Biological Conservation 89 (1999) 113±120
Tiger decline caused by the reduction of large ungulate prey:
evidence from a study of leopard diets in southern India
Uma Ramakrishnan, Richard G. Coss *, Neil W. Pelkey
Psychology Department and Graduate Group in Ecology, University of California, Davis, CA 95616, USA
Received 13 August 1998; received in revised form 24 November 1998; accepted 4 December 1998
Abstract
Populations of leopards and tigers in the Kalakad-Mundanthurai Tiger Reserve, India, appear to be declining. To identify the
cause of this decline, we examined the diets and the relative densities of leopards and tigers, comparing scat from this park with that
from the Mudumalai Wildlife Sanctuary, a park known to have high leopard and tiger densities. Results suggested that the leopard
density in Mudumalai was approximately twice that in Mundanthurai. No evidence of tigers was found in Mundanthurai. Prey
species found in leopard diets in the two parks was similar; albeit, mean prey weight and the proportion of large ungulates were
markedly lower in the Mundanthurai leopard diet. These dietary di€erences are consistent with the infrequent sightings of large
ungulates in Mundanthurai. Analyses of satellite data revealed that large areas of grazing land in Mundanthurai have shifted to
thicket, reducing available forage for large ungulates. Since large ungulates constitute important tiger prey, the low density of
ungulates in Mundanthurai might explain the apparent absence of tigers. Our ®ndings suggest that the tiger population in the
Kalakad-Mundanthurai Tiger Reserve could be enhanced via the application of habitat management for large ungulates. # 1999
Elsevier Science Ltd. All rights reserved.
Keywords: Conservation; Habitat management; Scat analysis; Leopard; Tiger
1. Introduction
The tiger (Panthera tigris) has been classi®ed as
endangered by the IUCN, with about 6000±8000 surviving in the wild (Nowak, 1991). The major threat to
its survival is habitat loss and the poaching of tigers and
their prey (Nowell and Jackson, 1996). India supports
the largest numbers of tigers in the wild, approximately
two thirds of the world's tiger population (Sunquist and
Shah, 1997). The most recent survey estimated the
number of tigers throughout India at 3750 (Ghosh,
1994). Their distribution in southern India is shown in
Fig. 1A. Tiger densities in the wild increased moderately
in the 1980s because of intensive e€orts to protect the
species with the establishment of reserves targeted for
tigers in India (Karanth, 1987; Panwar, 1987). This
e€ort led to the rapid increase in prey populations with
a corresponding increase in tiger populations (Sunquist,
1996). More speci®cally, tiger densities increased with
the availability of large ungulate prey in the region
* Corresponding author. Tel.: +1-530-7521626; fax: +1-5307522087; e-mail: [email protected].
(Karanth, 1987; Sunquist and Sunquist, 1989). Though
facing the same threats, leopards (Panthera pardus) are
more successful than tigers, largely because of their
ability to live in di€erent environments and the ¯exiblity
in their diet (Bailey, 1993). The wide geographic distribution of leopards is also attributed to their ability to
coexist with other large carnivores (Bailey, 1993). Both
tigers and leopards are solitary, stealth predators. Tigers
are usually restricted to the core areas of protected
reserves and avoid areas of moderate to heavy human
disturbance. They are dependent on dense vegetative
cover and access to water (Nowell and Jackson, 1996).
1.1. Recent habitat changes in the KalakadMundanthurai Tiger Reserve
The Mundanthurai sanctuary was classi®ed as a tiger
reserve in 1988 because of the occurrence of tiger sightings and other tiger evidence. However, in the last 2
years, there have been very few sightings of tigers (Forest Department records). Some major changes in habitat
management have occurred in Mundanthurai over the
last decade; the frequency and intensity of forest ®res
were controlled and cattle were excluded from most
0006-3207/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved.
PII: S0006-3207(98)00159-1
114
U. Ramakrishnan et al. / Biological Conservation 89 (1999) 113±120
Fig. 1. Distribution of tigers in southern India (A). Study sites for the collection of tiger and leopard scat on the Mundanthurai Plateau (B) within
the Kalakad-Mundanthurai Tiger Reserve and within the Mudumalai Wildlife Sanctuary (C).
areas of the park. These factors led to the decline of
grasslands available for herbivores. The reduction in
forest ®res led to an increase in unpalatable exotic
thickets, such as lantana (Lantana camara) and eupatorium (Eupatorium glandulosum). Although important
for forest management, the sudden removal of cattle
from areas in the park coupled with ®re control augmented the growth of these exotic weeds. At present,
no systematic research has examined the e€ects of
declining grazing lands on herbivore populations in this
park.
A number of studies have been conducted on large
carnivore species in southern India (Johnsingh, 1983;
Karanth and Sunquist, 1995; Rice, 1986; Venkataraman
et al., 1995). These studies were designed to obtain
information on predator distribution and diet in a given
park or reserve. The current study focused on comparing
the diet of leopards and tigers in the Kalakad-Mundanthurai Tiger Reserve with a region known for its
healthy carnivore population, the Mudumalai Wildlife
Sanctuary. When the key item of a carnivores' diet is in
short supply, the carnivore species will either alter its
diet or exhibit a drop in population size. A comparison
of carnivore densities and diets in these two wildlife
parks will shed light on which of these two e€ects have
occurred. Previous studies on the diets of sympatric
leopards and tigers have shown that their diets are very
similar when prey are abundant (Schaller, 1967; Johnsingh, 1983; Karanth and Sunquist, 1995). However,
leopards tend to be more ¯exible in their diets than
tigers under deteriorating habitat conditions (Johnsingh, 1983). It is reasonable to predict that a shift in the
diet of leopards toward smaller prey is an indication of
the low availability of larger prey favored by tigers.
U. Ramakrishnan et al. / Biological Conservation 89 (1999) 113±120
2. Study sites and methods
Data collection was conducted from March to
September, 1997 at two study sites. The KalakadMundanthurai Tiger Reserve is located between 8 250 ±
8 530 N latitude and 77 100 ±77 350 E longitude, and
covers an area of 817 km2 (Fig. 1B). The habitat type
consists of moist evergreen rain forest, moist and dry
deciduous forest, and scrub forest. Our sampling was
restricted to the Mundanthurai Plateau and occurred
over multiple paths, totaling a 48.3-km distance. The
habitat type of the plateau is classi®ed as mixed deciduous (Ali, 1981).
The Mudumalai Wildlife Sanctuary is located
between 11 320 ±11 430 N latitude and 76 220 ±76 450 E
longitude and covers an area of 321 km2 (Fig. 1C). This
park has a variety of vegetation types, consisting of
tropical semi-evergreen forest, moist and dry deciduous
forest, and dry thorn forest (Sukumar et al., 1992). Our
sampling was restricted to moist and dry deciduous
forest areas and occurred over multiple paths, totaling a
46.7-km distance.
These two forest sites are part of a complex classi®ed
as ``high-priority'' tiger conservation sites, which a€ord
the highest probability of long-term persistence of tiger
populations (Wikramanayake et al., 1998). Both study
sites have very similar mammalian species. The large
carnivores include the leopard, tiger, wild dog (Cuon
alpinus), and striped hyena (Hyaena hyaena). Prey species also appears to be similar in the two parks (Forest
Department records).
The hair of prey is relatively undamaged in carnivore
scat and can thus be used to identify the prey species
eaten. We collected leopard and tiger scat from multiple
established forest paths. Each path was sampled once a
month for 5 months. This period covered two seasons, a
dry and a wet season. Since leopards and tigers are more
likely to defecate on forest paths or on grassy areas just
bordering the paths (Sunquist, 1981; Johnsingh, 1983;
Norton et al., 1986; Karanth and Sunquist, 1995), only
forest paths were searched. Excess scat was removed
from the paths to prevent repeated sampling at the next
sampling period. The samples were sealed in plastic
bags and labeled for path location and date. Tiger scat
was distinguished from leopard scat by pug marks and
size of scat. A full-grown leopard is about one fourth
the size of a full-grown tiger (Seidensticker, 1976), thus
producing identi®ably smaller scat. Although it is possible that scat from a tiger cub less than six months of
age could be misclassi®ed as leopard scat, it would constitute a very small fraction of our sample. The scat
samples were washed in water using a 1.5 mm sieve to
separate the hair from other organic matter. Separated
hair was then washed in hot water to remove surface oil.
Each scat sample was washed separately in acetone and
dehydrated in 100% ethanol.
115
To create permanent slides for species identi®cation,
®ve hairs were selected randomly from each sample,
centered parallel on the slide, and mounted with cover
slip using DPX mount. Five slides were made per scat
sample (n ˆ 25 hairs/sample). Slides were examined at
400X using an Olympus microscope. For identi®cation
of scat hairs, a set of reference slides was made from
captive prey species, museum specimens, and leopard
kills. For statistical quanti®cation, each species found in
one scat sample was assumed to characterize a single
predatory event. Di€erence of proportions tests were
conducted to compare diets between parks using NCSS
statistical software (Hintze, 1987).
Apart from scat collection, the presence of tigers and
leopards during the entire study was recorded by direct
sightings, both by researchers and local residents, and
the presence of tiger and leopard pug marks and
scrapes. Sightings by local residents living in Mundanthurai were recorded through an oral interview
using a formal questionnaire to quantify evidence of
predation on domesticated animals. The settlements
selected for study were ®ve separate tribal colonies, two
at the edge of the park and three in the forest interior.
One adult per household was interviewed (n ˆ 58).
Although we did not attempt to estimate prey densities in the two parks, we recorded all sightings of chital
deer while collecting scat throughout the parks. Because
the density of herbivore prey is a€ected by habitat preferences (Eisenberg and Seidensticker, 1976), we also
estimated changes in grass cover available for grazing in
the two parks. Satellite data with a 1-km2 resolution
from the NOAA Advanced Very High Resolution
Radiometer was used to measure changes in grazing land
between 1986 and 1996. This data set was produced by
the National Institute for Environmental Studies of the
Environment Agency of Japan. It consisted of cloudfree digital maps for the dry season (January±March) of
each year. The lea¯ess deciduous trees during the dry
season permitted the detection of ground cover otherwise occluded by forest canopy. Each digital map used
for quanti®cation was developed by mosaicking several
radiometer scenes in order to obtain a cloud-free image
(see Pelkey, 1997). The vegetation index was computed
from the ®nal image, which characterized the widerange distribution of vegetative conditions. We calculated grazing land by coding areas with the Calibrated
Vegetation Index (Kidwell, 1991), using 100±120 as the
index for the grass category and >120 as the index for
thicket or forest (Goetz, 1997; Pelkey, 1997). We compared only the 1986 and 1996 dry season data.
3. Results
The leopard and tiger evidence collected in the two
parks during this study are summarized in Table 1.
116
U. Ramakrishnan et al. / Biological Conservation 89 (1999) 113±120
Table 1
Evidence of leopards and tigers collected in the Mudumalai Wildlife
Sanctuary and on the Mundanthurai Plateau
Tiger sightings
Tiger scat
Tiger pug marks
Leopard sightings
Leopard scat
Leopard pug marks
Mudumalai
Mundanthurai
3
9
6
2
185
16
0
0
0
2
111
9
There was no evidence of tigers in the Kalakad-Mundanthurai Tiger Reserve during the study period, either
observed directly or reported during the interviews. In
Mudumalai, 9 tiger scats were collected, 6 of which
contained evidence of chital deer (Axis axis) and 3 of
sambar deer (Cervus unicolor). Leopards, though not as
common in Mundanthurai as in Mudumalai, were
sighted twice in each park; 111 scat samples were collected in Mundanthurai compared with 185 scat samples collected in Mudumalai.
The proportion of prey species in the diet of leopards
in the two regions appears in Fig. 2. The chital deer is
the primary prey species in both regions, contributing
over 50% of the leopard's diet in Mudumalai. The
number of di€erent species that leopards fed upon did
not di€er appreciably between the two regions. Di€erence of proportions tests, comparing the contribution of
each prey type to the diet of leopards in the two regions,
revealed that 6 species were signi®cantly di€erent in the
two regions (Table 2). Of the 6 species that di€ered signi®cantly using two-tailed tests ( ˆ 0:05), 5 were small
species. The black-napped hare (Lepus nigricollis), rat
(Rattus rattus), pangolin (Manis crassicaudata), munjac
deer (Muntiacus muntjak), and porcupine (Hystrix
indica) were markedly more abundant in the Mundanthurai leopard diet (p < 0:025). The sixth species
that di€ered was the chital deer, which contributed to
67.2% of the leopard diet in Mudumalai, but only
24.3% in Mundanthurai (p < 0:0001). Because the
emphasis herein is the comparison of the contribution
of the same prey species in the leopard diet between
parks, the relationship of prey body size to overall diet
contribution will not be addressed. This is in contrast
with Norton et al. (1986) who examined the dietary
contribution of prey within a single park.
To generalize our ®ndings of park di€erences to other
parks in southern India, we compared our data with
recent data from Nagarhole National Park, n ˆ 459 scat
samples (Karanth and Sunquist, 1995) and Bandipur
National Park, n ˆ 76 scat samples (Johnsingh, 1983).
Leopard prey species were categorized into the following three body weight classes: (1) 0±20 kgÐblack napped hare, rat, pangolin, bonnet macaque (Macaca
radiata), porcupine, domestic dog (Canis familiaris),
Fig. 2. Proportional contribution of prey to the leopard diet at the
two study sites.
munjac deer, Nilgiri langur (Trachypithecus johnii) and
Hanuman langur (Semnopithecus entellus); (2) 21±50
kgÐchital deer, wild boar (Sus Scrofa); (3) >50 kgÐ
domestic cattle (Bos taurus), sambar deer, Indian bison/
gaur (Bos gaurus). The contribution of each of these
weight classes to the leopard diet from four parks in the
region is shown in Fig. 3. The proportion of heavy prey
(>50 kg) did not di€er appreciably in the four parks.
However, a di€erence of proportions test illustrates the
highest proportion of small prey (0±20 kg) selected by
leopards in Mundanthurai compared with each of the
other three parks (p < 0:01). In contrast, the mediumsized prey class (21±50 kg) was signi®cantly lower in
Mundanthurai than the other three parks (p < 0:01).
U. Ramakrishnan et al. / Biological Conservation 89 (1999) 113±120
Table 2
Di€erence of proportions tests, comparing the proportion of prey hair
found in leopard scat in the Mudumalai Wildlife Sanctuary and on the
Mundanthurai Plateau
Species
Mudumalai Mundanthurai Z-valuesa p<
(% of total) (% of total)
Black napped hare
Chital deer
Domestic dog
Wild boar
Domestic cattle
Sambar deer
Rat
Indian bison
Munjac deer
Pangolin
Nilgiri langur
Bonnet macaque
Hanuman langur
Porcupine
Unclassi®ed
Total samples
3.35
67.22
2.79
1.11
6.14
11.66
1.67
0.56
2.23
0
0
0
2.79
0.56
3.35
100
13.89
24.32
6.48
3.70
8.33
9
7.41
0
8.33
4.63
8.33
0.92
0.92
5.55
3.70
100
ÿ3.3208
7.1102
ÿ1.5123
ÿ1.4837
ÿ0.7053
0.7138
ÿ2.4501
0.7781
ÿ2.4070
ÿ2.9041
*
ÿ1.2897
*
ÿ2.6586
ÿ0.1574
0.0001
0.0001
0.130
0.138
0.480
0.762
0.014
0.436
0.016
0.003
0.1971
0.007
0.875
a
Note that negative Z-values indicate that the proportion of the
speci®c species was higher in Mundanthurai.
*
Nilgiri langurs and Hanuman langurs were not compared because
scat collection was conducted in areas where the two species were
mutually exclusive.
Felids are extremely dicult to census (Karanth,
1987; Nowell and Jackson, 1996), hence we attempted
to compare the relative density of leopards in the two
parks using an index of leopard scat density. To achieve
this, we compared the number of scats collected with the
linear distance covered in one month, which included all
trails sampled only once. Therefore,
Relative density ˆ Number of scats=total trail distance
117
A total of 48.3 km distance was surveyed per month
in Mundanthurai and 46.7 km distance in Mudumalai.
The density of leopard scats in Mundanthurai was 0.87
scats/km and 1.31 scats/km in Mudumalai. Thus,
assuming that scat density is correlated with leopard
density, the density of leopards in Mudumalai appears
to be almost twice as high as in Mundanthurai.
Recorded sightings of chital herds from the randomly
distributed trails permitted the comparison of the difference in the frequency of encounters in the two parks.
In the 145-km distance covered in Mundanthurai during
the total sampling period, chital herds were encountered
4 times; in the 140-km distance covered in Mudumalai,
chital herds were encountered 17 times. These frequencies
di€ered signi®cantly (p < 0:01, two-tailed binomial test).
The distribution of scat also indicates that leopards in
Mundanthurai were preferentially distributed near
human settlementsÐthere was a higher density of leopard scat within a 5-km radius of human settlements
(1.26 scats/km compared with 0.69 scats/km beyond 5
km). One of the key indices of the leopards' preferential
use of areas near human habitation was revealed in the
survey of local human residents. A total of 58 families
were surveyed to quantify predation on domestic animals. Thirty-four families surveyed had lost chickens to
leopards at least once. Thirty-one families had lost cattle to leopards. Twenty-three families admitted to stealing kills from leopards, if the kill was a sambar deer,
chital deer or wild boar. Such prey-stealing by humans
has been reported for other areas (Johnsingh, 1983).
Comparisons of grazing land changes in the two
parks from the 1-km2 resolution satellite data using the
Calibrated Vegetation Index revealed that, in Mundanthurai, 42.6% of grazing land in a 101 km2 area
measured from 1986 data had shifted to thicket by 1996.
In contrast, 199 km2 area of grazing land measured in
Mudumalai in 1986 remained essentially unchanged in
1996.
4. Discussion
Fig. 3. The occurrence of prey in leopard diet as a function of weight
class is shown for four parks in southern India. Note that prey
exceeding 50 kg did not di€er signi®cantly among the parks whereas
prey between 21 and 50 kg were signi®cantly lower in Mundanthurai
than in the other parks (p < 0:01). Conversely, prey less 21 kg were
signi®cantly more abundant in Mundanthurai (p < 0:01).
The lack of tiger scat in Mundanthurai suggests that
the park, classi®ed as a tiger reserve because of its once
high tiger densities, has very few, if any, tigers left. It is
possible to misclassify the scat of young tiger cubs (less
than 6 months of age) as leopard scat; albeit, there
should be an overlapping distribution of tiger cub scat
and adult tiger scat because tiger cubs continue to live
with their mothers until 2±3 years of age (Nowak, 1991).
Since we did not ®nd any adult tiger scat in Mundanthurai, it is unlikely that we misclassi®ed tiger cub
scat as leopard scat.
The ®ndings of this study suggest that leopards in
Mundanthurai are feeding on smaller and perhaps less
preferred prey, probably as a result of low ungulate
118
U. Ramakrishnan et al. / Biological Conservation 89 (1999) 113±120
density. However, a low density of large prey may not
adversely a€ect the leopard population. Leopards are
opportunists and are very ¯exible in their diet, and can
thus survive in a region where the ungulate densities are
low. Their ability to feed on both small and large prey,
to climb trees and scavenge (Johnsingh, 1983) may help
them survive in a highly disturbed habitat where prey
are scarce. Tigers, on the other hand, are not good
climbers, limiting their ability to hunt arboreal prey,
none of which were found in the Mudumalai tiger scats.
Unlike tigers, leopards are more likely to move through
open terrain and raid villages for domestic animals,
which allows them to survive in fragmented habitats
(Seidensticker and Lumpkin, 1996). Although meagre,
our sample of tiger scat from Mudumalai suggests that
tigers are focusing on large ungulate prey. The much
heavier tiger, about four times the weight of leopards
(Seidensticker, 1976), probably cannot survive on very
small prey. In light of our ®ndings, it seems reasonable
to suggest that increasing large ungulate densities in
Mundanthurai would probably attract tigers to the
park.
Based on other studies in southern India, there is a
large overlap in leopard, wild dog, and tiger diet preferences (Johnsingh, 1983; Karanth and Sunquist,
1995). Evidence suggests that among large sympatric
carnivores, the larger carnivores can prey on broader
size ranges of prey classes due to their prey handling
capabilities (Gittleman, 1983). In Chitawan National
Park where tigers and leopards coexist, tigers were
recorded taking a much wider range of prey sizes than
leopards (Seidensticker, 1976). In regions of high tiger
density, for example, tigers are known to out-compete
leopards (McDougal, 1988; Schaller, 1967,1972), the
capacity of which includes opportunistic stealing of
leopard prey as well as killing leopards (Seidensticker,
1976). Radio-tracking studies on tiger and leopard
movements indicate that leopards avoid areas frequented by tigers (Seidensticker, 1976), preferring the
periphery of parks near human settlements. However, in
regions of low tiger density, such interspeci®c social
dominance is not common (Robinowitz, 1989); leopards
are known to have a more diverse prey base than tigers
in the lower weight classes of prey. Results from the
current study and that of other studies in the region
appear to support these ®ndings (Johnsingh, 1983;
Karanth and Sunquist, 1995; Rice, 1986). Thus, a low
density of prey in the higher weight classes can restrict
the distribution of tigers, but may not a€ect leopard
distribution.
The results of our study of leopard diet in the Mudumalai Wildlife Sanctuary is consistent with those from
the adjacent Bandipur Tiger Reserve (Fig. 1A,C) and
Nagarhole National Park (Johnsingh, 1983; Karanth
and Sunquist, 1995). It is also consistent with the ®ndings from Chitawan National Park (Seidensticker, 1976)
in northern India. In Bandipur and Nagarhole, the
complexity of the vegetation types and the large prey
base were reported to be the main reasons for the coexistence of leopards and tigers in these areas. Similarly, in
Chitawan National Park, the coexistence of tigers and
leopards has been credited to the abundance of prey in
both the larger and smaller weight classes.
Previous studies have looked at the prey preference of
large carnivores as a function of prey size (Karanth and
Sunquist, 1995; Scheel, 1993). These studies compared
their observations in light of foraging theory (Stephens
and Krebs, 1987), where the most pro®table prey is that
measured by the ratio of energy gain to prey-handling
time. Leopard prey typically range in weight from a few
100 g (e.g. rodents) to over 100 kg, with the preferred
weight being between 20 and 50 kg. Similar observations
have been made in Africa (Schaller, 1972) where leopards preferentially kill prey in the 20±70 kg weight
class. Thus, chital deer would appear to be the most
pro®table preyÐlarge enough to provide a full meal and
small enough to not cause major harm to the predator.
Although wild boar fall under the same weight-class
category as chital deer, they are very aggressive and can
retaliate viciously, which can cause serious injury to an
attacking leopard. Similarly, sambar deer are larger and
more aggressive than chital deer, and this could be a
reason for their lower occurrence in our scat samples.
Complementary ®ndings of tiger diet support this argument because chital deer are the most frequently eaten
prey (Nagarhole park, Karanth and Sunquist, 1995;
Chitawan park, McDougal, 1977; Kanha park, Schaller,
1967).
Chital deer have a wide geographic distribution and
are found throughout the Indian sub-continent. Density
estimates of chital deer have been recorded for three of
the four parks mentioned above. Varman and Sukumar
(1995) estimated a density of 25 chital/km2 in Mudumalai. Karanth and Sunquist (1995) estimated a density
of 49 chital/km2 in Nagarhole. A similar survey of prey
densities conducted in Bandipur revealed an estimated
density of 44 chital/km2 (Johnsingh, 1983). Although no
prey density estimation studies have been conducted in
Mundanthurai, our infrequent observations of chital
herds suggest that their density is much lower than in
Mudumalai.
The rapid decline in tiger populations world wide has
been attributed to habitat loss and poaching (Nowell
and Jackson, 1996). Our failure to observe tiger pug
marks and tiger scat during this study seems to indicate
that there are very few tigers on the Mundanthurai Plateau. Most of the conservation initiatives for the tiger
have focused on setting aside reserves to protect important tiger habitat (Cox, 1998) and that was one of the
major objectives of the Kalakad-Mundanthurai Tiger
Reserve. However, it appears that protection of the
habitat alone is not sucient; some modi®cations to the
U. Ramakrishnan et al. / Biological Conservation 89 (1999) 113±120
habitat might be essential to restore tigers in this park.
Park management decisions for increasing large carnivores in the park can be based on prey density estimates
coupled with the study of leopard diets. Since this is the
®rst study on carnivore diets in Mundanthurai, we are
unable to record di€erences in diet that resulted from
recent changes in park management. Future research
should focus on con®rming our tentative conclusion
that the large ungulate densities are low in the park and
determining the causes of this decline. Hunting of large
ungulates by humans is minimal in this park and is thus
not a contributing factor. Vegetation changes, such as
the reduction of available grasses for grazing, might
explain this decline in large ungulates. The optimum
habitat for ungulates, especially chital, has been shown
to consist of grasses interspersed with shrubs and trees
(Eisenberg and Seidensticker, 1976). Comparisons of
current vegetation cover, both grasslands and forest
understory, with that of earlier surveys will shed light
on the relationship between habitat change and its
e€ects on large ungulates essential for tiger survival.
Acknowledgements
We thank the Forest Department of Tamil Nadu for
permission to conduct research in the Kalakad-Mundanthurai Tiger Reserve and Mudumalai Wildlife
Sanctuary. We would also like to thank R. Arumugum
for assistance in applying scat analysis techniques and
Anil Kumar, M. Siddhan, and Yashoda for their contribution in data collection. We thank Drs. L. Isbell, C.
Schonewald and two anonymous reviewers for suggestions which improved the manuscript.
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