of the genus Pygathrixare native to Indochina. Until only ten years

ago, just two distinct taxa were recognized: the red-shanked douc, Pygathrix nemaeus,

named by Linnaeus in 1771, in the northern part of Central Vietnam and Central Laos;

and the black-shanked douc, P. nigripes, from South Vietnam and east Cambodia,

described exactly a century later by Milne-Edwards. In Vietnam the douc langur is found

from Tay Ninh province to Nghe An province (Pham, 1993). Red-shanked douc langurs(Pygathrix nemaeus nemaeus) are found in Bach Ma National Park, and black-shanked

douc langurs (Pygathrix nemaeus nigripes) are found in Nam Cat Tien National Park in

Vietnam (Eames and Robson, 1993). Both the red and black-shanked douc langurs are

found in Kong Cha Rang, Kon Khi Kinh, and Mom Ray Nature Reserves (Lippold, 1995)1.

1 http://www.theprimata.com/pygathrix_nemaeus.html


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The beautiful red-shanked douc langur is only found in north and central Vietnam and

Laos. Its habitat is in the lowland to montane primary and secondary rainforest where it

lives in the mid to upper levels of the canopy2. They live in moist tropical rain forest but

have also adapted to dry (monsoon) forest (Camille Dorian, 2002).

The red-shanked douc langur has been listed as EN A1cd (IUCN Red List ver 2.3 (1994)),

Appendix I (CITES), Endangered (Red Book on Fauna of Vietnam, 2004), and category IB

(Decree 32/2006/ND-CP of Vietnam). However, their population sizes in the wild appear

to decline because of several conservation problems. Firstly, habitat loss and forest

fragmentation is one of the most important factors threatening this species. The loss of

natural forest by war, logging and the replacement of secondary natural forests by

commercial plantation forests in the area has reduced the quality and quantity of natural

habitat drastically. Secondly, it is currently known as one of the most popular primates inthe food and pet trade. They are considered a delicacy all over Southeast Asia. In

addition, it is also in danger of becoming medicinal products because some traditional

oriental medicines use douc langur body parts (Camille Dorian, 2002). Under pressure

from hunting and habitat loss, the number of this species is dwindling fast. Lastly, limiting

on skills of species monitoring and conserving of conservationists due to lacking the

specific information of species as well as non-participating of local communities on wildlife

conservation is another cause of the decline of this species in nature. Without immediate

and decisive conservation action, these species are likely to become extinct very soon 3.

There have been conservationists doing researches into distribution, population size and

diet of the species. Pham Nhat (1993) investigated into 49 floras of 22 fammilies used as

food by P.nemaeus. Some authors have identified the occurrence of the species in Bach

Ma Natonal Park such as Eames & Robson, 1993; Lippold, 1995; Matsumarra, 1997;

Huynh Van Keo and Van Ngoc Thinh, 1998. However, due to the high hunting pressure in

Bach Ma National Park, douc langur populations have considerably reduced (Vu Ngoc

Thanh, pers. comm.).

Therefore, data on biology, ecology, distribution, population abundance, and threats of thespecies is vital for long-term conservation and management recommendations. Training

courses and participating on project activities will provide local people, conservationists,

2 http://www.blueplanetbiomes.org/redshanked_douc_langur.htm

3 WWF


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young researchers, students, and others with the necessary skills for conserving this

species.

AIMS OF PROJECT

The overall aim of our project is to obtain information useful for the better monitoring and

conservation of the Red-Shanked Douc Langur (Pygathrix nemaeus nemaeus) in

particular and primate species in general in the central region of Vietnam. Hiring local

people and Bach Ma National Park staffs as field assistants within this project and training

courses will allow for the capacity development and conservation awareness of

stakeholder members.

Through the study, we intend:

(1) To identify the distribution and abundance of P. nemaeus;

(2) To study the ecology and behavior of P. nemaeus;

(3) To assess current and potential threats to P. nemaeus and its natural habitats and

propose possible solutions to the species conservation;

(4) To promote conservation awareness through employment and capacity development

of Bach Ma National Park staffs, students of Hue University of Agriculture and Forestry,

and local people in endangered primate species survey and monitoring;

(5) To make appropriate conservation and management recommendations for the species

and its habitats.

METHODS

1. Research site

Bach Ma National Park is located in the Central Truong Son, is a strip of forest connecting

the border between Lao and Vietnam with the East Sea. This National Park with high

biodiversity is the habitat of many rare plants and animals. Among those is P. nemaues.According to rangers experience, We have determined distribution sites of P.nemaeus in

sub-areas 207, 209, 210, 211, 214, 227, 229, 230, 231, 375, 384, 385, and 386 of the

National Park, the total scale of these areas is estimated to be 130km2. Thus, the

research areas are determined in the scale of 130km2 in these sub-areas.


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Study site was selected based on local informants and previous reports. Five transects

were established within the langurs known habitats:

(i) Transect 1: Bach Ma summit - Coldebay: two expeditions;

(ii) Transect 2: Km 14 Bach Ma - Tri Sao waterfall: one expedition;

(iii) Transect 3: Km 14 Bach Ma - Truoi lake: one expedition;

(iv) Transect 4: Bach Ma summit - Lien Chi slope: one expedition.

2. Research Time

The study was carried out from November, 2008 to May, 2009 in Bach Ma National Park.

In the first month we interwiewed rangers of Bach Ma National Park to collect data of the

times they encountered P.nemaues, the plants used as food by P. nemauesand threats

to the species, and identified line-transects.

In the rest months, we implemented field investigations in line-transects to collect data of

distribution, population size, food plants of the species and threats to it. Each expedition

was investigated in one day per month. The total number of days spent on field

investigation is 30.

3. Methodology

3.1. Interview

We carried out interviews with villagers, hunters, and experienced staffs of Bach Ma

National Park to determine the most likely places for encountering the species. These

interviews also provided information on the current and past distribution and population

size of the species, the list of food eaten by this species, as well as the threats to this

species in the study area.


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Figure 01. The Map of observed transects

3.2. Forest survey

(+) Investigation into the species distribution status and population size

Investigation in each line-transect was carried out to observe the occurrence of P.

nemaeus. The time for observation was from 6: am to 6: pm. In addition, all signs such as

tracks, faeces, feeding signs, vocalizations, etc. was noticed to determine distribution of

this species.

(+) Food

All samples of food plants and potential food were collected from areas known to be in the

range of the monkeys.Representative samples of food eatenwere selected from trees in

which monkeys would be observed feeding. Additional samples were chosen from trees

judged to be common in the habitat.


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(+) Threats

Threats to the species are identified through interviewing rangers, field observation, and

the levels of threats are arranged according to the criteria: (+) range of impacts (total

impacts in the park or partly impact), (+) intensity of impacts (strongly impact or slightlyimpact).

Surveying in the field

3.3. Training and workshop:

- Three field training courses will be organized to improve conservation awareness of the

BNP staffs, students of Hue University of Agriculture and Forestry, and local people in

endangered primate species survey and monitoring.

- A workshop among the related stakeholders (Conservationists of Bach Ma National

Park, local authorities, local people, research team members, staffs of the Green Corridor

Project, Staffs of NGOs related to conservation in Thua Thien Hue Province, students of

Hue University of Agriculture and Forestry) by the end of the project will be organized to

present the research findings; have discussions; receive comments from participants to

finalize the research report; and create a network for research and primate conservation

among stakeholders.

RESULTS

1. Population status

Three groups and one solitary juvenile female of P. nemaeus were recorded based on

direct observations and informants during the study. The number of animals and age/sex

composition of 3 groups observed are presented in table 01.


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The highest count for a single group was 10 animals (estimated 12 animals) and the

lowest count for a single group was 5 animals (estimated 7 animals). Average group size

is 7 animals. The estimates were based on evidences such as branch movements and

vocalizations. Juveniles were seen in all three groups. An Infant clinging an adult female

was observed in group 3 in July 2008. The infants/adults ratio is 1: 2.75. It was difficult to

identify sexes of adults in the field since the groups observed traveled fast and

observations were made at distance. Further, animals appeared to be wary of observers

and they often fled away when detected observers.

Table 01. Population sizes ofRed-shanked douc langur in BMNP

No. Count EstimateAdult

Male

Adult

femaleJuveniles Infants

Solitary 1 1 1 (female)

Group 1 5 7 ? ? 2

Group 2 6 6 ?2 ?2 2

Group 3 10 12 ? ? 2 1

TOTAL 22 26 7 1

The solitary juvenile was rescued and released to the forest by forest rangers in July,

2007 when it was confined in a cage. Local people said that they had caught this Langur

in April, 2006. Meanwhile, the Langur was about 4-5 months old, it was in burned status

because it had been carried by his mother to near the field which was being burned for

afforestation. At the time being rescued, this Langur was about 20 months old and in good

health condition. When it is released, at first it only fed around the burnt-over land. Later, it

moved gradually to the top, it is currently seen at an altitude of 600-700m. Although living

close to the group of 5-7 langurs (2 km far from this group), the animal appeared not to

integrate with neighboring groups since she always traveled, fed and rested alone and

kept distance with neighboring groups.

The total number of animals observed during the study is 22 animals (estimate 26

animals). The survey area is 130 km2. Therefore, current population density estimated

was 0.17 individuals per km2.


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2. Distribution

The locations and elevations of 3 groups and a solitary female juvenile of Pygathrix

nemaeusare shown in table 2.1. P. nemaeuswere mainly found at elevation between 500

and 1.300m above sea level in Bach Ma National Park. According to local reports,Pygathryx nemaeus were often seen in CHO DEN (Prashorea stellata) forest and

surrouding areas. These groups sometimes shift from Truoi Pond to Morin for feeding.

Table 02. Distribution of 3 groups and a solitary juvenile female of

P. nemaeusat BMNP

No. Elevation (m) Locations Habitats

Solitary 18-678 N:16017,185

E:107010,126

N: 16013,125

E:107096,337

Burnt-over land, tropical

broadleaf evergreen rain forest

(poor forests)

Group 1 491-953 N:16016,231

E:107013,577

to N: 16012,156

E:107092,720

Tropical broadleaf evergreen

rain forest (secondary forest

after logging-young forests) and

sub-tropical broadleaf evergreen

rain forest (rich forests)

Group 3 1,375 N:16011,763

E:107051,755

Sub-tropical broadleaf evergreen

rain forest (poor and rich forests)

Group 4 1,150-1,336 From N: 16011,833

E:107050,729

to N: 160

11,856

E:107050,739

Sub-tropical broadleaf evergreen

rain forest (medium and rich

forests)

The distribution of the P. nemaeusare shown by Figure 02.

In Bach Ma National park, groups of P. nemaues often distribute in restoration forest

habitat or tropical broadleaf evergreen rain forest habitat. However, the species has a


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wide range for feeding, from field habitat in the Park foot (in altitude of 18m) to sub-

tropical broadleaf evergreen rain forest (in altitude over 900m).

The Investigation and interviews show that the P. nemaues lives and feeds on many

different types of forests. However, it only occasionally feeds on poor forest habitat withforest structure is broken down completely, the cover is


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3. Organization and Behaviour of the P. nemaeusin research sites

3.1. Social system

The social system of P. nemaeusvaries between a unimale and a multimale-multifemale

system. The social system of the P. nemaeus depends on the roles played by each

individual in the group. In each group, there will be one adult male P. nemaeusby whom

the power of the group is held and most of the important activities of the group are

organized. In addition, male and female individuals of this species are also found living

alone in forests. A ratio of one male and one female is often found in each group of the P.

nemaeus. Females have a higher tendency to groom males in multimale groups than in

unimale groups.

In research sites, most of the time P. nemaeusis found living in groups with an adult male

P. nemaeus leading. When discovering strange sounds, they often inform others of

dangers by growling. Then, they begin their movements through the forest canopy to other

areas in the forests while carefully turning back to observe and growling. In each group,

mature individuals often get food for others, especially for younger individuals in the

group. Infants are often carried ventrally when they are foraging for food or making their

movement through forest canopy. Basing on the times of their occurrences that were

observed, this species can be said to live and move among branches of trees usually.

Sometimes, they also feed on the ground.

Thus, the social organization system of the P. nemaeushas common features with those

of other kinds of Primate living in groups on trees.

3.2. Behaviour

The P. nemaeus is one of the species of langurs lives on trees and carries out their

activities at day-time. They live in the mid to upper levels of the canopy.

* Daily activities:

Daily activities of this species consist of playing, climbing, jumping up

and down in one place, stooping, hanging, and swinging from

overhead supports. Contact between individuals during play consists

of touching, pulling, mouthing, wrestling, and chasing. in social play,

immature group members tend to play more than adults. The most

popular times for play are just after eating time and before resting at night.


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Figure 03. Percentage of time for daily activities of the P. nemaeus

Thus, most of the time in a day is used for feeding and resting. Resting time takes the

highest percentage with 13 hours and 55% of a day time. Feeding time is about 8.5 hours,

take 35% of a day time, and 2.5 hours left is play time, take 10% of a day time.

* Parental care and protection:

Movement of the group is led by the adult males with females and infants in the center

and juvenile males bringing up the rear (Lippold, 1998). Infants are often carried ventrally

by their mothers or adult members when the group is moving or feeding. Sometimes,

group members break off part of a branch with leaves and give it to another group

member (Kavanagh,1978).

* Hiding behaviour:

When hearing strange sounds, they often hide themselves behind canopies and huge

branches, adult or mature individuals growl to inform others of dangers and move to

another place (according to people who have encoutered the P. nemaeus in Bach MA

national Park).

4. Diet

4.1. Food composition

A total of 41 belonging to 25 families were observed eaten by P. nemaeusat Bach Ma

National Park (Table 04; figure 04). Euphorbiaceae, Moraceae, and Poaceae families

have largest number of tree species used by P. nemaeus(4 species). This was followed

55%10%

35%

n

Chi

Ngh


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by Sapindaceae (3 species). Anacardiaceae, Clusiaceae, Dilleniaceae, Fagaceae, and

Meliaceae families contributed two species to the food list. The rest was eaten only one

species by P. nemaeus.

Table 04. List of food plant and plant part eaten by P. nemaeusat BMNPTT Latin name Family Part eaten

1 Saurauia tristyla Actinidiaceae Leaves, fruits

2 Allospondias lakonensis Anacardiaceae Leaves, fruits

3 Dracontomelum duperreanum Anacardiaceae Leaves, fruits

4 Schefflera octophylla Araliaceae Leaves

5 Canarium album Burseraceae Leaves, fruits

6 Peltophorum tonkinense Caesalpiniaceae Fruits, flowers

7 Garcilinia mangostana Clusiaceae Leaves

8 Garcilinia oblongfolia Clusiaceae Leaves, buds

9 Ipomoea batatas Convolvulaceae Leaves

10 Trichosanthes kirilowii Cucurbitaceae Leaves, buds, fruits

11 Dillenia heterocephala Dilleniaceae Fruits

12 Dillenia indica Dilleniaceae Leaves, fruits

13 Prashorea stellata Dipterocapaceae Leaves, buds

14 Baccaurea ramiflora Euphorbiaceae Leaves, fruits

15 Bischofia javanica Euphorbiaceae Leaves, fruits

16 Endospermum chinense Euphorbiaceae Fruits

17 Macaranga denticulata Euphorbiaceae Leaves

18 Castanea mollisima Fagaceae Fruits

19 Castanop sisbosii Fagaceae Fruits

20 Gnetum montarum Gnetaceae Fruits

21 Engelhardtia spicata Juglandaceae Leaves

22 Aglaia korthalsii Meliaceae Leaves

23 Chisocheton paniculatus Meliaeae Leaves, fruits

24 Adenanthera microperma Mimosaceae Leaves, flowers

25 Artocarpus rigidus Moraceae Leaves, buds, fruits

26 Ficus glomerata Moraceae Leaves, fruits

27 Ficus hispida Moraceae Fruits, buds

28 Ficus vasculosa Moraceae Leaves, fruits


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TT Latin name Family Part eaten

29 Musa cocinea Musaceae Leaves, fruits

30 Eugenia brachiata Myrtaceae Fruits

31 Averrhoa carambola Oxalidaceae Fruits, Flowers

32 Bambusa spinosa Poaceae Bamboo shoot

33 Dendrocalmus pattelaris Poaceae Bamboo shoot

34 Neohouzean dullosa Poaceae Bamboo shoot

35 Thysanoloena maxima Poaceae Flower buds

36 Euphoria longana Sapindaceae Fruits

37 Mischocarpus sundaicus Sapindaceae Leaves

38 Nephelium chryseum Sapindaceae Fruits

39 Madhuca pasquieri Sapotaceae Fruits40 Scaphium macropodum Sterculiaceae Leaves

41 Grewia paniculata Tiliaceae Fruits

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Euphorbiaceae

Moraceae

Poaceae

Sapindaceae

Anacardiaceae

Clusiaceae

Dilleniaceae

Fagaceae

Meliaceae

Actinidiaceae

Araliaceae

Burseraceae

Caesalpiniaceae

Convolvulaceae

Cucurbitaceae

Dipterocapaceae

Gnetaceae

Juglandaceae

Mimosaceae

Musaceae

Myrtaceae

Oxalidaceae

Sapotaceae

Sterculiaceae

Tiliaceae

Familyname

Species numbers

Figure 04. Tree families eaten by P. nemaeusin Bach Ma National Park


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4.2. Food items

P. nemaeus were observed feeding on variety of food items including leaves, buds,

flower buds, flowers, fruits, and bamboo shoots (Table 04). The proportion of tree species

used by P. nemaecus according to food items is shown in figure 05. Fruiting treesappeared to be preferred food trees of the langurs, contributing the largest proportion to

the total food list (26 species, 63.41%). This was followed by trees producing leaves (24

species, 58.54%); buds (5 species, 12.20%). Trees producing flowers and bamboo shoots

were made up an equal proportion of food trees in the food list (3 species, 7.32%). Only

one tree species producing flower buds used by the langurs (2.44%).

0

4

8

12

16

20

24

28

32

Items

Species eaten

Series1 24 5 1 3 26 3

Leaves Buds Flower buds Flowers FruitsBamboo

shoots

Figure 05. Percent of tree species eaten by P. nemaeus

according to plant parts


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Faeces, feeding signs of P. nemaeusin research sites

4. Some charecteristics of forests where the P. nemaeusdistributes:

At each site where Red-shanked douc langur distributes, we made investigation in 2

sample plots with the same forest status, each sample plot covers an area of 1,000m2, the

total area investigated is 0.8ha. In each sample plot, trees with diameter 6cm were

measured and counted. The results are indicated in the table below:

Table 05. Charecteristic of forest status where Red-shanked douc langur distributes

Forest status Sample plotN/a sample

plot (tree)N/ha(tree) D1.3 (cm) Hvn (m)

1 27 270 15.77 18.70

2 28 280 15.00 17.75IIIA1

TB 27.5 275 15.39 18.23

3 20 200 17.77 19.65

4 32 320 18.58 19.75IIIA2

TB 26 260 18.18 19.70

5 30 300 21.19 20.60

6 28 280 20.75 20.15IIIA3

TB 29 290 20.97 20.38

7 34 340 31.79 22.13

8 32 320 32.00 24.10IIIB

TB 33 330 31.90 23.12


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Percentage of plant species in divisions is indicated clearer in figure 06:

12%10%

76%

2%

Thng t (Lycopodiophyta)

Dng X(Polypodiophyta)

Thng (Pinophyta)

Ngc lan (Magnoliophyta)

Figure 06: percentage of plant divisions

It can be realized that plant species composition in areas where the P. nemaeus

distributes mainly belongs to Ngoc lan division (39 species, 76% of the total species of

divisions). Magnoliophyta takes the highest percentage in number of familia and species

in these areas since this is a division with huge range of favorite trees used for food by the

P. nemaeus.

6. Threats

Three main threats to P. nemaeus were identified during the study. They are hunting,

habitat destruction and tourism.

Hunting:

Traps are considered the most currently serious threat to the primates and other wildlife in

the areas surveyed. A variety of traps were widely seen during the surveys, especially in

CHO DEN (Prashorea stellata) forests. The most common traps used by local people are

string traps that are able to capture birds, small and large mammals, especially primate

species. Guns and hunting dogs did not be seen during the surveys.

Habitat destruction:

- Non-Timber Forest Products collection (NTFPs): Local people living in buffer zone often

go to the forests to collect NTFPs such as woodfire, (Livistona bracteata) for roof,

weaving, or sale, Rattan (Calamus spp.) for household use, making handcraft items, or


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sale, Wild broom (Thysanoloena maxima) forhousehold use and sale . These activities

directly affect P. nemaeus behavior. For example, the langurs often seen feeding on

flower buds of Thysanoloena maxima, but this species was widely exploited by local

people for household use and sale.

- Illegal logging: In general, illegal logging has been successfully controlled by forest

rangers and is not considered as a major threat to the langurs in the areas surveyed.

However, there are still some local people living in buffer zone are seen exploiting a

certain kind of tree species for selling such as Hopea siamensis, Prashorea stellata,

Afzelia xylocarpa during non-crop season. This may partly influence on the langurs

habitat integrity.

Tourism:

Tourist activities have recently been paid attention and developed in Bach Ma National

Park. Infrustructures such as roads, hotels, guest houses are often contructed within the

langurs known habitats. These activities may influence on normal behavior of populations

of P. nemaecussuch as noises from tourists. However, based on recent observations, the

langurs appeared to be familiar with the presence of tourists and the noises. For example,

the groups of P. nemaeuswere seen at close distance to the hotels and tourist roads.

DISCUSSION

1. Population status

Arcording to Nadler (2003), in the observations in areas previous to the spraying of Agent

Orange, Osgood (1932) reported groups of 30 to 50 individuals of Red-shanked douc

langur in Bach Ma National Park. In contrast, Lippold (1995b) found group-sizes of no

more than 20 at Bach Ma. One group of 3 to 4 Red-shanked douc langurs was seen by

Eames & Robson (1993) in January 1990 in secondary forest during a primate survey in

southern Vietnam. The same team observed one single male in February 1990 in primary

forest at an altitude of 700 m. Lippold (1995a) reported sightings of three groups of 5, 15

and 20 individuals in primary and secondary forest during surveys conducted in 1994 and

1995. In "Preliminaly study on ecology and behaviour of the Red shanked douc langur in

Bach Ma National Park", Huynh Van Keo and Van Ngoc Thinh (1998) reported two

sightings by park forest guards before September 1994 and in August 1996 of groups with


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about 5 and 10-15 animals. In May 1997, Matsumura discovered a group of about 5 to 7

individuals (Huynh Van Keo & Van Ngoc Thinh, 1998).

The current population is not comparable to previous reports (table 07). In comparison

with the population of the species before the war, the population of P. nemaues in BachMa National Park decreased remarkable (estimated to decline a half compared to the

report of Osgood (1932). However, in comparison with investigation of Lippold and

(1995a) and Huynh Van Keo and Van Ngoc Thinh (1998), the population of the P.

nenameusdoes not have much change along with the time. In this research, we found out

an animal which was rescued and released to the forest by rangers in 2007. Nevertheless,

if comparing in population sizes, we could recognize that from 1995 till now, the

population sizes has declined from 40 animals (1995) to 30 animals (1998) and only 26

animals now. Moreover, we also realized that in the group of 10-12 animals, there was amother Langur carried an infant. This showed that, the number of individuals decreasing is

more than that because there had been adults replaced by infants.

Table 07. Comparision of current population size of P. nemaeus

with previous reports

No Sites Population sizeNumber of

groupsobserved

References

1 Bach Ma 30-50 ? Osgood, 1932

2 Bach Ma 3-4

1

1

1

Eames & Robson, 1993

3 Bach Ma 40 3 Lippold, 1995a

4 Bach Ma 20 ? Lippold, 1995b

5 Bach Ma 5-7 1 Matsumura, 1997

6 Bach Ma 30 3 Huynh Van Keo and Van

Ngoc Thinh, 1998

7 Bach Ma 22-26 4 This study

2. Distribution


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The beautiful red-shanked douc langur is only found in north and central Vietnam and

Laos. Its habitat is in the lowland to montane primary and secondary rainforest where it

lives in the mid to upper levels of the canopy (Camille Dorian, 2002). In Vietnam the douc

langur occurs primarily below 1500 meters (Eames and Robson, 1993).

In Bach Ma National Park, P. nemaeus is often found in primary and secondary tropical

broadleaf evergreen rain forest habitats below 1.500 m above sea level. This supports

Eames and Robson (1993)s findings. A possible explanation for these similarities is that

most langurs feeding trees are widely distributed below 1.500 m above sea level. They

include Parasorea stellata, Garcilinia oblongfolia, Bischofia javanica, Endospermum

chinense, Peltophorum tonkinense, Canarium album, Nephelium chryseum, Schefflera

octophylla, Dendrocalmus patellaris, Neohouzean dullosa, Ficus hispida. Further,

populations of P. nemaeus are frequently seen in Prashorea stellata forests that havebeen reported by Huynh Van Keo and Van Ngoc Thinh (1998).

3. Diet

Table 08. Comparision of tree species and families eaten by P. nemaeusbetween

current study and previous reports

Refferences No. of family (%) No. Of species (%)

Pham (1993) 22 100 49 100

This study 25 95.45 41 65.31

The current food list recorded is less than Pham (1993)s finding in terms of number of

tree species and families eaten by P. nemaeus (table 07). The possibility for this

difference is Pham (1993) appeared to report food list for the whole Vietnam populations

of P. nemaeuswhereas this study just focuses on Bach Ma National Park site.

One of the most important finding is we add fifteen new tree species used by P. nemaeus

to the existing food list. They are Saurauia tristyla, Schefflera octophylla, Ipomoea

batatas, Trichosanthes kirilowii, Dillenia indica, Prashorea stellata, Baccaurea ramiflora,Bischofia javanica, Macaranga denticulate, Engelhardtia spicata, Aglaia korthalsii,

Artocarpus rigidus, Thysanoloena maxima, Mischocarpus sundaicus, and Scaphium

macropodum. Thysanoloena maximaappeared to be heavily exploited by the langurs in

April coincide with when this tree flowering.


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P. nemaeusin Bach Ma appeared to exploit the same food items as in other areas. They

ate leaves, buds, flowers and flower buds, fruits, young stems, and bamboo shoots

(Pham, 1993; Wisconsin, 2002). However, the proportion of food items in the diet of P.

nemaeus in Bach Ma is different from that in previous reports. Wisconsin (2002) reported

that Douc langurs diet comprises mainly leaves (82%) while populations of P. nemaeusat

Bach Ma consumed more fruits than any other types of food. The difference may be a

result of differences in methodology and study season. Long-term phenological monitoring

in the study area may be an answer for the difference.

4. Threats

Hunting and habitat destruction have been recognized as the major threats to the wild

populations of P. nemaeus(Nadler et al., 2004; Timmins and Duckworth, 1999). In Bach

Ma, although illegal logging and NTFPs collection are going on (Gilmour and Nguyen Van

San, 1999), these activities just operate at small scales and are widely controlled by

National Park staffs, indicating that habitat destruction may have little impact on the

populations of P. nemaeusat Bach Ma. Currently, traps and tourist activities are identified

as the major threat to the langurs in Bach Ma. The degree of impact of these activities on

the populations of P. nemaeushas not been assessed yet, future research should look at

how impact of tourist activities on the langurs are and what types of traps do the local

people use to capture primates as well as wildlife in general.

TRAINING AND EDUCATIONAL ACCOMPLISHMENTS

We instructed a senior student to do research with the topic "Distribution, population

status and ecology of P. nemaeus in Bach Ma national Park" and he greatly got the best

mark (10/10).

Three field training courses were be organized to improve conservation awareness of the

BNP staffs, students of Hue University of Agriculture and Forestry, and local people in

endangered primate species survey and monitoring.

Currently,we are guiding a senior student to do research on "Distribution, population

status, ecology and conservation of P. nemaeus in Bach Ma national Park" with the

research area expanded wider in comparison to previous research areas.


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Training for students in the field

Training for local people

RECOMMENDATIONS

1) Strengthening protection of the species and habitat

- Plan for tightly monitoring of the areas where the P. nemaeusdistributes, especially the

areas inside and around CHO DEN (Prashorea stellata) forest.

- Strengthen investigation, preventing local people in the buffer zone from trapping in the

forest. Penalize local people who break the law. Remove traps set in the forest.

- Monitor tightly activities of local people to exploit NTFPs; limit local people exploit NTFPs

for food in the distribution sites of the P. nemaeus.

- Manage tightly eco-tourism activities; forbid tourists make noises that impact on the

species.


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2) Doing more researches in the species

- Extend the research scale to supplement data of distribution and population sizes of the

species in different points of time in a year.

- Carry out more researches in food plants in different seasons of a year.

3) Improve communities' awareness

- Propagandize law of forest protection and wildlife protection for local people.

- Organize courses about the important role of the species as well as the need to protect

the species for local people.

ACKNOWLEDGMENT

I would like to thank to Bach Ma National Park for the support and permission. Special

thanks to forest rangers for their dedicated participation and assistance. Thanks to Hue

University of Agriculture and Forestry for giving time and supporting field equipment to

conduct this study.

We also thank to Vietnam Forestry University for sending experts to conduct this study.

Thanks to People's Trust for Endangered Species for financial support.

REFERENCES

Camille Dorian, 2002. Mokeys of Asia: The Endangered Douc Langur. Mokey Matters

Website.

Eames, J. C., and Robson, C. R., 1993. Threatened primates in southern Vietnam. Oryx

27: 146-154.

Gilmour, D. A. and Nguyen Van San, 1999. Buffer zone management in Vietnam. Hanoi:

IUCN Vietnam.

Ha Thang Long and Le Thien Duc, 2001. Primate Survey Report with special emphasis of

the Blackshanked Douc langurs (Pygathrix nigripes) in Binh Phuoc and Dak Lak

Provinces, South Vietnam. Unpublished report Frankfurt Zoological Society.

Huynh Van Keo and Van Ngoc Thinh, 1998. The Status of Douc Langur (Pygathrix

nemaeus) and some Preliminary Results of Wildlife Conservation in Bach Ma


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National Park. Proceedings Workshop on a Conservation Action Plan for the

Primates of Vietnam. Hanoi.

Huynh Van Keo and Van Ngoc Thinh, 2002. Preliminaly study on ecology and behaviour

of the Red shanked douc langur (Pygathrix nemaeus nemaeus) in Bach MaNational Park and suggestions for possible ways of protection. Bach Ma National

Park and Nagao Natural Environment Foundation.

Lippold, L. K., 1995. Distribution and conservation of the Douc Langur (Pygathrix

nemaeus) in Vietnam. In: Xia Wuping and Zhang Yongsu (eds.) Primate

Research and Conservation. China Forestry, Beijing.

Lippold, L. K., and Vu Ngoc Thanh. 1995. Douc langur variety in the central highlands of

Vietnam. Asian Primates 5(1-2): 6-8.

Mittermeier, R.A. & D.L. Cheney. 1987. Conservation of primates and their habitats,

pages 477-490 in B.B. Smuts, D.L. Cheney, R.M. Seyfarth, R.W. Wrangham, &

T.T. Struhsaker (eds). Primate Societies, University of Chicago Press, Chicago.

Pham, N. 1993. First results on the diet of the red-shanked douc langur, Pygathrix

nemaeus. Australian Primatology. Vol. 8, 5-6.

Tilo Nadler, Frank Momberg, Nguyen Xuan Dang, Nicolas Lormee, 2003. Vietnam

Primate conservation status review 2002 - Part 2: Leaf Monkeys. Frankfurt

Zoological Society, Cuc Phuong National Park Conservation Program, Fauna &

Flora International, Vietnam Program. Hanoi.

Wisconsin Primate Research Center, 30 October, 2002. Douc Langur (Pygathrix

nemaeus) (On-line). Accessed June 4, 2003 at

http://www.primate.wisc.edu/pin/factsheets/pygathrix_nemaeus.htm

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