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C 2006) International Journal of Primatology, Vol. 27, No. 4, August 2006 ( DOI: 10.1007/s10764-006-9054-z

Distribution, Habitat Correlates, and Conservation of Loris lydekkerianus in Karnataka, India H. N. Kumara,1 Mewa Singh,1,2 and Shanthala Kumar1 Received November 3, 2004; revision March 26, 2005; 2nd revision June 21, 2005; accepted July 15, 2005; Published Online September 12, 2006

We surveyed slender lorises (Loris lydekkerianus) in Karnataka, south India intermittently during November 2001–July 2004 and estimated their relative abundance via direct sightings. Two subspecies, Loris lydekkerianus lydekkerianus and L. l. malabaricus, with different morphological traits, occur in the eastern drier region and the western wet region of the state, respectively. The distribution of Loris lydekkerianus lydekkerianus is patchy in a small region in the southeast, which contradicts earlier reports of its abundance throughout the state. Loris lydekkerianus malabaricus occurs throughout the Western Ghats as a contiguous population. The encounter rates of Loris lydekkerianus lydekkerianus and L. l. malabaricus are 0.41 individuals/km and 0.21 individuals/km, respectively. Whereas several forest tracts in the distributional range of Loris lydekkerianus malabaricus are protected areas, no such area exists in the distributional range of L. l. lydekkerianus. Loris lydekkerianus faces serious challenges of conservation because it largely occurs in commercial plantations, which can be relatively unstable habitats as harvesting can take place at any time. KEY WORDS: conservation; Eastern Ghats; Karnataka; Loris lydekkerianus lydekkerianus; Loris lydekkerianus malabaricus; loris distribution; loris morphology; slender loris; Western Ghats.

1 Biopsychology

Laboratory, University of Mysore, Mysore 570006, India.

2 To whom correspondence should be addressed; e-mail: [email protected].

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Kumara, Singh, and Kumar

INTRODUCTION Slender lorises are nocturnal primates living in Sri Lanka and southern India (Roonwal and Mohnot, 1977) and are listed as Data Deficient in the IUCN Red List of Threatened Species (Baillie et al., 2004). Before Groves (2001), primatologists considered slender lorises as only 1 species with 6 subspecies differentiated by pelage, body mass, and geographic locations. Researchers found 4 subspecies of slender lorises occur in Sri Lanka and 2 in India. Groves (2001) regrouped them into 2 species— Loris lydekkerianus in India and Sri Lanka and Loris tardigradus only in Sri Lanka. The 2 subspecies in India include Loris lydekkerianus lydekkerianus in the drier forests of the Eastern Ghats south of river Godavari and Loris lydekkerianus malabaricus in the wet forests of the Western Ghats south of river Tapti (Groves, 2001; Roonwal and Mohnot, 1977). Schulze and Meier (1995) provided the only relatively comprehensive map of the distribution of slender lorises in southern India, based on area estimates of Osman Hill (1933, 1953) and Fiedler (1956), the information on the origin of museum specimens collected between 1889 and 1929 (Jenkins, 1987), sight records, animal collections for laboratory research, and other surveys that mentioned localities (Blanford, 1888; Devaraj Sarkar et al., 1981; Johnson, 1984; Manjula, 1984; Ramaswami and Kumar, 1967; Rao, 1994; Ryley, 1913; Sarma and Kadam, 1984; Seth, 1963; Swayamprabha and Kadam, 1980; Wroughton, 1917). Schulze and Meier (1995) based their projections of the distribution of loris subspecies on sporadic information collected over almost a century, during which numerous changes have taken place in the natural habitat as a result of accelerated urbanization, growing human population, and conversion of natural forests into agricultural land. Along with the loss of habitat (Karanth, 1986), hunting has also affected the distribution and status of slender lorises (Schulze et al., 2005). The field data from systematic surveys have hardly been available on slender lorises, probably because it is small, usually solitary, and nocturnal. Singh et al. (1999) initiated systematic surveys on the distribution of slender lorises and found potential populations in forests of Dindigul District in Tamilnadu. They later extended the surveys to the forests of the Eastern Ghats and adjoining regions in southern Andhra Pradesh (Singh et al., 2000). Lakshmi and Mohan (2002) also provide loris distribution in Andhra Pradesh. Lorises also occur in the eastern forests of the Indira Gandhi Wildlife Sanctuary in Tamilnadu (Kumar et al., 2002). Nekaris (2001, 2003) and Radhakrishna and Singh (2002a,b,c, 2004a,b) conducted long-term studies on the ecology and behavior of slender lorises in the

Loris lydekkerianus in Karnataka, India

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forests of Dindigul, but large areas considered to be the distributional range of slender lorises still remain unexplored. During ongoing studies on the ecology and distribution of mammals in southern India, we found no loris in several regions where they were previously abundant (Devaraj Sarkar et al., 1981; Schulze and Meier, 1995). Because many such areas are protected areas (notified Wildlife Sanctuaries and National Parks), there is little chance that lorises would have disappeared from them recently. There is an urgent need for field studies to assess the status of slender lorises via first-hand instead of secondary or unsubstantiated information. We report here the results of our survey in the south Indian state of Karnataka over 3 yr.

STUDY AREAS We studied slender lorises intermittently from November 2001 to July 2004 in the south Indian state of Karnataka between 11◦ 31 –18◦ 45 N and 74◦ 12 –78◦ 40 E. Karnataka has a total area of 1,91,791 km2 and the mean annual rainfall is 1975 mm, ranging from 450 mm to 7500 mm. On the basis of physical features, climate, and vegetation types, Karnataka is divided into 4 representative ecozones including Coastal Karnataka with mangrove forests; Hill Region (the Western Ghats) with rain forests and moist deciduous forests; and Southern Plateau and Northern Plains with deciduous forests, scrub forests, and open grasslands (Karanth, 1986; Prasad et al., 1978).

Southern Plateau and Northern Plains Because the forests in the southern and the northern plains of Karnataka are not contiguous, we did not select specific locations for intensive surveys. Stray rocks dominate the northern plains and the vegetation is only patchy and degraded. The Eastern Ghats hill ranges with good vegetation, especially of Acacia, pass through the southern plateau. There are some good and intact forest patches in Kolar, Bangalore (Rural), Tumkur, and Chamarajanagar. The forests at the westernmost edge of the Eastern Ghats connect with the forests of the easternmost edge of the Western Ghats in Chamarajanagar. Some of the major protected areas in the region include Cauvery Wildlife Sanctuary, Malai Mahadeshwara Betta (MM Hills), Biligiri Rangaswamy Temple Wildlife Sanctuary (BRT), and Bandipur National Park (Bandipur).

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Coastal Karnataka The few remaining mangrove forests are now only in Uttara Kannada, Udupi, and Dakshina Kannada, mostly in patches of a few hectares at the sea shore. The Western Ghats Because the hill ranges and the forests in the Western Ghats are contiguous from south to north, we carried out intensive surveys in 3 selected areas—Brahmagiri-Makut, Pushpagiri-Bisale, and Sirsi-Honnavara. The 324-km2 forests of Brahmagiri-Makut lie between 75◦ 50 –76◦ 3 E and 12◦ 5 –12◦ 13 N. Elevation is 60 m asl–1750 m asl. The area receives both southwest and northeast monsoons, with an average annual rainfall of ca. 6000 mm. The forests are broadly classified as Medium Altitude Forest Type with Mesua ferrea–Palaquium ellipticum vegetation (Pascal, 1988). The forests of Pushpagiri-Bisale lie between 75◦ 38 –75◦ 42 E and 12◦ 34 –12◦ 52 N with an area of 211 km2 in Kodagu, Hassan, and Dakshina Kannada. Elevation of the region is 150 m asl–1000 m asl and the annual rainfall is ≤ 6000 mm. The vegetation type of the area is classified as Mesua ferrea–Palaquium ellipticum type. The forests of Sirsi-Honnavara lie between 74◦ 35 –74◦ 47 E and 14◦ 15 –14◦ 25 N in the district of Uttara Kannada. The selected study area, with about 200 km2 of rain forest, was between the Sharavathy and Aghanashini rivers. The region receives ≤ 5000 mm of rain at the crest of the Ghats and the altitude ranges from 98 to 700 m asl. The forests of this region are broadly classified as Low Altitude Rain Forest with Persea macrantha-Diospyros spp.–Holigarna spp. vegetation (Pascal, 1988). Further details of the study regions at Brahmagiri-Makut and Sirsi-Honnavara are in Kumara and Singh (2004a,b). We also selected 2 areas adjacent to the Western Ghats on the eastern side: Rajiv Gandhi National Park and Nugu Wildlife Sanctuary (Nugu). Rajiv Gandhi National Park, with an area of 643 km2 , lies between ◦ 76 00 –76◦ 17 E and 11◦ 51 –12◦ 15 N. The annual rainfall is 1000–1500 mm and the altitude is 700 m asl–957 m asl. The southwest of the park has moist deciduous forests (Tectona-Dillenia–Lagerstroemia series) and the northeast part has dry deciduous forests (Terminalia-Anogeissus–Tectona series). Nugu Wildlife Sanctuary is southeast of Rajiv Gandhi National Park, and the forest is continuous with Bandipur National Park. The total area of the Sanctuary is 30.32 km2 , and it lies between 76◦ 26 –76◦ 28 E and 11◦ 52 –11◦ 59 N, with an average annual rainfall of 1000 mm. The major forest of the Sanctuary is dry deciduous scrub with very few tall trees.


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METHODS We first gathered information on occurrence of slender lorises in different taluks3 of Karnataka to prepare the distribution map. Several taluks together form a revenue district. We considered a taluk as the smallest unit area for the distribution of slender lorises. In each taluk, we visited forests and collected information on stand structure of vegetation and assessed the habitat available and suitability of the vegetation for slender lorises. We also reviewed the existing documents in the Forest Department and talked with its personnel, local villagers (especially elders), hunters, and shepherds around the forests regarding the occurrence of slender lorises. If any of the sources revealed the presence of slender lorises in a taluk, we intensively surveyed that taluk to assess the present status of the species. We carried out the intensive surveys in November 2001–January 2002 in Brahmagiri-Makut, February 2002–April 2002 in Sirsi-Honnavara, April 2003 in Nugu Wildlife Sanctuary, May 2003–June 2003 in Pushpagiri-Bisle, August 2003–September 2003 in Mandya and Tumkur, February 2004– March 2004 in Rajiv Gandhi National Park, and May 2004–July 2004 in Bangalore, Mandya, and Kolar. Because local information revealed no slender loris in coastal Karnataka, we did not explore the region. Because the area covered was large, we focused only on relative abundance and distribution patterns rather than on absolute densities of slender lorises. We adopted the methods of Singh et al. (1999, 2000). We conducted the entire survey at night (2000–0300 h), though we collected some information on vegetation during the day. We made no attempt to control for moonlight level when surveying. We carried out the survey in the Western Ghats on foot and in the dry areas of Southern Plateau in a vehicle. We walked on preexisting trails at 0.5 km/h by flashing light (Maglite 3-battery torch) on both sides. We used a pedometer to record the distance covered on foot. During a vehicular survey, a researcher sat atop a jeep moving at 5–10 km/h and flashed a light connected to the jeep battery. The tapetum lucidum in the slender loris eye produces an orangered reflection, which is very different from the eye reflections of other nocturnal species. On sighting a slender loris, we approached the individual and recorded tree height in which we sighted it, height of the individual in the tree, tree species, and altitude. We could not record detailed data on tree species all the time in the Western Ghats. However, we recorded such information in the Plateau region. We selected a 5-m radius plot around the trees in which we sighted slender lorises and recorded data on habitat parameters including type of forest, presence of bushes, contiguity of the 3A

taluk is a revenue administrative unit with a defined boundary and an area of about 1000 km2 .

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forest, presence of climbers/lianas, and number of tall trees with a girth >30 cm. When we found a slender loris in bushes or in lower canopies in the nonprotected areas, we caught it by hand, wearing leather gloves. We also obtained 1 injured individual from a villager. We took several body measurements with standard sliding calipers and a sensitive weighing balance, following a standard procedure (Schulze et al., 2004), and calculated the standard anthropometric indices of Jungers (1985). We made the distribution map by taking a taluk as the smallest unit for presence and absence of slender lorises. The relative abundance is the encounter rate (individuals/km). For a statistical test of difference in encounter rates, we based expectations under the null hypothesis on km of censuses. The dry plains did not have much altitudinal variation, and we ignored it for analysis. In the Plateau and dry plains, the distribution of slender lorises is patchy and restricted to fragmented tracts of forests. To localize conservation efforts, we showed the distribution data for the region at the level of a taluk. However, in the Western Ghats, loris distribution was continuous throughout the hill ranges and we do not show the taluk-level details.

RESULTS Vernacular Names In Karnataka in general, and in all drier districts, a slender loris is known as kadupapa. In several districts in the Western Ghats, other local names are also used such as bidira mele chigare in Kodagu; alavu in Hassan; uriolu in Dakshina Kannada; and nyala, badanyala, and vanamanushya in Uttara Kannada. The names are not used for any other species.

Morphological Variations in the 2 Subspecies of Slender Loris The general body color is reddish in Loris lydekkerianus malabaricus and gray in L. l. lydekkerianus (Fig. 1a, b). The circumocular patch is very narrow in Loris lydekkerianus lydekkerianus and broad in L. l. malabaricus. As a result, the white rim between the darker preauricular hair and circumocular patch is broad in Loris lydekkerianus lydekkerianus and narrow in L. l. malabaricus. Data on mass and body measurements of 8 individuals are in Table I. The mass of both male (N = 1) and female (N = 1) Loris lydekkerianus malabaricus adults is 180 g, whereas the adult mases of male (N = 2) and female (N = 1) L. l. lydekkerianus are 260 g and 275 g, respectively.


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Fig. 1. (a) Loris lydekkerianus malabaricus; (b) Loris lydekkerianus lydekkerianus.

The head and body length and head breadth are larger in Loris lydekkerianus lydekkerianus than in L. l. malabaricus. We also calculated standard anthropometric indices for relative limb proportions (Jungers, 1985; Table II). Most length-dependent indices including intermembral index, humerofemoral index, brachial index, and hand length index are different

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Kumara, Singh, and Kumar Table I. Body measurements of 2 subspecies of slender loris Loris lydekkerianus lydekkerianus I♂

Ad♂ Ad♂

Loris lydekkerianus malabaricus Ad♀

Mass 175 245 275 275 Chest girth 11.3 13.0 12.3 13.0 Head and body length 20.2 20.3 22.3 22.0 Head Head breadth 3.2 3.5 3.5 3.3 Maximum head length 5.7 6.0 6.4 6.0 Muzzle length 1.1 1.1 1.1 1.1 Ear breadth 1.6 2.0 1.6 1.8 Ear height 2.1 2.2 2.0 2.7 Hand Upper arm length 5.5 6.1 6.5 6.7 Forearm length 6.8 6.5 6.8 7.0 Span of the hand 4.3 4.6 4.5 4.9 Hand length 2.9 2.9 3.1 2.9 Hand breadth 1.3 1.3 N 1.3 Leg Thigh length 6.7 6.9 7.1 7.9 Leg length 6.3 6.6 7.4 7.6 Span of foot 5.9 6.1 6.3 6.1 Foot length 3.3 3.5 4.0 3.7 Foot breadth 1.2 1.3 N 1.5

I♀

I♀

Ad♀

107 105 180 11.6 10.8 9.1 19.0 18.2 19.8

Ad♂ 180 9.7 19.3

2.7 5.8 0.9 1.9 2.5

2.6 5.0 1.2 2.2 2.7

2.7 5.7 1.2 1.3 2.1

2.1 5.2 1.1 1.7 2.5

3.4 5.8 3.7 2.4 1.1

3.6 5.0 3.6 2.3 1.0

5.3 6.8 4.5 3.1 1.1

4.8 6.4 4.3 3.0 1.1

5.3 5.8 5.1 3.1 1.1

5.2 5.6 4.5 2.9 1.0

6.6 6.8 5.9 3.5 1.3

6.7 6.9 6.0 4.0 1.2

Note. The mass of another adult male of Loris lydekkerianus lydekkerianus from Doddaballapura was 376 g. I: immature, weaned but not fully adult (determined on the basis of mass); Ad: adult; N: particular parameter could not be calculated because of injuries. Mass is in g and other measurements are in cm.

between the 2 subspecies. Hence, we confirmed that the subspecies Loris lydekkerianus malabaricus inhabiting the relatively wetter regions of Western Ghats is quite different from L. l. lydekkerianus inhabiting the drier southeastern parts of the state of Karnataka. Distribution of Subspecies of Slender Loris in Karnataka Occurrence of 2 subspecies of slender loris in Karnataka is in Table III and Fig. 2. Loris occurs in some parts (taluks) of Belgaum, Uttara Kannada, Udupi, Shimoga, Chikmagalur, Dakshina Kannada, Hassan, and Kodagu (Fig. 3). The districts lie in the western region of Karnataka, and each has some forests of the Western Ghats hill ranges. The subspecies of slender loris we found in the districts is Loris lydekkerianus malabaricus. The archival records of the District Forest Office revealed absence of lorises in mangrove forests of coastal Karnataka. Lorises are absent in the districts

91.20 91.55 104.62 104.22 2.05 2.20 18.90

93.30 88.40 106.56 96.50 2.00 2.20 18.71

Intermembral index 94.61 Humerofemoral index 82.10 Brachial index 123.64 Crural index 94.00 Forelimb length (mm)/[body 2.20 weight (g)]1/3 Hind limb length 2.30 (mm)/[body Weight (g)]1/3 Hand length index 19.10

Ad♂

Ad♂

Index

I♂

17.47

2.40

88.39 84.80 104.48 96.20 2.11

Ad♀

2.33 20.69

18.54 ± 0.73

21.10

2.29

79.62 69.23 138.89 107.69 1.82

92.00 ± 2.68 82.88 86.71 ± 4.13 64.15 109.80 ± 9.26 170.59 97.73 ± 4.46 109.43 2.09 ± 0.08 1.94 2.27 ± 0.09

I♀

20.39

2.37

90.30 80.30 128.30 103.03 2.10

Ad♀

21.2

2.39

82.60 71.43 134.74 103.00 2.00

Ad♂

Mean

20.85 ± 0.38

2.34 ± 0.04

83.85 ± 4.55 71.28 ± 6.74 143.13 ± 18.66 105.79 ± 3.28 1.97 ± 0.12

Loris lydekkeriannus malabaricus I♀

Mean

Loris lydekkeriannus lydekkeriannus

Table II. Standard anthropometric indices of relative limb proportions (Jungers, 1985) for 2 subspecies of slender loris

Loris lydekkerianus in Karnataka, India 949

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Table III. N

Occurrence of 2 subspecies of slender loris in different districts and taluks of Karnataka District

Sub-species

Taluks with loris — — — —

1 2 3 4 5 6

Bidara Gulbargaa Bijapura Bagalkota Belgaumb Uttara Kannadab

Absent Absent Absent Absent L. l. m L. l. m

7 8 9 10 11 12 13 14

Dharwada Gadaga Koppala Raichura Bellarya Davangerea Haveria Shimogab

Absent Absent Absent Absent Absent Absent Absent L. l. m

15 16

L. l. m L. l. m

17

Udupib Dakshina Kannadab Chikmagalurb

18 19 20 21

Chitradurgaa Tumkura Hassanb Kodagub

Absent L. l. l L. l. m L. l. m

22 23 24 25

Mysorec Chamarajnagarc Mandyac Bangalorec

Absent L. l. l L. l. l L. l. l

26

Kolarc

L. l. m

L. l. l

Khanapura (1) Supa (2), Haliyala (3), Karwar (4), Yellapur (5), Mundgod (6), Sirsi (7), Ankola (8), Kumta (9), Siddapur (10), Honnavara (11), Bhatkala (12) — — — — — — — Soraba (13), Sagara (14), Hosanagara (15), Tirthahalli (16), Kundapura (17), Karkala (18) Belthangady (24), Puttur (25), Sullia (26) Narasimharajapura (19), Koppa (20), Sringeri (21), Chikmagalur (22), Mudigere (23) — Kunigal, Tumkur, Sakaleshapura (27), Alur (?) (28) Somvarpet (29), Madikeri (30), Virajendrapet (31) — Kollegala Malavalli (?), Maddur Anekal, Bangalore, Kanakapura, Magadi, Nelamangala, Dod Ballapura, Hoskote, Channapatna (?), Ramanagaram (?), Devanahalli (?) Malur, Bangarpet, Kolar, Mulbagil, Srinivasapura, Chinthamani, Sidlaghatta (?), Chikballapura, Gudibanda

Note. N: map locations in Fig. 2; L. l. l.: Loris lydekkerianus lydekkerianus, L. l. m.: Loris lydekkerianus malabaricus; (?) = no sighting/no proper information available on the presence of slender loris. Numbers in parentheses indicate map location in Fig. 3. a Plains. b Western Ghats. c Plateau.


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Fig. 2. Map of the state of Karnataka with distribution of the 2 subspecies of slender loris. Numbers indicate districts (see Table III for names of districts)

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Fig. 3. Map of the distributional range of Loris lydekkerianus malabaricus in the western districts of Karnataka. Numbers indicate taluks (see Table III for names of taluks). BE: Belgaum; UK: Uttara Kannada; SH: Shimoga; UD: Udupi; CH: Chikmagalur; DK: Dakshina Kannda; HA: Hassan; KO: Kodagu. I: BrahmagiriMakut; II: Pushpagiri-Bisle; III: Sirsi-Honnavara.


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of Bidar, Gulbarga, Bijapur, Bagalkot, northern and eastern Belgaum, Dharwad, Gadag, Koppal, Raichur, Bellary, Davangere, Haveri, northern and eastern Shimoga, eastern Chikmagalur, Chitradurga, northern and western Tumkur, eastern Hassan, Mysore, southern and western Chamarjnagar, western Mandya, and northern and western Tumkur. The vegetation in the regions is sparse and dry. Lorises occur in some eastern parts of the districts of Mandya, Bangalore (Rural), Kolar, outskirts of Bangalore (Urban), southeastern Tumkur, and some parts of Chamarajnagar districts (Fig. 4). The Eastern Ghats hill ranges cross through some parts of these districts, and the forests are relatively dry. The subspecies of slender loris in these eastern districts is Loris lydekkerianus lydekkerianus.

Fig. 4. Map of the distributional range of Loris lydekkerianus lydekkerianus in the southeastern districts of Karnataka. Numbers indicate taluks (see Table VII for names of taluks). TU: Tumkur; BA: Bangalore; MA: Mandya; CH: Chamarajnagar; KO: Kolar

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Loris lydekkerianus malabaricus Relative Abundance of Loris lydekkerianus malabaricus in Different Regions of the Western Ghats Table IV contains data on relative abundance of Loris lydekkerianus malabaricus in different regions of the Western Ghats and its adjacent forests. We sighted 63 slender lorises in 293 km of survey in rain forests, for an overall encounter rate of 0.215 individuals/km. The encounter rate was 0.22, 0.29, and 0.13 individuals/km in Brahmagiri-Makut, PushpagiriBisle, and Sirsi-Honnavara respectively, and it varied significantly among study sites (G = 7.25; df = 2; p < 0.01: G statistics, Sokal and Rohlf, 1995). A survey of 181 km in the forests of Rajiv Gandhi National Park and Nugu Wildlife Sanctuary, which are adjacent to the Western Ghats, revealed no slender lorises.

Relative Abundance of Loris lydekkerianus malabaricus in Different Forest Types We classified the forest types of each study area on the basis of stand structure. We considered the rain forest without much disturbance, consisting of shrubs and trees of height >20 m and with continuous vegetation from lower to higher canopy, as intact evergreen forest, and the disturbed forest without continuity from lower to higher canopy as degraded evergreen forest. The vegetation in the rain forest toward hilltops becomes stunted and patchy, and we considered such forest as evergreen forest scrub. We considered the relatively drier forest adjacent to the rain forest as moist deciduous forest. We also surveyed coffee and cardamom plantations adjacent to the forests. Coffee plantations had forest trees as shade trees, whereas cardamom plantations had no bushes and small trees, and only tall trees remained as shade trees to grow cardamom underneath. All 3 areas had intact evergreen forests, evergreen forest scrub, and degraded evergreen forests. Plantations were at Brahmagiri-Makut and Pushpagiri-Bisale, and moist deciduous forests were at Sirsi-Honnavara. Our efforts (km walked) for the survey in each forest type changed depending on the extent of a forest type and feasibility of access. Table V contains data on slender lorises in different forest types of the 3 study areas in the Western Ghats. The relative abundance of slender lorises in different forest types differed significantly (G = 15.01; df = 4; p < 0.005). The highest encounter rate (0.47 individuals/km) was in plantations, especially cardamom, followed by evergreen forest scrub (0.34 individuals/km) and degraded

Forest type

Rainforest (Mesua ferrea–Palaquium ellipticum) Rainforest (Mesua ferrea–Palaquium ellipticum) Rainforest (Persea macrantha–Diospyros spp. –Holigarna spp.) Moist deciduous forests (Tectona–Dillenia– Lagerstroemia series) and dry deciduous forests (Terminalia– Anogeissus–Tectona series) Dry deciduous scrub

Note. All regions surveyed on foot

Nugu Wildlife Sanctuary (76◦ 26 –76◦ 28 E,11◦ 52 – 11◦ 59 N)

Rajiv Gandhi National Park (76◦ 00 –76◦ 17 E,11◦ 51 – 12◦ 15 N)

Sirsi-Honnavara (74◦ 35 – 74◦ 47 E,14◦ 15 –14◦ 25 N)

Brahmagiri-Makuta (75◦ 50 –760 3 E, 12◦ 5 –12◦ 13 N) Pushpagiri-Bisale (75◦ 38 – 75◦ 42 E,12◦ 34 –12◦ 52 N)

Area

1000

1000—1500

60

121

119

123

6000 5000

51

km covered

6000

Rainfall (mm)

0

0

16

36

11

No. of slender lorises

—

—

0.13

0.29

0.22

Individuals/km

Table IV. Loris lydekkerianus malabaricus in different regions of Western Ghats and its adjacent forests of Karnataka


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Kumara, Singh, and Kumar Table V. Loris lydekkerianus malabaricus in different forest types of Western Ghats of Karnataka Forest type Intact rain forest Rain forest scrub toward hilltop Moist deciduous Degraded rain forest Cardamom plantation Total

km covered 186.0 23.7 17.0 27.8 38.5 293.0

No. of slender lorises Individuals/km 28 8 2 7 18 63

0.15 0.34 0.12 0.25 0.47 0.21

Note. All forest types surveyed on foot.

evergreen forest (0.25 individuas/km). The encounter rate was very low in intact evergreen forests and moist deciduous forests. Data on sightings of slender lorises in trees of different heights and at various heights in the trees are in Fig. 5. Though slender lorises were present in trees of all heights, they were mostly (43.10%) in 6–10 m trees. The heights of individuals in trees were < 10 m (ca. 80%), though we found them at all heights.

Relative Abundance of Loris lydekkerianus malabaricus at Different Altitudes We surveyed an area of 50–1750 m asl in the forests of the Western Ghats, which allowed us to determine the relative abundance of slender lorises at different altitudinal ranges. We encountered slender lorises at rates 0.10, 0.19, and 0.52 individuals/km at altitudes of < 500 m, 500–700 m, and >700 m respectively (Table VI); the relative abundance of slender lorises thus significantly increased as altitude increased (G = 34.39; p < 0.001). All sightings of slender lorises occurred between 55 m asl and 933 m asl only. Loris lydekkerianus lydekkerianus We found Loris lydekkerianus lydekkerianus in 5 southeastern districts of Karnataka—Tumkur, Bangalore (Rural), Kolar, Mandya, and Chamarajanagar (Fig. 2). However, because of local restrictions and limitations, we were able to carry out intensive surveys only in the first 3 districts. In Mandya, slender lorises were present only in a few patches adjoining large forest areas of Bangalore and Tumkur. We obtained information from Chamarajanagar from forest personnel and villagers during the day because police and Forest Department prohibited entry into the forests

Fig. 5. Height utilization in the two subspecies of slender lorises (N = 59 for Loris lydekkerianus malabaricus; N = 84 for Loris lydekkerianus lydekkerianus).


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Kumara, Singh, and Kumar Table VI.

Loris lydekkerianus malabaricus in different altitudinal range of Western Ghats, Karnataka

Altitude m asl 700

km covered

No. of slender lorises

Individuals/km

157.5 68.4 67.1

15 13 35

0.10 0.19 0.52

Note. All altitudes surveyed on foot.

at night owing to fear of forest bandits. Cauvery Wildlife Sanctuary is the only protected area within the distributional range of the subspecies in Karnataka, but we sighted no slender loris in the Sanctuary.

Relative Abundance of Loris lydekkerianus lydekkerianus in Different Districts During a 318-km survey in Tumkur, Bangalore, and Kolar, we sighted 90 slender lorises, for an encounter rate of 0.28 individuals/km (Table VII). However, excluding the taluks without slender lorises, the areas slender lorises actually occupy (ca. 218 km) provide an encounter rate of 0.41 individuals/km. The encounter rate in Tumkur, Bangalore, and Kolar is 0.31, 0.26, and 0.33 individual/km, respectively. Because the slender lorises occur in only a few taluks of each district, the encounter rate in the areas actually occupied is 0.45, 0.32, and 0.51 individuals/km in Tumkur, Bangalore, and Kolar respectively (Fig. 4). Among the taluks, Malur (1.29 individuals/km), Magadi (0.69 individuals/km), Nelamangala (0.43 individuals/km), and Kunigal (0.51 individuals/km) have relatively higher abundance of slender lorises.

Relative Abundance of Loris Lydekkerianus lydekkerianus in different forest types Depending on the stand structure, we classified the forests of this region as deciduous with no undergrowth, mixed deciduous, Acacia dominated, scrub with stunted vegetation, degraded open scrub, plantations (mango, tamarind, coconut, Acacia or Eucalyptus), and village/cultivated lands. Lorises are absent in deciduous forests lacking undergrowth and degraded open scrub (Table VIII). In other vegetation types, the encounter rates vary significantly (G = 18.51; df = 4; p < 0.01). We encountered

Loris lydekkerianus in Karnataka, India Table VII.

959

Relative abundance of Loris lydekkerianus lydekkerianus in different districts of Karnataka Taluks

Tumkur

Kunigal (1) Tumkur (2) Madhugiri (3) Chikkanayakanahalli (4) Sira (5) Total Kanakapura (6) Ramanagaram (7) Channapatna (8) Magadi (9) Nelamangala (10) Doddaballapura (11) Hoskote (12) Total Malur (13) Bangarapet (14) Mulbagal (15) Kolar (16) Srinivaspura (17) Chintamani (18) Chikballapura (19) Gauribidanur (20) Bagepalli (21) Total 19.0

43.0 30.0 14.0 12.0 6.0 105.0 35.0 4.5 12.0 17.5 14.0 9.0 10.0 102.0 17.0 15.0 7.0 6.0 15.0 4.0 5.0 14.0 9.0 92.0 0

22 11 0 0 0 33 3 0 0 12 6 2 4 27 22 5 1 0 1 0 1 0 0 30 —

0.51 0.37 — — — 0.31 0.09 — — 0.69 0.43 0.22 0.40 0.26 1.29 0.33 0.14 — 0.07 — 0.20 — — 0.33

Grand total

318.0

90

0.28

Bangalore

Kolar

Cauvery wildlife sanctuary

km covered

No. of slender lorises Individuals/km

Districts

Note. All regions surveyed by vehicle. Numbers in parentheses indicate places in Fig. 4.

slender lorises at a relatively higher rate in plantations and in villages/cultivated lands. Data on sightings of slender lorises in different types of trees are in Table IX. Though slender lorises were in a wide variety of trees, the highest percentage of sightings (38.89) is in various species of Acacia. Of the cultivated plants, tamarind (Tamarindus indica) accounted for a next highest percentage of sightings (15.55%). More than 84% sightings of slender lorises were in trees of