Sloth Bear: The Barefoot Bear of Sri Lanka (Preview)

The Barefoot Bear of Sri Lanka

The Barefoot Bear of Sri Lanka

Shyamala Ratnayeke, Luxshmanan Nadaraja

Copyright © 2022 by Sunway University Sdn Bhd Published by Sunway University Press An imprint of Sunway University Sdn Bhd No. 5, Jalan Universiti Bandar Sunway 47500 Selangor Darul Ehsan Malaysia press.sunway.edu.my All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, now known or hereafter invented, without permission in writing from the publisher.

978-967-5492-25-9 Perpustakaan Negara Malaysia

Cataloguing-in-Publication Data

Shyamala Ratnayeke Sloth Bear: The Barefoot Bear of Sri Lanka / Shyamala Ratnayeke; photography by Luxshmanan Nadaraja.

ISBN 978-967-5492-25-9 (hardback) 1. Sloth bear--Sri Lanka.

2. Sloth bear--Behavior--Sri Lanka.

3. Sloth bear--Conservation--Sri Lanka.

I. Luxshmanan Nadaraja.

II. Title.

599.78095493

Edited by Sarah Loh, Hani Hazman Designed and typeset by Rachel Goh Printed by Vinlin Press Sdn Bhd, Malaysia

All photos in this book are by Luxshmanan Nadaraja with the exception of those that have been kindly provided by Tony Nadaraja, Nuwan Bandara Diyawe, Palitha Antony, and Arrenga Nadaraja.

Every reasonable effort has been made to trace the copyright holders and obtain their permission to reproduce copyright material. Any errors or omissions are not intentional and we would be happy to correct them if brought to our attention.

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WILPATTU (Photo by Arrenga Nadaraja)

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MODERAGALA, YALA

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KUMANA

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KUMANA

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WILMITIYA, WASGAMUWA

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About the Authors SHYAMALA ratnayeke,

PhD, conducted the first focused field study on the subspecies of sloth bear found in Sri Lanka. She has been associated with research on Asian bears and other carnivores for more than 20 years. She has served on the IUCN Bear Specialist Group, and on the Council and the Research and Conservation Grants Committee of the International Association for Bear Research and Management for several years. In her current role as associate professor at Sunway University, she teaches courses in biology and conducts research on the Malayan sun bear and other carnivores.

is a leading Sri Lankan wildlife photographer who has published and co-authored a number of books on the nature, archaeology, and culture of Sri Lanka.

He is founder and CEO of the studio Wildlight (Pvt) Ltd, Sri Lanka.

Luxshmanan Nadaraja

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Contents Foreword Preface 1 Natural History of the Sloth Bear and Cultural Perspectives

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2 The Distribution of the Sloth Bear

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3 The Ecology of the Sloth Bear

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4 Sloth Bears as Surrogates for Carnivore Conservation

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5 Conflicts Between Humans and Sloth Bears

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6 A Future for the Sloth Bear

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Acknowledgements

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References

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Index

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Foreword As one of the most charismatic families of mammals, bears elicit a wide range of emotions among humans, ranging from pure fascination to reverence to innate fear. The sloth bear perhaps embodies the reasons for these human emotions more than any bear species in the world. Its long, shaggy fur, endearing face, and ambling gait create an almost whimsical appearance—a stark contrast to its sometimes aggressive response in sudden encounters or when provoked, unleashing a surprising combination of speed, strength, and ferocity. Sloth bears can stand their ground against formidable opponents, and many a leopard or tiger probably wished they had never run into this fuzzy ball of terror.

This temperament is also well known among villagers who live in sloth bear range and tragically experience human injuries and even fatalities from sloth bear attacks.

As a consequence, many sloth bears are killed in encounters, even when there is no direct threat. Few species pose a greater challenge to wildlife conservation than the sloth bear, particularly in rural regions where subsistence living is the norm.

Any progress towards enhancing the long-term viability of Sri Lanka’s sloth bears requires understanding their biology and ecology as well as a thorough knowledge of human attitudes and perceptions towards a species that literally affects their livelihoods.

In this inspiring book, Dr Shyamala Ratnayeke describes her scientific journey to better understand this charismatic bear species of her native Sri Lanka, intending to improve its chances of survival in a human-dominated landscape. This is the journey of a determined and dedicated wildlife researcher, motivated by her early exposure to nature while growing up on a tea plantation and her family’s love of Sri Lanka’s spectacular wildlife, landscapes, and cultural heritage. Following her desire to become an ecologist, Dr Ratnayeke began her journey studying the behaviour of toque macaques at the Smithsonian Primate Project in Sri Lanka for her graduate degree, followed by a PhD project on raccoons at Oak Ridge National Laboratory through the University of Tennessee, Knoxville, where our career paths crossed in the early 1990s. At the time, I was studying American black bears in Great Smoky Mountains National Park, which was the start of a scientific career focused on large carnivores and culminating with my current research on the Yellowstone grizzly bear population.

In the late 1990s, Dr Ratnayeke and I started collaborating on wildlife projects, a research partnership that continues today. After earning her PhD, she accepted an Assistant Professor position at Spelman College in Atlanta and started laying the groundwork for the sloth bear project with funding from the United States

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National Science Foundation. After completion of field studies, she focused on publishing the findings, as her career path led her back to Atlanta to teach at the newly established Georgia Gwinnett College, followed by a faculty position at the University of Dodoma in Tanzania on a United States Fulbright Scholarship, where she studied various small carnivores.

In her current position at Sunway University in Kuala Lumpur, Malaysia, she established a successful research programme on Malayan sun bears, in collaboration with the Bornean Sun Bear Conservation Centre in Sabah. These unique and broad experiences of a seasoned field ecologist are reflected in this book, in which Dr Ratnayeke presents the reader with comprehensive and expert insights from her studies on the ecology of sloth bears and their relationship with humans.

Similar to challenges other female scientists face while conducting pioneering work, leading the sloth bear project required a strong will and skilful navigation of gender barriers in a male-dominated profession. Additionally, at a time when wildlife research in Sri Lanka was not a high priority, numerous administrative and bureaucratic hurdles required creativity, flexibility, and especially patience. Yet with a clear focus and pragmatic determination, Dr Ratnayeke persevered in her pursuits to fully understand the ecology and conservation context of sloth bears in this small island nation.

I have been fortunate to collaborate on studies of bear species across the globe, and the Sri Lankan sloth bear studies will forever hold a special place in my heart.

Very little was known at the time about sloth bears, which made Dr Ratnayeke’s studies particularly exciting and important, with discoveries waiting at every turn.

Visiting the project in 2002, I marvelled at the unique features of these animals as we captured and radio-collared sloth bears for one of the first wildlife telemetry studies in Sri Lanka. It was fascinating to witness the specialised adaptations of sloth bears that allow them to forage efficiently for termites, features that are radically different from other bear species. The telemetry data revealed important details of sloth bear ecology, including some of the smallest home ranges reported for any bear species. This was a promising indication that even relatively small protected areas may play an important role in the persistence of sloth bear populations. These discoveries are eloquently captured in this book through the eyes of an accomplished field ecologist.

As we travelled the Sri Lankan countryside examining bear habitat and protected areas, I contemplated various conservation perspectives. I remember wondering how, in a small country with high human densities, all 14 native species of Carnivora are still present as well as Asian elephants, five primate species, and a high diversity of smaller mammals. A partial, but important, answer is likely cultural: respect for all forms of animal life and forest habitat was deeply enshrined in Sri Lanka’s ancient moral and even legal codes, and remains a way of life in

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this culturally rich country. Indeed, despite the sometimes tragic consequences of sloth bear encounters, surveys by Dr Ratnayeke and her team indicated that a majority of rural Sri Lankans living in or near bear habitat believe that sloth bears are an integral part of forests and their legal protection is warranted. This is truly remarkable and presents an opportunity to improve perceptions of sloth bears and build support for their conservation.

The sloth bear has long remained somewhat of an enigma, particularly outside of its native range in the Indian subcontinent. Richly illustrated with images from Sri Lanka’s premier wildlife photographers, this book encapsulates the wealth of information obtained from Dr Ratnayeke’s studies and reveals the fascinating biology and ecology of this species to a broad audience. This book presents not just a scientific journey but also a story of hope for the conservation of this remarkable species.

I hope that the knowledge gained from these studies will help reduce bear attacks among villagers who are dependent on forest resources, that the protected area network currently safeguarding and connecting much of sloth bear range in Sri Lanka will remain intact to provide continuing security, and that those same areas will help preserve Sri Lanka’s magnificent biodiversity.

In a country where more than 80% of residents live in rural areas and after decades of internal conflict, improving the lives of rural people is crucial to reduce human pressures on the forest ecosystems that serve as the backbone of this biodiversity.

Thus, above all, I hope this book inspires conservation action that considers the livelihoods of people in rural communities, as they are intricately intertwined with the fate of sloth bears, and all of Sri Lanka’s wildlife.

Frank T. van Manen, PhD Team Leader, Interagency Grizzly Bear Study Team US Geological Survey, Northern Rocky Mountain Science Center Bozeman, Montana, United States

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Preface The idea of this book originated in the 1990s, when I was in the latter stages of my doctoral degree at the University of Tennessee, Knoxville. At the time, biologists in Nepal and India had begun pioneering work on sloth bears using capture and radio telemetry. Until then, most of what we knew about sloth bears came from brief surveys, natural history observations, and anecdotes. Data on the distribution, population status, and ecology of most species of Asian bears was still rudimentary compared to what was known about bears in North America and Western Europe.

The distribution range of bears in tropical Asia is believed to have declined drastically in the last five decades with population trajectories expected to parallel the loss of bear habitat. This gap led to an increased interest in Asian bears and to my decision to return to Sri Lanka to work on the sloth bear.

At least three years transpired between raising funds for the project and starting work. Professor Mike Pelton, my doctoral advisor who led the most extensive research programme on American black bears in the Southeastern United States, enthusiastically backed the project. Frank Teunissen van Manen and I decided to collaborate, creating a partnership that has endured to this day. I visited Sri Lanka in 2000 to conduct a short feasibility study and in 2002, I returned to start work in earnest.

How sloth bears evolved to their current form and temperament is a topic of much speculation among biologists. Lacking the stealth, speed, and killing prowess of large cats, sloth bears are well adapted for feeding on termites, honey, and fruit, and go about their day-to-day business with little apparent concern for the dangers and distractions in their environment. Yet, they have an extremely tenuous relationship with rural human communities that fear bears for good reason. Human fear leads to persecution of the source, and the history of predator-control programmes confirms this. Today, under state protection, legal persecution of sloth bears no longer occurs. Yet, as I have laid out in this book, human-induced mortality may be as great a threat to bears as the gradual erosion and fragmentation of remaining bear habitat.

This book synthesises the body of published research on sloth bears in Sri Lanka.

I have done my best to deliver the information in a less technical style, and to add the types of personal experiences, perspectives, and imagery that rarely appear in scientific journals. For those who want the technical details, I provide several references on matters related to bears. In this book, I present ecological, behavioural, and conservation-related information about sloth bears alongside Luxshmanan Nadaraja’s footage of Sri Lanka’s unique biodiversity and cultural

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heritage. Luxshmanan’s photography is the result of a lifetime connected to the wildlife and nature of Sri Lanka and a profound understanding of the subjects that compose his pictures. Other notable Sri Lankan nature photographers have also contributed to this book.

An overarching goal of this book is conservation and I say little about the climate for wildlife research in Sri Lanka, which was dire during the tenure of my study in the early 2000s. The challenges I encountered might have been insurmountable had it not been for the decency of senior colleagues who wished to enable and encourage scientific research and who tried their best to help. Nevertheless, I was ready to shift focus when some doors closed, which led to the first islandwide survey of sloth bear distribution and a comprehensive study of human-sloth bear conflict.

Our ability to solve problems in conservation comes from asking questions that matter, and my advice to future wildlife biologists is to find creative ways to work within the limitations you encounter. I have been challenged that what I did was impossible. My response is that it was indeed possible because there is more than one way to achieve an objective and I went about my work reflectively, but also with single-minded determination, discipline, and focus.

Science is only part of the conservation toolbox, but it can provide crucial insights to aid conservation, particularly for large mammals in tropical Asia that are being driven to extinction by the ceaseless tide of advancing humanity. Few species symbolise wilderness as much as the sloth bear, which has retreated to those parts of the country least touched by the trappings of modern civilisation. The variety of species that occupy our wilderness cannot speak for themselves and what we know about the majority is far from comprehensive. It is our job to better understand what it takes for sloth bears to thrive and for human-sloth bear coexistence to be realised. This is especially important in Sri Lanka where no habitat is entirely free of the human footprint.

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Sloth Bear: The Barefoot Bear of Sri Lanka

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Natural History of the Sloth Bear and Cultural Perspectives

It is August in the dry-zone forests of Sri Lanka. The rains have ceased, and hot, dry winds have parched the grass and dried many of the smaller waterholes and stream beds. Some of the resident elephant herds remain, but many have moved to regions where water and fodder are more plentiful. The deer and buffaloes seem abundant on the plains, the forests rich with bird life, and the occasional leopard may be seen reclining lazily at the edge of the jungle. Less obvious to either casual or seasoned visitors is the dark and shaggy sloth bear that frequents the shadows of the rock outcrops and the ancient stands of palu and weera trees of the dry-zone forests. It travels mostly at night, using the dense cover of thickets to escape searing daytime temperatures. This elusive and little-known bear of Sri Lanka is the focus of this book.

Left A cool splash on a hot day (Photo by Tony Nadaraja)

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Sloth Bear: The Barefoot Bear of Sri Lanka

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1 Natural History of the Sloth Bear and Cultural Perspectives

Taxonomic Relationships Sloth bears (Melursus ursinus) belong to the order Carnivora, a group of mammals with a predatory or flesh-eating ancestry (and of growing conservation concern). Modern Carnivora are not exclusively predatory and have diversified into a variety of feeding niches. The Ursidae, or bear family, for example, includes the highly carnivorous polar bear (Ursus maritimus), the predominantly bamboo-eating giant panda (Ailuropoda melanoleuca), and other species of bear that possess very generalised diets.

The bear family comprises just eight species, of which seven occur in the Northern Hemisphere (Kitchener, 1994). The giant panda forms the oldest branch of the ursid phylogeny, followed by the spectacled bear of South America, Tremarctos ornatus (O’Brien et al., 1985). These two species form the oldest taxa of the ursid lineage. Evolutionary relationships among the six more recently evolved ursids (subfamily Ursinae) have been difficult to resolve, apart from the speculation that their radiation occurred two to four million years ago, possibly in Central Asia (Hunt, 1996).

Recent phylogenetic analyses using all currently available sequence data, including whole mitochondrial genome sequences, have provided more resolving power. The analyses suggest that the sloth bear line was the first to diverge from the other five ursine species approximately four to six million years ago (Yu et al., 2007; Nyakatura & BinindaEmonds, 2012). Sloth bears, therefore, may have evolved well before the Pleistocene and the arrival of hominids in Central Asia.

Global Distribution

Left A sloth bear with a rather inconspicuous chest mark (top), previously thought to be characteristic of sloth bears from Sri Lanka, which led to the name “inornatus” for this subspecies. The chest mark is quite variable among sloth bears on the island, with some possessing a conspicuous V-shaped chest mark (bottom). Sloth bears are more likely to be active during the day in protected areas than where forest cover is sparse and where human densities are greater.

Sloth bears radiated from an ursine ancestor in Asia (Hunt, 1996) and evolved in the Indian subtropics (Kurten, 2007). Currently, they are found in the lowlands of India, Nepal, and Bhutan, with one subspecies, Melursus ursinus inornatus, on the island of Sri Lanka (Pocock, 1941). The sloth bear has disappeared from much of its former range, owing mostly to the conversion of forests to other forms of land use. It may no longer persist in small forest fragments or in degraded, unprotected forests.

The vast majority of sloth bear range remains in India, where the bears occupy suitable habitats throughout the peninsula and up to the Himalayan foothills, where the range overlaps with that of the Asiatic

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Sloth Bear: The Barefoot Bear of Sri Lanka

Global distribution of the sloth bear in recent decades showing areas where sloth bears are confirmed as present (extant), or possibly present (Adapted from Dharaiya et al., 2016)

LEGEND Extant Possibly extant Presence uncertain

N

0

250

500

1,000 Kilometres

black bear, Ursus thibetanus (Johnsingh, 2003). Reliable density estimates are unavailable, but the largest populations probably occur in the foothills of the Western Ghats and the Central Highlands of India (Yoganand et al., 2006).

Species Description Sloth bears differ from other ursine bears by their markedly shaggy appearance and long, ivory-coloured claws, lending a superficial resemblance to true sloths (Folivora) which belong to an entirely different mammalian lineage, the Xenarthra. In fact, the first scientific description of the sloth bear, Bradypus ursinus, described the specimen as a bear-like sloth: “Ursine Bradypus” or “Ursiform Sloth” (Shaw,

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1 Natural History of the Sloth Bear and Cultural Perspectives

1791; as cited in Erdbrink, 1953). The most critical feature leading to the mistaken identity was the lack of a central pair of maxillary incisors in the sloth bear, which is a true sloth-like characteristic.

True sloths, which are entirely New World in origin and distribution, are slow-moving, arboreal creatures that typically hang upside down from branches (although giant ground sloths existed in fossil records).

Meyer (1793) was the first to recognise that the sloth bear was a bear and not a sloth, naming the bear Melursus lybius (as cited in Erdbrink, 1953). Sloth bears possess postcranial, cranial, and dental features characteristic of the bear family (Hunt, 1996), including large bodies supported by stout legs, small eyes and ears, a short tail, and plantigrade feet.

A sloth bear flaring its lips, displaying the missing central maxillary incisors and vaulted upper palate that aid with suction feeding (Photo by Nuwan Bandara Diyawe)

Bears, in general, have large heads relative to body size. In the sloth bear, the abundance of long, coarse hair on the ears, neck, and shoulders further accentuate the size of its massive head and heavily built forequarters. The coat in sloth bears may vary from a deep to dull black, rarely dark brown. The coat generally lacks underfur, with the longest hair on the back and sides of the neck (up to 18

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Sloth Bear: The Barefoot Bear of Sri Lanka

centimetres in some specimens) as well as the shoulders. The whitish hair covering the muzzle is extremely short and a light brown or whitish V-shaped chest mark is characteristic of the sloth bear. On the Indian mainland, weights typically range from 70–145 kilogrammes for adult male sloth bears and 50–95 kilogrammes for adult females (Garshelis et al., 1999).

Sloth bears have evolved unique morphological characteristics for feeding on termites. The missing pair of central maxillary incisors are just one of several adaptations for myrmecophagy using suction.

Other specialisations include large protrusible lips, the ability to seal their nostrils shut, and palates that are longer, broader, and more vaulted than any other species of bear (Erdbrink, 1953). Their heavily built forelimbs, armed with long, strong, and laterally flattened ivorycoloured claws, are capable of breaking through rotting logs and hard termite mounds.

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Sloth bears have long, loose, and highly protrusible lips that aid suction feeding by forming a sucking tube. The upper part of the rhinarium projects forward and is used to seal the nostrils shut when feeding on termites.

(Photo by Nuwan Bandara Diyawe)

1 Natural History of the Sloth Bear and Cultural Perspectives

A glimpse of the sloth bear’s bare foot pad showing the fused digital pads, lying in an almost-straight line. There is no hair between the digital and plantar pads.

Their premolars and molars are small in comparison with other bears, possibly because their partly insectivorous diet has reduced the need for large, grinding surfaces to break down vegetable matter (Sacco & van Valkenburgh, 2004). Honey and meat are also consumed, and vegetable matter—especially seasonally abundant fruit—may compose 70% to 90% of their diet depending on location and season.

Sloth bears are good climbers, but they climb mostly to reach ripened fruit or honey. Much of their feeding, resting, and travelling occur on the ground. The foot pads of sloth bears differ from other bears—they are entirely hairless on the undersurface, with the five digital pads fused and arranged in an almost-straight line. While walking, the sloth bears’ forefeet conspicuously rotate medially or inward, so that the footprints face almost perpendicular to the path of movement. This tendency has led more than a few rural hunters to believe that the sloth bear deliberately confuses humans about its direction of travel.

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Sloth Bear: The Barefoot Bear of Sri Lanka

Typically solitary, sloth bears may form small family groups consisting of an adult female with cubs, pairs of young siblings that have been recently separated from their mothers, or mating aggregations where several males may accompany a female in oestrus. Relatively little is known about their reproductive behaviour, especially for populations at the southern end of the distribution range. Females give birth in dens where they remain without emerging to feed for 6–10 weeks.

Cubs remain with their mothers for up to two and a half years before separating (Joshi et al., 1999). Females carry cubs on their backs for six to seven months, a characteristic shared with anteaters and possibly related to myrmecophagy; more plausibly, this characteristic may serve to safeguard the young from predation by tigers and leopards (Joshi et al., 1999).

The Subspecies of Sloth Bear Sri Lanka constitutes the southernmost limit of the sloth bear’s global range and is an important biodiversity hotspot. Marked variation in climate and topography has led to the establishment of diverse

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A sloth bear cub displaying the typical mode of travel during its first six months. Female sloth bears are fiercely protective of their cubs.

1 Natural History of the Sloth Bear and Cultural Perspectives

vegetation communities and fauna, including more than 941 species of vertebrates, of which approximately 40% are endemic (Gunawardene et al., 2007). Sri Lanka (65,610 square kilometres) lies to the south of India between 5°55’ to 9°50’ N and 79°42’ to 81°52’ E. A bridge of shallow water called the Palk Strait lies between Sri Lanka and India, and periodic land connections between the two land masses occurred during the Pleistocene (2.6 million years to 11,700 years ago) and as recently as the Holocene interglacial period (7,000 years ago). These connections facilitated faunal exchange with India and have undoubtedly influenced the present distribution of life forms on the island (Cooray, 1984; Kulatilake, 2016).

The sloth bear comprises two subspecies: Melursus ursinus ursinus occurs on the Indian mainland, whereas Melursus ursinus inornatus is endemic to Sri Lanka and the only species of bear on the island (Dharaiya et al., 2016). The Sri Lankan subspecies is smaller on average and has a sparser, shorter coat, with hair rarely exceeding 8–13 centimetres (Pocock, 1941), oftentimes shorter. Its longest claws are on the forefeet (the third digit), about 5–6 centimetres in length along the curve, whereas claws on the hind feet are 3–4.5 centimetres.

Surprisingly, few morphological data are available in a form that allows for reliable comparisons between the two subspecies. Adult males at Wasgamuwa National Park, Sri Lanka weigh 70–85 kilogrammes and adult females weigh 54–67 kilogrammes. Both sexes of the Sri Lankan subspecies possess smaller body measurements, except for their tails, which are longer than the Indian (or mainland) subspecies (Table 1.1). The shorter tail length of the Indian subspecies (Pocock, 1941) might be an artefact of how this was measured, but it merits further verification.

Phillips (1984) reported a body weight of 104 kilogrammes for Sri Lankan male bears and 68 kilogrammes for females, with shoulder heights of 91 centimetres (3 feet) and 61 centimetres (2 feet) respectively. It is not known, however, if these are the maximum weights or averages. Phillips received the measurements from a third party and the shoulder height may have reflected a single unusually large male, or the estimate might be erroneous (Pocock, 1941). Apart from this possible anomaly, the body measurements of the Indian subspecies are almost identical to those of the Sri Lankan subspecies reported by Phillips (Table 1.1). Neither Phillips nor Pocock described how these measurements were taken and thus, the comparisons of body measurements should be interpreted with caution because measurements made over curves are greater than those between pegs.

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Sloth Bear: The Barefoot Bear of Sri Lanka

Table 1.1 Body mass, head-body length, tail length, and shoulder height of adult male (M) and adult female (F) of the Indian subspecies (M. u. ursinus) and the Sri Lankan subspecies (M. u. inornatus)

Sex

N

Body Mass (kg)

Head-body length (cm)

Tail length (cm)

Shoulder height (cm)

M

4

-

156

8

79

F

1

-

138

5

61

M

-

80–145

-

-

-

F

-

55–95

-

-

-

M

5

-

155

14

91

F

6

-

140

15

61

M. u. inornatus (Sri Lanka)

M

-

104

-

-

-

F

-

68

-

-

-

M. u. inornatus (Wasgamuwa National Park, Sri Lanka)

M

5

70–85

150 a

13 b

68 c

F

3

54–67

138 a

14 b

62 c

Source

Species (Locality)

Pocock (1941)

M. u. ursinus (India)

Garshelis et al. (1999)

M. u. ursinus (India)

Pocock (1941) (received from W. W. A. Phillips)

M. u. inornatus (Sri Lanka, multiple locations)

Phillips (1984) Ratnayeke et al.

(2007a)

Note: N denotes the number of bears contributing to a measurement; dashes indicate no data a Over curves, bear lying on side, from tip of nose to directly above base of tail b Bear lying on side, from base of tail to tip c Over curves, bear lying on side, from superior margin of scapula to elbow to proximal margin of plantar pad

Based purely on body mass data, the Sri Lankan subspecies is smaller on average than sloth bears on the Indian mainland. To date, there is insufficient information to know if the differences in body mass and coat characteristics reflect a cline where the bears get increasingly larger and hairier towards the northern end of the distribution range.

Sri Lanka: Geography, Society, and Economy Sri Lanka’s climate is tropical and marked by two monsoonal periods bringing rainfall, the majority of which is received by the southwest region of the island. Sri Lanka has three main ecological regions based on total annual rainfall: the wettest region is in the southwest and receives over 2,500 millimetres of rainfall annually, the dry zone receives less than 1,900 millimetres of rainfall, and a zone of intermediate precipitation separates the wet and dry zones (Domrös, 1974). The majority of people live in the wet zone where land use is dominated by agriculture.

The island’s capital city, Colombo, is located along the west coast.

The island consists of three main physiographic regions: the coastal lowlands (0–250 metres) cover the majority of the land area and

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1 Natural History of the Sloth Bear and Cultural Perspectives

Historic bear range

Dry zone Intermediate zone Wet zone

0–250 m

251–750 m

>750 m

N E

W 100 a) Precipitation zones

Climate and topographical maps of Sri Lanka.

There is no evidence that sloth bears ever occurred in the intermediate and wet zones of the country. (Modified from Ratnayeke et al., 2007b)

0

100 Kilometres b) Topography

S

surround two successively higher and greatly dissected plateaus occupying the central hill country of the island. Agriculture and settlements cover nearly 50% of the land area and dense forests approximately 24%–26% (Ratnayake et al., 2002; United Nations Environment Programme [UNEP], 2003). Much of the remaining land is lowland sparse forest (18%) comprising sparse, low-stature vegetation and grasslands (UNEP, 2003). Lowland sparse forests occur naturally due to local edaphic factors, or from disturbances such as logging, fire, and abandoned agriculture (G. A. D. Perera, 2001).

Sri Lanka’s human population density, 82% of which is rural, is currently estimated at 342 people per square kilometre (Department of Census and Statistics, 2018). In the early 2000s, although human life expectancy (73 years) and literacy (91.6%) were high, between 20% and 25% of the population were below the national poverty level (World Bank, 2002). Agriculture has been the mainstay of Sri Lanka’s economy, accounting for more than 40% of total employment (World

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Sloth Bear: The Barefoot Bear of Sri Lanka

Bank, 1995). Many rural livelihoods are sustained through small-scale or subsistence agriculture and many families are compelled to exploit forests for fuel, food, and other sources of income such as bushmeat and honey.

Almost 30 years of civil war saw the loss of nearly 70,000 lives and the displacement of over half a million people, causing acute humanitarian crises in the Northern and Eastern Provinces of the country (Bajoria, 2009). This region of civil conflict also constitutes the largest tracts of sloth bear habitat on the island. Since 2002, economic welfare in Sri Lanka has improved, except for pockets of extreme poverty that persist in areas including regions recovering from the civil conflict (Newhouse et al., 2016). In these areas, subsistence 12

Map of Sri Lanka’s cities, towns, and primary roads (Image by Central Intelligence Agency/ CC0 1.0)

1 Natural History of the Sloth Bear and Cultural Perspectives

living that is well below the poverty level forces most rural families to use the forests to meet immediate needs, increasing the potential for human-bear conflicts. Balancing the needs of humans and sustaining a wilderness for bears and other species of wildlife present enormous socioeconomic and conservation challenges.

Sloth Bears and Humans Villagers consider the sloth bear a dangerous adversary and it is one of the most feared animals in the jungles of Sri Lanka for its unpredictable nature and ferocious temper (Phillips, 1984). The native aboriginal people of Sri Lanka, the Veddas, are the only human groups to have traditionally lived alongside bears and have been forced to engage in direct man-to-bear combat with serious, if not mortal, consequences to both (Spittel, 1924, 1942).

The aboriginal people of Sri Lanka reviled sloth bears. Some Vedda groups referred to the bears as keria, or the worst form of vermin in the forest (Seligman et al., 1911/2008). The axe, typically carried over the shoulder, was the Vedda’s tool of choice to kill or drive off an attacking bear.

Elephants and buffaloes can be driven off by a thunderflash and leopards will slink away when they detect human presence, but an angry sloth bear is the only animal that cannot be stopped with shotgun fire, or so hunters have claimed. This is a remarkable paradox, for the sloth bear is also known to be a shy animal that feeds on things

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Sloth Bear: The Barefoot Bear of Sri Lanka

as innocuous as termites and fruit, avoiding areas used by humans as much as possible or confining its movements to times when humans are asleep.

In national parks where the threat of conflict with humans is reduced, sloth bears might be seen in the early mornings and late evenings.

Yet, they remain a rare sight for visitors who delight in the comical appearance and clownish gait of a sloth bear on the move. A sloth bear, ambling around in search of food, gives little indication of its speed, strength, and fury when provoked.

The International Union for the Conservation of Nature (IUCN) lists sloth bears as “Vulnerable” on the grounds of the loss and degradation of bear habitat resulting from the demands of human population growth (Dharaiya et al., 2016). In Sri Lanka, sloth bear habitats both within and outside of protected areas are under the unrelenting pressure of clearance for rural settlement, swidden agriculture, and resource extraction, which may play a role in the increasing frequency of human-sloth bear conflicts (Ratnayeke et al., 2014).

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Even in national parks, seeing a sloth bear is a rare and exciting event. Visitors watch, transfixed, as a sloth bear calmly paces down a road in Yala National Park, Sri Lanka.

1 Natural History of the Sloth Bear and Cultural Perspectives

Until sloth bears were placed under legal protection, efforts to wilfully exterminate the bear were responsible for its extirpation in many districts in India in the early 1900s (Pocock, 1941). In Sri Lanka, similar perceptions that bears were vermin and a threat to human safety made indiscriminate killing of sloth bears acceptable (Santiapillai & Santiapillai, 1990). Poaching networks in India that target sloth bears for lucrative body parts such as paws and gall bladders have also been recently reported (Dharaiya et al., 2016). In recent decades, the advancing tide of forest clearance and human settlement has been the principal reason for the decline and extirpation of sloth bears.

The chapters that follow describe my experiences, including those of the small team that worked with me, during a three-year study of sloth bears in Sri Lanka. I describe what we learnt about the ecology and behaviour of these bears, and the special challenges they face in a country with remarkable biological diversity but also with multiple pressures exerted by a growing rural human population.

The next chapter addresses characteristics of a typical sloth bear habitat and the first systematic effort in 2004 to map the distribution of the bear in the island on a landscape scale. This work resulted in a landscape model, which we used to predict where probable recent losses to sloth bear range had occurred. I present opinions and views of bear conservation from interviews and discussions with people that used forests occupied by sloth bears.

In the third and fourth chapters, I discuss what is known about the ecology of the bear, including the new information we collected from the first radio telemetry study and remote camera survey of this species in Sri Lanka. During the survey to map the distribution of the bear, rural people directed us to where several survivors of sloth bear attacks lived. Their compelling experiences led to a study on the circumstances and characteristics of sloth bear attacks on people, which I discuss in the fifth chapter.

In the final chapter, I reflect on the conservation of this fascinating yet controversial species, the main threats to its persistence, and the conditions that will best improve its chances of survival in the dryzone forests for future generations.

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