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Anonymous. 2004. Status, Ecology and Conservation of Tigers in Peninsular Malaysia. Report: 1-54. Department of Wildlife and National Parks, DWNP), Wildlife Conservation Society - International Programme, (WCS).
Keywords: 4MY/camera-trapping/conservation/ecology/Panthera tigris/status/survey/tiger
Abstract: During 1997-2001 a national tiger conservation program was conducted by the Department of Wildlife and National Parks (DWNP) with the support of international conservation agencies Wildlife Conservation Society (WCS), WWF – Malaysia, and the University of Florida. The objectives of the programme were to assess the current conservation status of tigers in Peninsular Malaysia, study tiger ecology, use the results to make management recommendations, and develop staff capacity to manage tigers. This report covers fieldwork conducted by DWNP and WCS during 1997-1999. Nine sites were chosen for tiger survey across four states: Pahang, Trengganu, Kelantan and Perak. Eleven variables describing microhabitat structure were measured at each sampling location. Principal components analysis (PCA) was used to identify two major gradients in habitat disturbance and identify relatively disturbed sites (Lepar, Gunong Tebu, Ulu Temiang) from relatively less disturbed sites (Temenggor, Taman Negara, Bintang Hijau). Surveys involving 6,259 trapnights of sampling using 174 camera-trap setups revealed the presence of tiger and 38 other mammals, almost half of which were globally threatened species. Also recorded were twelve species of large reptile and bird including five globally threatened or near-threatened species. Ten individual tigers were recorded from 51 photographs at six of the nine sites. Tigers were detected at a quarter of all sampling locations (range=0- 2 48% per site), and at a frequency of 4.8±0.5 detections/100 trapnights (range=0-5.9 detections/100 trapnights per site). Activity patterns were inferred for tiger, other carnivores, and prey species from the time imprinted on photographs. Tigers showed a crepuscular pattern of activity and apparently avoided periods when human traffic was greatest. Human activity was recorded at all sites except for Bintang Hijau. Overall human traffic occurred across 20% of the sampling areas. Photographs from camera-traps were used to identify tiger individuals from their unique stripe patterns. The photographs were used to generate capture histories for tigers. These were used along with a capture-recapture approach to determine statistically the probability of capture for tigers and sample estimates of abundance at different sites. Coefficients of variation for abundance estimates ranged from 2 to 392% reflecting low numbers of recaptures. Tiger density was estimated from the sample abundance estimates and by assuming a sampling effective area for each site. This area was calculated by adding a buffer to the configuration of camera-traps equal to the absolute maximum movement distance (AMDM) of tigers. Tiger density varied from extremely low (2 tigers/100km2) at Temenggor. Despite intensive sampling, because the capture rates for tigers were low, and captures took place over a one-year period, extrapolating a statistical estimate of tiger abundance across Peninsular Malaysia is difficult at best. Nonetheless, population estimates for tigers were attempted for individual reserves, for Tiger Conservation Units (TCUs) and for all areas in Peninsular Malaysia by assessing (1) population density, (2) forest size and (3) a correction factor to take into account avoidance of habitat due to roads, powerlines, settlements and other human infrastructure. While these estimates are very rough indeed, they provide an estimate of the national population of 184-305 tigers, most of which occur in one Level I TCU (TCU#129; 173-257 tigers). This is less than half of the previous estimate for Peninsular Malaysia. 13. Tigers are threatened by a range of factors chiefly habitat loss and fragmentation, hunting of prey, commercial trade in live animals, dead animals and their parts, and harassment and displacement. Immediate action is needed to reduce these threats in the short-term (next five years) and to recover populations of wild tigers in Peninsular Malaysia in the longer-term (5-20 years from now
FINAL REPORT
Status, Ecology and Conservation of Tigers in Peninsular Malaysia
For
Department of Wildlife and National
Parks (DWNP)
By
Wildlife Conservation Society – International Programme
(WCS)
January 2004
ii
Table of Contents
1. Executive Summary of Findings 1 2. Recommended short-term actions 2 3. Recommended longer-term actions 3 4. Abstract 4 5. Introduction 5 6. Personnel 6 7. Study sites 7 8. Methods
a. Vegetation measurements 9 b. Sign based surveys versus camera-trapping 10 c. Survey objectives 11 d. Survey design - location of surveys 12 e. Sampling units – camera-traps 12 f. Location of camera-traps 12 g. Arrangement of camera-traps 13 h. Analysis 13 i. Relative abundance/activity 14 j. Absolute abundance 14 k. Activity patterns 15 l. Human impacts 15
9. Results a. Vegetation structure 15 b. Sampling efforts 17 c. Species richness 17 d. Tiger captures 19 e. Tiger abundance 19 f. Activity patterns 22 g. Human use 22
10. Discussion a. Significance of tigers 25 b. Tiger distribution 25 c. Tiger abundance 26 d. Relationship between index of abundance and density 26 e. Population size 27 f. Threats to tigers 29 g. Suggested priorities for tiger conservation 32
11. References 35 List of figures
1. Location of nine survey sites in Peninsular Malaysia (Dec ’97-Dec ’99) 8 2. Plot showing distribution of study sites along PC1 and PC2 axes. 17 3. Species accumulation curves for large mammals at nine sites in 18
Peninsular Malaysia. 4. Activity levels (%) of carnivores; (A) tigers and leopards (B),
clouded leopard/Asiatic golden cat, (C) Malayan sunbear/Dhole. 23 5. Activity levels (%) of tigers potential prey species;
(A) Common muntjak, Wild boar and mouse deer spp., (B) Sambar and Malayan tapir. 24
6. Activity levels (%) of tigers and humans. 24
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List of tables 1. Landscape context of nine tiger study sites 9 2. Component matrix showing loadings of 11 habitat structure
variables on four principal components. 16 3. Sampling effort for tiger survey at nine sites in Peninsular Malaysia. 18 4. Habitat use and relative abundance for tigers at nine sites. 19 5. Estimates for tiger abundance at sites in Peninsular Malaysia 21 6. Maximum distances moved and sample density estimates for tigers
at sites in Peninsular Malaysia 21 7. Human traffic at nine sites in Peninsular Malaysia. 25 8. Estimated numbers of tigers in reserves and TCUs in Peninsular Malaysia 29 9. Targets for tiger conservation with various time and spatial scales 34
Appendices
I. Site descriptions 40 II. Records from 174 camera-trap set-ups at nine sites in Peninsular Malaysia 45 III. List of reptiles, birds and mammals recorded by camera-trap survey at
nine sites in Peninsular Malaysia (December 1997-December 1999) 46 IV. Estimation of tiger abundance for sites where single tigers were caught 50
Cover photo; Tiger of Taman Negara National Park. Courtesy of Dr Kae Kawanishi
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Executive Summary of Findings
1. Malaysia is one of fourteen range countries for the Tiger (Panthera tigris) and extensive tracts of montane forests and fragmented lowland forests in Peninsular Malaysia form high potential habitat for the species. These same tiger areas are recognized as ecoregions of global importance for biodiversity conservation.
2. In the last two decades, tigers have become a species of increasing national
concern due to the conflicting issues of increasing frequency of livestock depredation and human injury, but also increasing concern over the conservation future of the species.
3. With increasing demands on public lands to support economic development,
habitats for tigers and other wildlife continue to be compromised. As part of Malaysia’s strategy of balancing development with conservation, there is an urgent need to incorporate tiger conservation into national development strategies.
4. The Tiger is a wide-ranging species with relatively large area requirements,
but also relatively high resilience to human disturbance. Therefore it is a useful indicator of ecosystem health since only where sufficient habitat, prey, and water occur can the Tiger survive. Also, in Malaysia, the Tiger is a nationally revered species that is Totally Protected by law. For these reasons it provides a convenient flagship and target species for monitoring.
5. During 1997-2001 a national tiger conservation program was conducted by the
Department of Wildlife and National Parks (DWNP) with the support of international conservation agencies Wildlife Conservation Society (WCS), WWF – Malaysia, and the University of Florida. The objectives of the programme were to assess the current conservation status of tigers in Peninsular Malaysia, study tiger ecology, use the results to make management recommendations, and develop staff capacity to manage tigers. This report covers fieldwork conducted by DWNP and WCS during 1997-1999.
6. Nine sites were chosen for tiger survey across four states: Pahang, Trengganu,
Kelantan and Perak. Eleven variables describing microhabitat structure were measured at each sampling location. Principal components analysis (PCA) was used to identify two major gradients in habitat disturbance and identify relatively disturbed sites (Lepar, Gunong Tebu, Ulu Temiang) from relatively less disturbed sites (Temenggor, Taman Negara, Bintang Hijau).
7. Surveys involving 6,259 trapnights of sampling using 174 camera-trap setups
revealed the presence of tiger and 38 other mammals, almost half of which were globally threatened species. Also recorded were twelve species of large reptile and bird including five globally threatened or near-threatened species.
8. Ten individual tigers were recorded from 51 photographs at six of the nine
sites. Tigers were detected at a quarter of all sampling locations (range=0-
2
48% per site), and at a frequency of 4.8±0.5 detections/100 trapnights (range=0-5.9 detections/100 trapnights per site).
9. Activity patterns were inferred for tiger, other carnivores, and prey species
from the time imprinted on photographs. Tigers showed a crepuscular pattern of activity and apparently avoided periods when human traffic was greatest. Human activity was recorded at all sites except for Bintang Hijau. Overall human traffic occurred across 20% of the sampling areas.
10. Photographs from camera-traps were used to identify tiger individuals from
their unique stripe patterns. The photographs were used to generate capture histories for tigers. These were used along with a capture-recapture approach to determine statistically the probability of capture for tigers and sample estimates of abundance at different sites. Coefficients of variation for abundance estimates ranged from 2 to 392% reflecting low numbers of recaptures.
11. Tiger density was estimated from the sample abundance estimates and by
assuming a sampling effective area for each site. This area was calculated by adding a buffer to the configuration of camera-traps equal to the absolute maximum movement distance (AMDM) of tigers. Tiger density varied from extremely low (2 tigers/100km2) at Temenggor.
12. Despite intensive sampling, because the capture rates for tigers were low, and
captures took place over a one-year period, extrapolating a statistical estimate of tiger abundance across Peninsular Malaysia is difficult at best. Nonetheless, population estimates for tigers were attempted for individual reserves, for Tiger Conservation Units (TCUs) and for all areas in Peninsular Malaysia by assessing (1) population density, (2) forest size and (3) a correction factor to take into account avoidance of habitat due to roads, powerlines, settlements and other human infrastructure. While these estimates are very rough indeed, they provide an estimate of the national population of 184-305 tigers, most of which occur in one Level I TCU (TCU#129; 173-257 tigers). This is less than half of the previous estimate for Peninsular Malaysia.
13. Tigers are threatened by a range of factors chiefly habitat loss and
fragmentation, hunting of prey, commercial trade in live animals, dead animals and their parts, and harassment and displacement. Immediate action is needed to reduce these threats in the short-term (next five years) and to recover populations of wild tigers in Peninsular Malaysia in the longer-term (5-20 years from now).
Recommended short-term actions 1. Ecological monitoring. Central to a recovery plan would be the establishment
of tiger and prey monitoring programs at key sites, landscapes and Level I and II TCUs, along with training to build research capacity for key staff. Monitoring would focus on existing breeding populations of female tigers. In addition, protected area databases need to be established, and staff assigned to
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manage the databases, so that data from research and monitoring activities may be used to detect population trends and made available for management planning.
2. Tiger protection. Monitoring programs would be combined with enforcement
training and the design of patrolling and anti-poaching systems to maintain and expand tiger populations at key priority sites. These programs would involve recruiting people in local communities who will provide information about who is poaching in the forest.
3. Trade research. Live and dead tigers from Peninsular Malaysia are potentially
traded across borders with neighbouring countries, especially those with relatively lax domestic laws and high demand. Better collaboration is needed between agencies concerned with enforcement to investigate and suppress this illegal trade.
Recommended longer-term actions 4. Creation of new protected areas. Only one area Taman Negara National Park
is large enough (>3,000km2) to support viable populations of tigers in the long-term. Many protected areas are smaller than 500km2. New protected areas need to be established in key tiger areas and existing areas increased in size.
5. Landscape-level planning for tigers. Tiger habitat throughout Asia is
continually being lost. Through use of a GIS database, the rate of habitat loss in Malaysia can be estimated, future loss may be projected and effects of creation of forest edges predicted. Identification of large blocks of habitat or potential habitat which are under threat is a potentially useful management tool, in particular since the loss of certain areas, such as the forest corridor between Taman Negara and Krau Wildlife Reserve, may have a negative impact on protected areas and the ability of tigers to move about the landscape.
6. Arresting habitat degradation. In some key sites habitat degradation is largely
a result of activities of local communities. Specific actions need to be taken to stabilize blocks of tiger current and potential tiger habitat.
7. Monitoring human-tiger conflicts. Information on tiger mortality must be
assembled to quantify the rate and reasons why tigers are getting killed in Peninsular Malaysia. This information can be used to increase awareness to garner support for conservation programmes.
8. Increasing public awareness. WCS and DWNP have assembled a considerable
amount of information and camera-trap photographs. These could be used creatively to increase public awareness and motivate field staff.
9. Tiger area management. Management Plans such as that developed for Krau
Wildlife Reserve need to be developed for other key tiger sites so that habitats may be protected and tiger populations recovered.
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10. Revising national tiger action plan. Information contained in this report together with separate reports on tiger ecology for Taman Negara provides the foundation for revising the National Tiger Action Plan.
Abstract
Across its global range the tiger is declining due to factors understood by researchers
and managers. However, effective management of tiger populations suffers from a
lack of information on their status and distribution. In Peninsular Malaysia, tigers are
a national emblem and Totally Protected species. Recognizing this importance and
their potential as an umbrella for the protection of forested landscapes and contained
wildlife, and the need for developing staff capacity for managing wildlife, the
Department of Wildlife and National Parks (DWNP) embarked on an ambitious
program to ascertain the health of tiger populations in representative habitats across
Peninsular Malaysia. From 1997-2001 surveys for tigers and other large mammals
were executed at twelve sites across four states, Perak, Terengganu, Kelantan and
Pahang. Camera-traps were the primary tool used in surveys. Surveys were jointly
designed and implemented by central and state level staff of DWNP, the Wildlife
Conservation Society, and the University of Florida, Gainesville. Results from
surveys at nine sites conducted between December 1997 and December 1999 are
reported here. Surveys revealed 39 species of mammals almost half of which were
globally threatened species. Tigers were confirmed from six sites in the Main Range
and Greater Taman Negara landscape, including multiple locations inside a Level I
Tiger Conservation Unit (TCU#129), inside Level II TCU#130, and near other Level
II and III TCUs. Tiger abundance was estimated using photographic records of tiger
individuals, capture–recapture statistical analysis, and a sample area defined based on
the maximum distance that individual tigers move during the sample period. The tiger
population for Peninsular Malaysia is conservatively estimated as 235 (range=184-
305). Key threats facing tigers are habitat loss and fragmentation, hunting of prey,
commercial tiger trade and harassment and displacement. A framework for
organizing priority targets for tiger conservation is described.
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Introduction
One hundred years ago when Peninsular Malaysia was extensively covered with
forest, tigers were hunted regularly for sport (Wallace 1869; Whitney 1905). The
combination of this plus loss of habitat meant that by the early 1950’s tigers had
disappeared from Penang (Locke 1952), and later from Melaka and Perlis. Up until
1976 the Indochinese tiger was considered a pest, with hunting combining with loss
of habitat to cause serious declines in Peninsular Malaysia (Blanchard 1977). After
1976, the tiger became a totally protected species (Samsudin & Elagupillay 1994). In
spite of this change in legal status, little was known about the status of wild
Indochinese tiger in Peninsular Malaysia (Elagupillay & Wan Shahruddin 1999;
Topani 1990). While surveys revealed tigers in some places (Ratnam et al. 1995)
until the end of the last century most information was derived from unconfirmed
reports (Rabinowitz 1999).
To plan for the future conservation of tigers, knowledge of their current status and
threats is required. In the late 1990’s an attempt was made to identify potentially
viable tiger habitat across the tiger’s entire range across Asia. Natural vegetation was
divided into three grades of tiger habitat, using current available information on
habitat integrity, poaching pressure and population status (Dinerstein et al. 1997).
These graded habitats are known as Level 1, or Level 2 or Level 3 Tiger
Conservation Units (TCUs). Level 1 TCUs are thought to offer the highest probability
of persistence of tiger populations over the long-term (Dinerstein et al. 1997). One
Level 1 TCU (#129) was described for Peninsular Malaysia. It covers the northern
part of the Peninsular and encompasses parts of Kedah, Perak, Selangor, Kelantan,
Terengganu and Pahang, and includes Taman Negara and the forested part of
southern Thailand, a total of 27,469km2 of potential tiger habitat. Two Level 2 TCUs
(2,472km2) and 13 Level 3 TCUs (4,344 km2) were also identified in the Peninsular.
A striking feature of this ‘framework analysis’ was that for Peninsular Malaysia, and
some other countries in Mainland Southeast Asia, there existed large gaps inside the
TCUs for which no recent information on tiger status was available. Added to this
was the fact that most records of tigers compiled by the Malaysian Department of
Wildlife and National Parks (DWNP) came from forest-farmland interfaces
(Elagupillay et al. 2001) and at least some of these were unconfirmed reports
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(Rabinowitz 1999). This reflects the historical priorities for tiger management which
focussed on human-tiger conflict resolution (DWNP 1992; Elagupillay 1983, 1984;
Elagupillay et al. 2001; Elagupillay & Wan Shahruddin 1999; Jasmi 1986; Jasmi &
Wan Shahruddin 1998; Khan 1987; Kitchener 1961; Samsudin & Elagupillay. 1994;
Topani 1990) and the need for staff training in tiger survey methods.
Recognizing the paucity of information on tigers from areas inside forest reserves,
and at the same time desiring to mitigate the effects on tiger survival of future
intrusions into these habitats by national development programmes, the DWNP
embarked on an ambitious programme with partners Wildlife Conservation Society,
the University of Florida, Gainesville, and WWF Malaysia. The programme had
three broad goals:
1. To determine the distribution and status of tigers throughout Peninsular
Malaysia.
2. To collect information on tiger numbers, movements, behaviour, home range
size and habitat use in a key tiger site identified from the survey programme.
3. To transfer technology and train Malaysian wildlife biologists in techniques
for surveying and studying tigers to allow for the future management and
conservation of tiger populations.
This report details the findings of a field survey and training programme conducted by
DWNP with support from the Wildlife Conservation Society from December 1997 to
December 1999. Recommendations for future research and management action are
provided. Results of an ecological study mounted by the University of Florida,
Gainesville are reported elsewhere (Kawanishi 2002; Kawanishi et al. 1999) but are
referenced in this report. Together, these two studies provide current baseline
information on the status, distribution and threats facing tigers in Peninsular Malaysia,
and provide a basis for updating the Malaysia Tiger Action Plan (DWNP 1995).
Personnel
The lead agency for the program was the DWNP. All work was done in full
collaboration with DWNP. The tiger programme was implemented for DWNP by;
1. En. Musa Nordin, Director-General
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2. En. Sahir Othman, Director of Research and Wildlife Conservation
3. En. Sivananthan Elagupillay, Head of Wildlife Management Unit
4. En. Jasmi Abdul, Director of Perak and local staff
5. En. Mohd. Shamsuddin Saari, Director of Terengganu and local staff
6. En. Rahim Ahmad, Director of Kelantan and local staff
7. Mr Wan Shaharuddin Wan Noordin, Tiger Coordinator
At the time the project was commenced, DWNP lacked sufficient trained staff to
conduct tiger survey. Thus during the two year project, three foreign experts were
recruited to assist with training and data collection;
1. Dr Ruth Laidlaw. Responsible for direct field supervision of surveys in target
areas, and for detailed training of DWNP staff in tiger and prey survey
techniques e.g. rapid survey techniques, camera-trapping, data recording and
management, and assimilation of information into a database.
2. Ms Kae Kawanishi. Conducted an ecological study of tigers at Taman
Negara and trained DWNP staff in ecological study methods, e.g., camera-
trapping, collection, management and analysis of data.
3. Dr Antony Lynam. Jointly responsible, with Dr Laidlaw, for overall project
design and initial training of DWNP staff. He provided advice on survey
implementation during the programme, assembled and analyzed data, and
compiled this final report.
In addition to project personnel, Drs Elizabeth Bennett, Joshua Ginsberg, and
Timothy O’Brien provided expert comments on earlier drafts of this report.
Study Sites
In this study, tiger surveys were conducted in forest blocks with greatest potential for
conserving tigers in the long term (DWNP unpublished data; Dinerstein et al. 1997;
(Wikramanayake et al. 2002). Surveys were completed in a total of nine sampling
plots in Perak, Terengannu, Kelantan and Pahang (Fig. 1). Descriptions of the sites
are given in Appendix I. Seven sites were located inside Level 1 TCU (#129), one in
Level II TCU (#130) and one adjacent to Level II TCU (#134) to determine in which
parts of these potential habitat tigers persist and why. These sites were chosen since
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such knowledge is critical in allowing DWNP to take appropriate action to conserve
tigers. The information would also provide invaluable baseline data for future
monitoring.
Fig. 1. Location of nine tiger survey sites in Peninsular Malaysia (Dec ’97-Dec ’99).
Within the TCUs, study sites were selected to cover a range of different forest types
and management histories, e,g. riverine forest, lowland, hill and montane forest;
logged and unlogged forest; protected forest and forest reserves; forest fragments,
edge forest and core forest and tiger-human conflict zones and non-conflict zones
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(Table 1). One site was located inside a protected area, Taman Negara National Park.
Totally protected areas (national parks and wildlife reserves) constitute approximately
5.7% of the land area in Peninsular Malaysia. All other sites were in Forest Reserves.
Table 1. Landscape context of nine tiger study sites (see also Appendix I).
Study site Location Area Logging history
Temenggor central * continuous unlogged
Bintang Hijau central >1,400 km2 **unlogged/logged
Jengai central * continuous **unlogged/logged
Gunung Tebu edge * continuous **unlogged/logged
Ulu Temiang edge
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4. DISTANCE MEDIUM TREE - Average distance to nearest tree < 30 cm gbh
and >1.3 m in height, measured in four quadrants at the point
5. CIRCUMFERENCE MEDIUM TREE - Average circumference of nearest
tree < 30 cm gbh and > 1.3 m height, measured in four quadrants at the point
6. UNDERSTORY 5m - Median understory density at 5m (scored out of 10,
with 1 = very poor visibility), measured in four quadrants at the point
7. UNDERSTORY 10m - Median understory density at 10m (scored out of 10;
with 1 = very poor visibility), measured in four quadrants at the point
8. WOODY CLIMBERS – Number of woody climbers ≥ 3cm diametre within
20m (scored out of 4)
9. BAMBOO – Number of bamboo clumps within 20m (scored out of 4)
10. RATTAN – Number of rattans ≥ 2cm diametre within 20m (scored out of 4)
11. PALM – Number of palms ≥1.3m height within 20m (scored out of 4)
Principal components analysis (Pielou 1984; Tabachnick & Fidell 1983) was used to
identify independent patterns of covariation among the habitat structure variables.
PCA constructs new, synthetic variables that are linear combinations of the raw
variables. Each sampling point can be scored on each PCA axis based upon the values
of its raw variables.
Sign based surveys versus camera-trapping
The Indochinese tiger occurs at low densities and is difficult to detect in the humid
forest conditions of Peninsular Malaysia (Elagupillay & Wan Shahruddin 1999) and
forest habitats elsewhere in its range (Duckworth and Hedges 1998; Rabinowitz
1993). Until recently, sign counting was the most commonly used and readily
available method for assessing tigers in Malaysia (Topani 1990). However, tiger
census using indirect sign alone can be fraught with difficulties as it depends on the
substrate, the skill of the tracker, and the long-term knowledge of an area and of the
tigers within (McDougal 1999). Furthermore, tiger tracks are seldom visible on
substrates covered with leaf litter, they can be difficult to distinguish from leopard
tracks and it is rarely possible under these conditions to distinguish one individual
tiger from another by using tracks. Countrywide total censuses using tiger tracks
were first introduced in India in the 1970’s (Panwar 1979; Karanth 1987). The
methods used (pug-mark identification) have since been tested and proved not to be
11
valid (Karanth 1987, 1995; Karanth & Nichols 1998; Karanth et al. 2003). In
addition, surveying using other animal signs is problematic. For example, prey
carcasses and scats decompose rapidly in hot, humid conditions and can also be
difficult to distinguish from those of leopards (Duckworth and Hedges 1998;
Elagupillay & Eh Pat 1997).
A more reliable method both for detecting tigers and estimating their abundance
involves the use of remote camera-photography (Cutler & Swann. 1999). For
example, camera-traps have been used to establish tiger presence-absence (Griffiths &
Schaik 1993a). Each tiger has its own unique coat pattern (Schaller 1967) thus
permitting their individual identification (Franklin et al. 1999). Thus camera-traps
can be used for estimating tiger relative abundance (Lynam et al. 2001) and absolute
abundance (Karanth 1995; Karanth and Nichols 1998; O'Brien et al. 2003). Although
there are relatively high initial costs of investment involved in camera-trapping it
appears to be the most appropriate technique for large cat inventory over a wide range
of environmental conditions (Silveira et al. in press).
Survey objectives
Field managers desire to know several important pieces of information about tigers;
(1) the distribution of tigers and prey species across a reserve or region, (2) how tiger
abundance compares between areas where they are present, and (3) information on
specific threats to tigers, and how to mitigate those threats. In this study we addressed
the first objective by determining the pattern of presence or absence of tigers and
other large mammals at sampling points inside representative habitats. A second
objective was to compare the frequency of use of different habitats between sites, and
also to achieve sample estimates of tiger numbers for areas of forest at each site.
Finally, information on threats to tigers was gleaned from records of human intrusions
at each site via camera-trap records and other field observations. This information
was supplemented by general appraisals of habitat suitability from other studies
(Laidlaw 2000; Kawanishi 2002).
Survey design - location of surveys
Since 1976, the DWNP Tiger Research Unit has collected information on tigers from
field observations of researchers and other staff, and via reports by farmers and other
12
local people. The latter reports were associated with occurrences of livestock
depredation or attacks on humans. While this has provided valuable information on
tiger occurrence, the collection of field data was done in response to calls from the
public and was non-systematic in its coverage. In the current study, DWNP staff and
local people were interviewed to determine potential tiger areas in each State.
Selection of survey sites was therefore non-random but based on the best available
information.
Sampling units – camera-traps
Data were collected using camera-traps as they can provide non-invasive unbiased
information on animal movements, activity patterns (van Schaik & Griffiths 1996)
and abundance (Karanth 1995). The camera-trap devices used (CamTrak South Inc.
Georgia, U.S.A.) consisted of a weatherproof Infinity Mini DLX Olympus camera
with a 35mm lens and flash, and a passive infrared sensor, all housed in a waterproof
casing. The cameras are triggered when the sensor detects a differential in heat and
motion across a conical beam in front of the camera-trap, and a photograph is taken.
The cameras included a databack and could be programmed to record date and time
(24 hour clock) on the film (Fig. 2). Fuji 400ASA, 36 exposure film was used with the
camera-traps. A heavy-duty cycle lock was used to secure each trap to a tree. In most
cases this prevented theft. The cameras were programmed with a 3-minute time delay
so that animals lingering in front of the camera for short periods of time would not
cause the camera to take an entire roll of film.
Location of camera-traps
Camera-traps were placed to maximize the probability of detection (p) for tigers
(Karanth and Nichols 1998, 2002). Camera-traps were set at ‘optimal’ locations on
animal trails and roads, and mounted 40cm above the ground, and 3-5m (the focal
length of the camera) from the middle of the trail. Locations for traps were places
where either tiger sign, or sign of tiger prey species was detected. Surveys were
constrained by remoteness with most sites accessible only on foot. Traps could not be
checked on a daily basis and were left in the forest for 30-35 days set for operation
day and night. One “trap-night” in this paper, therefore, refers to one 24 hr period
(Kawanishi et al. 1999). Information on details of camera-trap setup and retrieval
were recorded on a standardized datasheet and the number of trap-nights over which a
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trap was functional was determined. Surveys were conducted from December 1997 to
December 1999 inclusive.
Arrangement of camera-traps
At each study site, thirty camera-traps were established at 25 ‘optimal’ locations on a
10 x 4 km grid. Each grid was divided into 40 subunits of 1 km2. At twenty alternate
1 km2 grids, single camera-traps were positioned at ‘optimal’ locations. At five
opportunistic locations, usually places where tiger sign was detected, at junctions of
trails, trails on ridgelines or water-crossings, or on saddles between hills, pairs of
traps were positioned on opposite sides of the trail/road in "check-points". Check-
points allowed the identification of individual tigers by allowing both sides of an
animal to be photographed simultaneously. Field crews attempted to distribute the
“check-point” pairs across the grid to achieve maximum coverage. Additional details
on procedures for selecting camera-traps, and deployment of traps are given in
(Laidlaw 1998).
Analysis
Films retrieved from traps were processed and information on time, date and species
recorded from each frame was entered into a database and summary information
extracted onto a standardized datasheet (see also Kawanishi et al. 1999). Independent
events or ‘detections’ were defined as (1) consecutive photographs of different
individuals of the same species, (2) consecutive photographs of individuals of the
same species taken more than 0.167 hrs apart. Sometimes, the time record on certain
photographs was illegible. This was due to flash overexposure in the corner of the
photograph where the time was marked. Occasionally, also, the time was not printed
on the photograph. This was largely due to human error setting up and programming
the camera. These photographs without inscribed times, were not used in our
analyses.
Relative abundance/activity
For each species, two relative abundance/activity indices (RAI) were calculated and
follows O’Brien et al. (2003);
14
1. RAI1 = number of days from the start of trapping to the first record of a tiger.
This measured the effort required to record a tiger from survey and should
decrease with increasing population density (Carbone et al. 2001).
2. RAI2 = number of detections divided by the number of trap-nights during
which the trap was functional at a location. This is the reverse of RAI1 and
should increase with population density. RAI2 was scaled to detections per
100 trapnights.
Absolute abundance
Photos of tigers from camera-traps and capture-recapture statistical models were used
to obtain sample estimates of tiger density at each study site (Karanth 1995; Karanth
and Nicols 1998). The procedures followed the recommendations of Karanth and
Nichols (2002) and were analyzed using Program CAPTURE (Otis et al. 1978;
Rexstad & Burnham. 1991; White et al. 1982). CAPTURE assumes that populations
are ‘closed’, i.e., that there are no gains or losses of individuals e.g from births,
deaths, immigration or emigration during the surveys. Since most sampling locations
employed only one camera-trap, so photos from only one side of an animal were
available, analyses were done using either right side or left side photos only. This
lowers capture probability (p) but it is still possible to use the method for estimation
(Karanth 1995; J.D. Nichols pers. comm.).
Data analysis was done as follows;
1. individual tigers were identified from photographs and given unique codes
2. a capture history – a row of ‘0’s and ‘1’s - was developed for each coded
animal with ‘0’s indicating no detection (no photograph) or ’1’ indicating
detection (photograph taken) for a given sampling interval i.
3. each sampling interval was a group of 3 trapnights. Up to a maximum of 17
sampling intervals were used at each of the nine study sites
4. following Karanth and Nichols (1998), Model Mh was used to model capture
probability. This model allows for variability in capture probability among
individuals since tigers in different age classes i.e., cubs, juveniles, transients
and adults, might have different capture probabilities due to different
movement behaviour (Karanth and Nichols 2002). It also assumes that an
individual tiger’s capture probability stays unchanged during the survey.
15
Activity patterns
To assess the ecological overlap or separation of carnivores and prey, activity budgets
were compared among species using camera-trap photographs imprinted with times.
Patterns of activity were represented by frequency histograms with time divided into
hourly intervals.
Human impacts
Human activity can have significant impacts on tigers and other wildlife (Griffiths &
Schaik 1993b). In order to document this for each site, human traffic was measured
as number of photographs of humans/100 camera-trapnights (i.e. RAI2), and human
activity patterns were compared with those of tigers.
Results
Vegetation structure
The 11 habitat structure variables were measured at 151 points where camera-traps
were established. These variables can be summarized by 4 composite principal
components variables (Table 2). The four composite variables explained 65% of the
variation in the dataset. The loadings for each variable described what each of the
four new variables described in terms of gradients in vegetation structure:
1. PC1. This variable described a disturbance gradient with increasing canopy
cover and decreasing distance to large trees (i.e. increasing closure of forest),
decreasing distance of medium-size trees (increasing density of understory),
and increasing density of woody climbers and palms.
2. PC2. This variable also described a disturbance gradient of increasing
visibility of understory vegetation and decreasing density of medium-sized
trees (i.e. increasing openness of understory).
3. PC3. This variable described a gradient of increasing size of medium-sized
trees and increasing density of rattan.
4. PC4. This variable described a gradient of increasing density of bamboo.
Principal components can be used to distinguish sites along the continuum from least
disturbed to most disturbed. When mean values for PC1 and PC2 were plotted on two
axes, sites that were least disturbed (Temenggor, Taman Negara, Bintang Hijau) were
16
identified from more disturbed sites (Gunong Tebu, Lepar and Ulu Temiang)(Fig. 2).
Other sites (Jengai, Ayer Ngah) lie in between these two sets of points.
Table 2. Component matrix showing loadings of 11 habitat structure variables on four principal components. Significant principal components have eigenvalues >1.0. Bold denotes factor loadings >0.5. These variables described the gradients represented by the principal components.
Components Variable measured
PCA1 PCA2 PCA3 PCA4
CANOPY COVER -.850 .094 **** .006
DISTANCE LARGE TREE -.812 .236 .264 .175
CIRCUM LARGE TREE .319 -.154 -.279 .326
DISTANCE MEDIUM TREE -.525 .595 .239 .119
CIRCUM MEDIUM TREE -.339 -.455 .583 .0019
UNDERSTORY 5m .459 .635 -.298 ****
UNDERSTORY 10m .280 .578 .287 -.286
WOODY CLIMBERS .743 .041 .324 ****
BAMBOO .128 .152 **** .873
RATTAN .453 .082 .655 .180
PALM .674 **** .199 .101
Eigenvalue 3.4 1.4 1.3 1.0
% variance explained 30.8 13.0 11.7 9.5
Cumulative variance explained 30.8 43.8 55.5 65.0
17
-0.5
-0.4
-0.3
-0.2
-0.1
0
0.1
0.2
0.3
0.4
0.5
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
More disturbance - PC1 - Less disturbance
Fig. 2. Plot showing distribution of study sites along PC1 and PC2 axes. These axes describe gradients in forest disturbance. One site (Cameron Highlands) could not be
portrayed because of missing habitat data.
Sampling efforts
A total of 174 camera-trap units were deployed at the 151 sampling locations during
the surveys. These units recorded a total of 2,979 photographs from 6,259 trapnights,
at the nine study sites (Table 3, Appendix II). The overall rate for camera-trapping
was, therefore, roughly one photograph taken every three days. When test
photographs (taken during setup or takedown) were excluded, camera-traps failed at a
rate of 6% (Appendix II).
Species richness
Tigers and 38 other species of mammals, as well as humans were recorded by camera-
traps at the nine sites (Appendix III). Almost half of the mammals (16 species) are
globally threatened or data deficient species (Hilton-Taylor 2000), and two are near
threatened species. Twelve were CITES listed species, 5 of them Appendix I species.
Because sampling efforts varied between sites, large mammal richness cannot be
compared directly. Also species numbers did not asymptote at any site during the
periods of sampling (Fig. 3). However, the rates of species accumulation were
relatively higher at three sites (Ulu Temiang, Gunong Tebu and Lepar), relatively
medium at three sites (Ayer Ngah, Temenggor and Taman Negara), and relatively
lower at three sites (Bintang Hijau, Jengai and Cameron Highlands).
Jengai
Taman Negara
Temenggor
Bintang HijauAyer Ngah
Ulu Temiang
Gunong Tebu
Lepar
18
0
2
4
6
8
10
12
14
16
18
1 4 7 10 13 16 19 22 25 28 31 34 37
Time (days)
Ayer NgahBintang HijauCameron HighlandsGunong TebuJengaiLeparTemenggorTaman NegaraUlu Temiang
Fig. 3. Species accumulation curves for large mammals at nine sites in
Peninsular Malaysia.
Camera-traps also recorded 12 species of reptiles and birds. Three birds are globally
threatened and two are near threatened species. Six species were CITES Appendix II
or III species.
Table 3. Sampling effort for tiger survey at nine sites in Peninsular Malaysia.
Site Start End # tigers
(recaps) Camera-trap
setups
Trap
nights
1. Temenggor 10.12.97 2.3.98 2(4) 22 785
2. Bintang Hijau 12.2.98 26.3.98 2(4) 19 646
3. Jengai 28.4.98 4.6.98 0 15 467
4. Gunong Tebu 26.6.98 27.8.98 1(11) 27 807
5. Ulu Temiang 30.8.98 30.9.98 3(11) 21 557
6. Ayer Ngah 9.10.98 13.11.98 1 18 562
7. Cameron Highlands 7.2.99 22.3.99 0 13 495
8. Taman Negara 26.5.99 14.8.99 0 16 768
9. Lepar 28.9.99 23.12.99 1(4) 23 1172
Totals 10(34) 174 6,259
19
Tiger captures
A total of 51 photographs of ten individual tigers were taken at 36 sampling locations
across the nine sites. Tigers were recorded at a quarter of all locations (Table 4) or, at
each site, at 18 ± 6% of sampling locations. Tigers were not recorded at Taman
Negara, Cameron Highlands and Jengai but occurred at almost half of the locations at
Ulu Temiang. On average one tiger photograph was taken for every 122 trapnights of
sampling. Average RAI1 at locations where tigers were detected was just over 15
trapnights/first capture (Table 4). Overall RAI2 was 0.82 photographs/100 trapnights,
with average per point RAI2 less than 5 photographs/100 trapnights.
Table 4. Habitat use and relative abundance for tigers at nine sites.
Site %
locations detected a
RAI1b
( x ± SE)(n)
RAI2 c
( x ± SE)(n)
1. Gunong Tebu 26 9.1±3.2 (7) 5.9±0.6 (7)
2. Ulu Temiang 48 11.8±2.6 (10) 5.7±0.9 (10)
3. Bintang Hijau 32 12.7±2.4 (6) 5.3±1.9 (6)
4. Temenggor 16 12.4±3.3 (5) 4.3±0.6 (5)
5. Ayer Ngah 6 7 (1) 3.1 (1)
6. Lepar 26 37.8±6.2 (6) 2.3±0.3 (6)
7. Cameron Highlands 0
8. Taman Negara 0
9. Jengai 0
All sites 25 15.8 ± 2.3 (34) 4.8 ± 0.5 (34) a Naïve estimate of occupancy i.e. no. locations detected/total no. locations. b Mean/standard error (number of locations) days to first capture (number of locations). c Mean/standard error (number of locations) number of detections/100 trapnights.
Tiger abundance
Between 1 and 3 individual tigers were detected at six sites. For sites where
recaptures of tigers were made, Program CAPTURE was used to obtain sample
abundance estimates for tigers. Captures/recaptures were divided into 11 to 20
sampling occasions for analysis. Tigers were detected with a range of probability
values (Table 5) indicating possible differences between sites. Estimates of tiger
numbers had wide variance reflecting low numbers of recaptures at sites (Table 5).
20
For sites where only single tigers were recorded Program CAPTURE could not
calculate a detection probability ( ˆ p ) or SE for ˆ N . To estimate tiger density, these
parameters were first derived using a method described in Appendix IV.
Three northern sites (Temenggor, Ulu Temiang, and Gunong Tebu) that are part of
the Northern Forest Complex were all sampled within a 10 months period (Table 3;
December 1997-September 1998). During the same period, an estimate of tiger
density was made using the same method across the border in contiguous forest at a
site inside Thailand’s Halabala Forest Complex (Bang Lang National Park). If it is
assumed that the populations were demographically closed during this time (i.e., no
births, deaths, or movements in and out), then combining the recaptures of tigers from
these sites gives a sample estimate for tiger abundance for the transboundary northern
Peninsular Malaysia/southern Thailand forest complex. Because these estimates
assume a closed model for estimation, and we assume the population was indeed
closed over the timeframe analyzed, the results are indicative but not definitive.
Mean sample density ˆ D and range of density values at each site were calculated using
the sample estimates of tiger numbers ˆ N and by assuming a sampling effective area ˆ A at each site. Translation of the abundance estimate into density was done by:
ˆ D ' =ˆ N '
ˆ A (W ) ,
where )(ˆ WA is the sampling area with buffer width W. )(ˆ WA was calculated by
linking the outermost locations of camera-traps and adding a buffer with radius W
equivalent to half the absolute maximum distance moved (AMDM) between
recaptures for individual tigers (Wilson & Anderson. 1985; Kawanishi 2002) For
example, at the Bintang Hijau site, two tigers were captured and recaptured by
camera-traps. One female tiger ranged a maximum 9.75km between successive
points of capture/recapture. A male tiger ranged a maximum 5.25km between
locations. Buffer width (W) was then equal to 9.75km. The area of the plot plus
buffer was then (4 + 9.75km) x (10 + 9.75km) = 272km2 (Table 6).
21
Table 5. Estimates for tiger abundance at sites in Peninsular Malaysia*.
Site T Mt+1 p a ˆ N (SE) b CI CV (%)
1. Temenggor 12 2 0.0833 3(1.38) 3-9 46
2. Ulu Temiang 11 3 0.333 3(0.05) 3-3 2
3. Gunong Tebu 11 1 1
4. Bintang Hijau 14 2 0.1429 2(7.85) 2-2 392
5. Ayer Ngah 12 1 1
6. Lepar 20 1 1
Northern sites (1-3) 11 6 0.2468 7(1.38) 7-13 20
Halabala (Thailand) 8 3 0.2812 4(1.35) 4-10 34
Northern sites +
Halabala
11 9 0.2314 11(1.96) 10-19 18
* T=number of sampling occasions; Mt+1 = Number of animals captures; CI=95% confidence interval of estimate; CV (%)= coefficient of variation; a Detection probability estimated using Program CAPTURE; b Single sided M-R estimates using Program CAPTURE
Table 6. Maximum distances moved and sample density estimates for tigers at sites in Peninsular Malaysia.
Site Plot
size
(km2)
AMDM
a (km) )(ˆ WA ˆ D b ˆ D min -
ˆ D max
1. Temenggor 40 4.0 112 2.68 1.44-3.92
2. Ulu Temiang 40 8.2 154 d 1.95 1.92-1.98
3. Gunong Tebu 40 7.0 188 0.60 e 0.45-0.75
4. Bintang Hijau 40 9.8 272 0.74 0-3.63
5. Ayer Ngah 40 7.0 c 188 0.60 d 0.45-0.75
6. Lepar 40 7.3 195 0.58 d 0.43-0.72
Northern sites (1-3) 120 8.2 368 1.90 1.53-2.28
Halabala (Thailand) 40 10.5 297 1.35 0.89-1.80
Northern sites +
Halabala
160 10.5 543 2.02 1.66-2.39
a AMDM=Absolute maximum movement distance; b Sample estimate of tiger density; no. tigers/100km2; buffer width=AMDM/2; c No recaptures at this site, assumed same AMDM as Gunong Tebu (nearest site); d Calculated sampling area was larger than size of the reserve so the latter was used to estimate density; e No recaptures or single individuals. Density (D) = No. tigers (N) /Area, where N = No. tigers detected/p, and p=0.888 (p calculated from entire Malaysia study - Appendix IV).
22
Sample density estimates ranged from 0.58-0.60 tigers/100km2 at Lepar, Gunong
Tebu and Ayer Ngah to 2.68 tigers/100km2 at Temenggor (Table 6). A sample
estimate for tiger density in the northern Peninsular region was 1.90 tigers/100km2
(Range=1.53-2.28). If the northern Malaysia sites and Halabala, Thailand are
combined, an estimate of tiger density for the transboundary forest complex that
comprises TCU#129 was 2.02 tigers/100km2 (Range=1.66-2.39).
Activity patterns
Camera-trap photographs revealed that tigers were active at all times of the day and
night but had bi-modal peaks of activity from 06:00-11:00hrs and 17:00-21:00hrs
(Fig. 4 A). This crepuscular pattern was significant (P
23
0
5
10
15
20
25
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Tiger
Leopard
A
0
2
4
6
8
10
12
14
16
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Clouded leopard
Golden cat
B
0
5
10
15
20
25
30
35
40
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Sun bear
Dhole
C
Fig. 4. Activity levels (%) of carnivores; (A) tigers and leopards (B), clouded leopard and Asiatic golden cat, and (C) Malayan sunbear and Dhole.
24
0
2
4
6
8
10
12
14
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Muntjac
Wild boar
Mouse deer
A
0
5
10
15
20
25
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Sambar
Tapir
B
Fig. 5. Activity levels (%) of tigers potential prey species; (A) Common muntjak, Wild boar and mouse deer spp., (B) Sambar and Malayan tapir.
0
5
10
15
20
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
Hour
Tiger
Human
Fig. 6. Activity levels (%) of tigers and humans.
25
Table 7. Human traffic at nine sites in Peninsular Malaysia.
Site %
locations detected a
% total traffic b
RAI2 c
( x ± SE)(n)
1. Gunong Tebu 26 6 28.7±23.4(7)
2. Ulu Temiang 33 6 37.4±26.6(7)
3. Bintang Hijau 0 0 0
4. Temenggor 23 4 14.4±10.5(5)
5. Ayer Ngah 33 8 45.9±15.9(6)
6. Lepar 22 3 21.2±14.5(5)
7. Cameron Highlands 8 3 52.6±47.4(2)
8. Taman Negara 12 2 2.4±2.4(2)
9. Jengai 1 4 55.9±31.4(2)
All sites 20 4 25.6±4.6(36) a Naïve estimate of occupancy i.e. no. locations detected/total no. locations. b No. human photographs x 100/total no. photographs. c Mean/standard error (no. locations) no. detections/100 trapnights.
Discussion
Significance of tigers
The tiger is a critically endangered species whose range has contracted to 95% of its
original extent in the past century (Dinerstein et al. 1997; Kawanishi 2002; Nowell &
Jackson 1996). Tigers have large area requirements and are particularly sensitive to
habitat fragmentation and edge effects (Woodroffe & Ginsberg 1998) including those
induced by roads (Miquelle et al. 1999). The tiger is therefore an indicator of
ecosystems in crisis (J. Seidensticker in Ginsberg 2001) especially since their absence
can potentially lead to the collapse of mammalian food chains (Seidensticker 2002).
As Asian landscapes become ever-more developed to accommodate humans, the tiger
will help us to monitor the impacts on wildlife and wilderness.
Tiger distribution
In this study, surveys across nine forest areas revealed the presence of tigers in
multiple parts of a Level I TCU (#129: Temenggor, Ayer Ngah, Gunong Tebu, Ulu
Temiang) as well as one Level II TCU (#130: Bintang Hijau) and adjacent to one
26
Level III TCU (#134: Lepar). Tigers were not detected at three sites, specifically a
site in the Cameron Highlands, Ulu Sat in the eastern part of Taman Negara, and
Jengai which lies to the southeast of Taman Negara. In contrast Kawanishi (2002)
found tigers to occur the central and western parts of Taman Negara National Park at
Merapoh, Kuala Terengan, and Kuala Koh.
Between sites the probability of detecting tigers ranged an order of magnitude (Table
4). Within sites, tigers were also evenly detected across survey plots and on average
occurred at around 25% of sampling locations (Table 4). That tigers were not
consistently found across available habitat suggests that factors that vary both within
and between sites influence their distribution. Clearly such factors need to be
identified and their effects understood in order to effectively manage tigers across
sites and landscapes.
Tiger abundance
In parts of its range in South Asia, tiger populations have been intensively surveyed in
open grasslands and deciduous forest habitats (Karanth 1995; Karanth and Nichols
1998; Karanth and Nichols 2000). However, few estimates of tiger abundance exist
for rainforest habitats where the species is difficult to see. In Bukit Berisan Selatan
National Park, Sumatra tigers occur at a density of 1.6 tigers/100 km2 (95% CI=1.2-
3.2) at (O’Brien et al. 2003). In Taman Negara, tigers ranged in density from 1.10
tigers/100km2 (95% CI=1.1-4.4) to 1.98 tigers/100km2 (95% CI=1.7-4.0)(Kawanishi
2002). In Thailand’s Halabala Forest Complex, contiguous with Malaysia’s northern
forest complex, tigers ranged in density from 1.2 tigers/100km2, to 1.4 tigers/100km2
(95% CI=1.3-3.4) (Table 4; Lynam unpublished data). At Kaeng Krachan, a
rainforest site in Peninsular Thailand, tigers occurred at slightly higher densities 3.5
tigers/100km2 (95% CI=3.5-9.2)(Lynam unpublished data). At Badhra, India also an
evergreen forest site, tigers occurred at similar density to Kaeng Krachan i.e. 3.4 ± 0.8
tigers/100km2 (Karanth and Nichols 2000).
Relationship between index of relative abundance and tiger density
Of particular interest to conservation managers is the relationship between the
accumulation rate of tiger photographs from camera-trapping and tiger density
(Carbone et al. 2001; O’Brien et al. 2003). If a monotonic relationship exists between
27
the two variables, then an abundance index could be used to infer density. Using data
from six sites where tiger density could be estimated, a regression of RAI1 with
Ln(density) was non-significant (r2=0.05, p>0.05). Therefore, for this particular
dataset, the number of photos does not provide a reliable density index.
Population size
Population estimates based on mark-recapture data have been made for large cats in
reserves similar in size to Taman Negara (tigers in Indonesia: O’Brien et al. 2003;
tigers in Myanmar: Myanmar Forest Department 2003) and reserves that approximate
the size of all potential tiger habitat in Peninsular Malaysia (Maffei et al. 2003; Silver
et al. submitted). In each of these studies survey efforts were similar to or less than
those in this study, and the study of Kawanishi (2002). This suggests the possibility
for meaningful population estimates of tigers in Malaysian forests.
Recent estimates of tiger numbers in Peninsular Malaysia have apparently increased
over time: from 250 in the early 1980’s (Khan et al. 1983), then fluctuating between
500 (Topani 1990) and 600-650 (Khan 1987; Samsudin & Elagupillay 1996).
However, these estimates were partly based on track counts, a method which assumes
that individual tigers can be uniquely identified from tracks, and that tracks of every
tiger present in an area can be detected (Panwar 1979). In Southeast Asia there are no
long-term sites where workers are able to distinguish individual tigers by the shape of
their tracks. Also in tropical rainforests sign is not always 100% detectable due to
year-round rainfall so these assumptions are violated, and results of such surveys
unreliable (Karanth 1987, 1995, 2003).
In this study, as an alternative, photographs that identified tigers with 100%
confidence were used along with a mark-recapture approach that takes into account
the probability of detecting individual tigers. The results were combined to obtain
sample estimates of tiger numbers for each site. In Peninsular Malaysia, tiger density
varies across forested landscapes (Table 6). However, this variance can be estimated
by sub-sampling density at multiple sites. If the variance is assumed for blocks of
habitat, density can be extrapolated to estimate numbers in those blocks with some
level of confidence. Estimates of tiger numbers are given for individual reserves and
for the 16 TCUs described by Dinerstein et al. (1997)(Table 8). For the purpose of
28
the analysis, for TCUs that were not surveyed (i.e. those in the southern Peninsula
region), tiger density was assumed from adjacent sites or sites with similar
characteristics that were surveyed (see Table 6). We acknowledge that such
extrapolation may not yield precise population estimates, but consider this the best
alternative available at this time for estimating overall population numbers.
In estimating the proportion of habitat occupied by tigers, roads, forest edges, gaps
between forest patches, powerlines, human settlements and other infrastructure were
taken into account since they all pose barriers to dispersal and reproduction (Goosem
1997; Rabinowitz 1993; Woodroffe & Ginsberg 1998). In the absence of more
detailed information, it was assumed that tigers might use only 50% of available
habitat, so that populations might be 50% lower than maximum estimates. For
example, Kawanishi (2002) estimated a maximum range for tigers in Taman Negara
but actual numbers in the park may be less. Thus we arrived at a set of conservative
estimates of tiger populations.
The number of tigers estimated to be in individual reserves in this study ranged from
1-18 tigers. To estimate tiger numbers in TCUs, estimates of tiger density from sites
contained in the TCUs, or from sites near the TCUs were used to extrapolate tiger
numbers (Table 8). For Selama (TCU#130) the density for Bintang Hijau was used.
For the 13 Level III TCUs in the southern Peninsula region, and Endau (TCU#139),
the density for Lepar was assumed. Tigers were confirmed or possibly present in and
near these 14 southern TCU’s since 1987 (Rabinowitz 1999; DWNP unpublished
data), and for the purposes of this analysis tigers were assumed to be still present in
the TCUs. Tiger estimates for TCUs ranged from 3 in Endau to 278 in the Halabala-
Belum-Taman Negara complex (TCU#129). A conservative estimate of the national
tiger population was generated by adding the estimates for all TCUs, assuming 82%
of the estimate for TCU#129 (18% of which lies in Thailand). This resulted in an
estimate of the total tiger population of Peninsular Malaysia of 235 (range=184-305).
29
Table 8. Estimated numbers of tigers in reserves and TCUs in Peninsular Malaysia.
7. Taman Negara d 1.66 1.45-1.87 Reserve 4,343 68(52-84) 34(26-42)
8.Halabala-Belum-
T. Negara
2.02 1.66-2.39 129 a 27,469 555
(456-656)
278
(228-328)
* Area for these sites not defined; a Level I TCU, b Level II TCU, c Level III TCU; d Original data from Kawanishi 2002. Estimate in far right column is interpreted. e Minimum sampling area (222km2) was larger than the size of the reserve so used the latter to calculate density; f Assumes 82% of area of TCU#129 lies inside Peninsular Malaysia
Threats to tigers
Habitat loss and fragmentation are related threats that have direct and indirect
influences on tigers in Peninsular Malaysia. They occur with the creation of road and
power networks, conversion of forests for rubber, coconut and oil plantation,
expansion of urban areas, dams, irrigation, and other planned or unplanned landscape
development (Wikramanayake et al. 2002). Tigers are affected because they are
wide-ranging species that need relatively large (>3,000km 2) areas to sustain long-
term viable populations (Karanth and Nichols 2002). Tigers go rapidly extinct in
small habitat fragments due to conflict with humans at forest edges (Woodroffe and
Site ˆ D
ˆ D min - ˆ D max
Reserve
/ TCU#
Area
(km2)
Raw no.
tigers
(min-max)
50% use
(min-
max)
1. Temenggor 2.68 1.44-3.92 Reserve 1,336 36(19-52) 18(10-26)
2. Ulu Temiang 1.95 1.92-1.98 Reserve 154 e 3(3-3) 2
3. Gunong Tebu 0.60 0.45-0.75 Reserve 255 2(1-2) 1
4. Bintang Hijau 0.74 0-3.63 Reserve 1,167 9(0-42) 5(0-21)
5. Ayer Ngah 0.60 0.45-0.75 Reserve *
6. Lepar 0.58 0.43-0.72 Reserve *
9.Belum-T. Negara 1.90 1.53-2.28 129 a 22,524 f 428
(345-514)
214
(173-257)
10. Selama 0.74 0-3.63 130 b 1,684 12 (0-61) 6(0-30)
11. Endau 0.58 0.43-0.72 139 b 788 5(3-6) 3(2-3)
12. S. Peninsular
Level III TCUs
0.58 0.43-0.72 131-
144 c
4,163 24(18-30) 12(9-15)
P. Malaysia
(sum of 9-12)
235
(184-305)
30
Ginsberg 1998). In Peninsular Malaysia 80% of lowland forests have been lost, with
almost all protected areas less than 500km2 in size, many less than 10km2
(Wikramanayake et al. 2002). Tigers and their largest prey species are mostly absent
from forest fragments smaller than 100km2 (Laidlaw 2000). Tigers also have some
ecological requirements which render them vulnerable to certain types of habitat loss.
Specifically, they depend on access to rivers, so disturbance of or along rivers (e.g. by
roads, dams) can wipe out tigers from areas of otherwise suitable habitat. Logging
alters forest structure and succession, and degrades tiger habitat.
Habitat fragmentation increases accessibility to the remaining forested areas, which in
turn become degraded through a range of human activities. The increased access due
to logging allows for increased hunting (Robinson et al. 1999). Hunting in turn
affects tigers by removing their prey base which can lead to population declines
(Madhusudan and Karanth 2002; Ramakrishnan et al. 1999). Access paths created for
other purposes also facilitate increased hunting. At Temenggor, for example, well-
used trails are traversed by aloewood collectors who hunt illegally to subsist in the
forest. Some of these people were Thai and Lao, as evidenced by carvings in trees in
these languages. Information from former poachers suggests these people spend
several weeks to a month collecting aloewood (P. Klinklay pers. comm.) which is
prevalent in primary and secondary lowland and hill dipterocarp forests in Malaysia
(Barden et al. 2000). Evidence of hunting was found at several sites in this study
(Wan Shahruddin 1998). In general, while there exist a few examples where
populations of tropical wildlife species can be sustained when hunted, there exist
many more examples where hunting is unsustainable and leads to depletion or loss
(e.g case studies in (Robinson & Bennett 1999). The sustainability of hunting has not
been studied in Peninsular Malaysia, but the level of hunting of most species in
tropical forests is known to be low if it is to be sustainable (Robinson 2000).
The increasing frequency of reports of depredation and human injury from tigers in
Peninsular Malaysia (Elagupillay et al. 2001) can either be seen to reflect an increase
in tiger numbers or is evidence that the processes of forest loss and fragmentation, and
over-hunting of prey, are affecting tiger populations. Because our overall estimates
suggest a sharp decline in tiger numbers, we believe the most parsimonious
explanation is that increased conflict reflects increased habitat fragmentation and
31
forest loss. For example, between 1988 and 1997, there were 108 cases of reported
tiger incidents with humans in four out of six states, and 503 reported tiger-livestock
incidents in six states (Elagupillay et al. 2001). Tigers increasingly come into contact
with people as their habitats are encroached upon (Woodroffe & Ginsberg 1998), and
hunting inside forest reserves may deplete prey populations forcing tigers to take
livestock. The effect of tiger mortality through conflict with humans has not been
estimated for tiger populations in Peninsular Malaysia.
Commercial trade in wild tigers and tiger parts has occurred in Asia and across the
world for a very long time (Nowell 2000). Official records indicate it continues today
in Malaysia (Elagupillay et al. 2001), as it does in other countries (Bennett & Rao
2002). The trade is difficult to monitor because it is illegal and involves large
amounts of money, so traders use clandestine methods to disguise it. However,
monitoring is needed to assess impacts on wild populations, and enforcement
measures need to be stepped up to suppress the trade.
Aside from hunting, tiger reproduction and other behaviour may be disrupted and
prey populations displaced by harassment from humans. Eight of nine survey areas
showed evidence of human intrusions in this study (Table 7). Human traffic occurred
in up to a third of the study areas, and was locally intense in some places especially at
Ayer Ngah, Cameron Highlands and Jengai. Malaysian tigers apparently avoid
humans by altering their activity patterns (Fig. 6), as is evidenced in other parts of
their range (Griffiths and van Schaik 1993b).
Habitat loss combined with forest fragmentation due to landscape development
potentially could result in genetic erosion of large mammal populations, such as
tigers, if development creates barriers to dispersal of individuals between forest
patches.
Finally, perceptions that typify tigers as pests are a threat to their survival.
Education programs will be needed to change awareness of officials and the general
public to tigers.
32
Suggested priorities for tiger conservation
In order to plan for the tiger’s future in Peninsular Malaysia, each of the threats
described above need to be considered. Additionally, a set of targets need to be
identified that allow realistic progress to be made in reducing these threats at
appropriate scales of time and space (Ginsberg 2001). Tiger conservation in
Peninsular Malaysia could target the following;
• TCUs that encompass several landscapes;
• Landscapes that contain several populations of females and habitat
connections between the populations;
• Sites that contain at least several breeding females.
Priority Tiger Conservation Units - The Halabala-Belum-Taman Negara Level I
TCU (#129) (Dinerstein et al. 1997) is clearly of highest priority A secondary priority
would be Level I TCU#130 which is small enough (10,000km2) and
connectivity with important tiger habitats in southern Thailand. A second priority is
the Greater Taman Negara Landscape given it’s size (>10,000km2) and the status
of the core part of the landscape as a National Park. Both landscapes contain low-
density tiger populations with supporting prey base in several places.
Priority sites might include;
1. Main Range
a. Belum State Park-Temenggor Forest Reserve complex. The
original Temenggor site surveyed in this study has now been logged
(Abdul Kadir 1998; Wan Shahruddin 1998) but the area may still
support tigers. Currently the east-west Grik Highway divides the area
into two. If connectivity could be re-established by retrofitting the
road with multiple culverts to permit north-south tiger dispersal, and if
systematic wildlife enforcement patrolling can be done, this site would
33
become even more important.
b. Bintang Hijau might be a secondary target given the apparent low
level of human use of the forest.
2. Taman Negara Landscape
a. Taman Negara National Park. Merapoh in the western part of the
park supported the highest density of tigers and lowest human traffic of
three sites surveyed (Kawanishi 2002; p.67), and clearly is a priority
core area within the site. Tigers are threatened by aloewood collectors
who poach prey animals in the park (Barden et al. 2000; Wan
Shahruddin 1998)
3. Krau Wildlife Reserve. A secondary priority site given the problem of
habitat connectivity with the Taman Negara Landscape, and a dwindling tiger
population (DWNP/DANCED 2002). The area is small (531km2) but together
with adjacent forest tracts contains potential tiger habitat. Tiger populations
inside Krau and in adjacent areas could be restored with appropriate
management of prey populations, especially controlling hunting, and habitat
management.
A possible framework which identifies these areas and suggests appropriate short
term and long-term goals for tiger conservation is shown in Table 9. This could form
the basis of future discussions on tiger conservation priorities in Peninsular Malaysia.
34
Table 9. Targets for tiger conservation with various time and spatial scales (adapted
from Ginsberg, 2001).
TARGETS
SHORT TERM (2 – 5 YEARS)
LONG TERM (10 – 20 YEARS)
SITE (An area containing several breeding females) e.g. Belum State Park-Temenggor Forest Reserve complex, Taman Negara NP, Bintang Hijau
• Maintain occupancy of tiger habitat
• Define critical areas within sites
• Stabilize present tiger populations
• Prevent loss of tigers
• Maintain potentially breeding populations of tigers at maximum density
• Maintain expanding population (at r>1)
• Strictly protect core areas
LANDSCAPE (A larger area containing several populations of breeding females) e.g. Main Range, Greater Taman Negara Landscape
• Maintain potential for dispersal between sites
• Maintain ecologically functioning viable tiger populations
• No human intervention required to achieve stable/growing populations
• Recolonization of empty habitat
TIGER CONSERVATION UNIT (An area containing several landscapes) e.g. Halabala-Belum-Taman Negara TCU#129, Selam TCU#130
• Maintain integrity of intact habitat
• Maintain sufficient prey base
• Maintain multiple landscapes including transboundary landscapes in each TCU
• Coordinate establishing protected areas across boundaries
• Promote tiger friendly conservation in each country in TCU
• Re-establish connections between sites and landscapes to ensure genetic exchange
• Maintain heterogeneity of ecoregion
35
36
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