GEORGE M. McKA Behavior and Ecology 0

the Asiatic Elephant

in Southeastern Ceylon A

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY NUMBER 125
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SMITHSONIAN CONTRIBUTIONS TO

ZOOLOGY

NUMBER 125

George M. McKay Behavior and Ecology of

the Asiatic Elephant

in Southeastern Ceylon

SMITHSONIAN INSTITUTION PRESS

CITY OF WASHINGTON

1973
ABSTRACT

McKay, George M. Behavior and Ecology of the Asiatic Elephant in Southeastern Ceylon. Smithsonian Contributions to Zoology, number 125, 113 pages,

63 figures, 22 tables, 1973.—This paper reports on a three-year study of the behavior and ecology of the Asiatic elephant (Elephas maximus maximus L.) in

the Gal Oya and Ruhunu National Park areas of Ceylon. The study area in

eastern Ceylon is in a zone which shows a gradation in climate from moist to

arid. This gradient is correlated with gradients in the distribution of plant

species and of vegetation types.

Two populations were studied in detail. The first, in the area around the

Gal Oya National Park, contained an estimated 260—300 elephants. A second

population, in the area around Lahugala Tank, was estimated to contain about

150 individuals. An analysis of population structure is reported and the behavior patterns involved in locomotion, resting, feeding, drinking and bathing,

rubbing, elimination, and thermoregulatory flapping of the ears are described.

Movement rates while feeding were measured and mechanisms of visual communication are described, including two threat displays, nine vocalizations, and

several nonvocal means of auditory communication.

Composition and structure of herd organization, seasonal movements, and

variation in home ranges are discussed. Movement patterns of solitary adult

and subadult males in relation to food availability and dominance roles are

also considered.

Elephants make use of the full variety of vegetation types available to them.

Food plants of 88 species were identified, the majority being trees and shrubs.

Several important food plants were analyzed for caloric density, and chemical

analyses of 8 species showed higher percentages of protein for shrubs as opposed

to grasses.

Recommendations for management of the elephant within the park and the

establishment of a buffer zone between the park and areas of intensive cultivation are made.

Official publication date is handstamped in a limited number of initial copies and is recorded

in the Institution's annual report, Smithsonian Year.

Library of Congress Cataloging in Publication Data

McKay, George M., 1944

Behavior and ecology of the Asiatic elephant in southeastern Ceylon.

(Smithsonian contributions to zoology, no. 125)

Bibliography: p.

I. Indian elephant —Behavior. I. Title. II. Series: Smithsonian Institution. Smithsonian contributions to zoology, no. 125.

QL1.S54 no. 125 [QL737.P98] 591'.08s [599'.61] 72-8961

For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington. D.C. 20402

Pric e Sl.7"> domesti c postpaid , or SI.5 0 GI' O Bookstor e
Contents

Page

Introduction 1

Acknowledgments 2

Taxonomy 3

Anatomy and Physiology 3

Behavior and Social Organization 3

Ecology 4

Ceylon's Elephants-Game, Pest or Heritage? 5

Methods and Materials . 5

Field Observations 6

Sex and Age Criteria g

Laboratory Studies \\

The Study Area 1 j

Geology and Topography \\

Drainage Systems 12

Climate and Weather 13

Climate . 13

Weather 15

Soils 15

Vegetation 17

Types and Distribution . 17

Phenology 24

Fire 25

History of Development 26

Agriculture 26

Deforestation and Afforestation 30

The Vertebrate Fauna 31

The Invertebrate Fauna 33

Populations 33

Distribution of Populations 34

Population Structure 37

Natality 40

Mortality 42

Behavior Patterns 43

Locomotion . 43

Resting and Sleeping . . 44

Feeding 45

Grasses 45

Shrubs 45

Drinking and Bathing 46

Mud-and-Dust Bathing and Rubbing 48

Defecation and Urination . 49

Exploratory Behavior 50

Flapping of the Ears 50

iii
Page

Short-term Activity Patterns 53

The Daily Activity Cycle 53

Times of Activity 53

Patterns of Activity . 55

Feeding Patterns . 56

Time and Energy Budget . 58

Social Behavior 62

Initial Encounter 62

Patterns of Interaction 62

Interactions with Little or No Contact 62

Interactions with Extended Contact 63

Interactions between Males and Females 65

Communication . 65

Tactile and Chemical 65

Visual Communication 65

Auditory Communication 67

Maternal and Infant Patterns . 69

Organization of Elephant Groups in Time and Space 70

Group Sizes 70

Composition of Groups Containing Females 72

Medium-term Organization of Groups 75

Long-term Organization of the Herd 76

The Role of the Male 81

Movement Patterns and Habitat Utilization . 85

The Home Range 85

Water . 85

Trails 87

"Rest Rooms" .. . 87

Rubbing Trees 88

Seasonality of Movements 88

Use of Habitat Types . . 90

Food Plants 92

Feeding Behavior 94

Density and Biomass 96

Effects on the Habitat 99

Water Holes and Trails 99

Effects Associated with Feeding . 99

Elephant and Man 101

The Current Problems ..... . 101

Agriculture and Movements 101

Crop Raiding 102

Competition from Domestic Stock 103

The Outlook . 103

Recommendations 104

Literature Cited 105

Appendix 1: Gazetteer of Place Names Used in Text . 111

Appendix 2: Data on Flapping of Ears 112
George M. McKay Behavior and Ecology of

the Asiatic Elephant

in Southeastern Ceylon

The creation of elephants was holy, and for the profit of sacrifice to the gods, and especially

for the welfare of kings. Therefore it is clear that elephants must be zealously tended.

The egg from which the creation of the sun took place—the Unborn took solemnly in his

two hands the two gleaming half shells of that egg, exhibited by the Brahmanical sages, and

chanted seven samans at once. Thereupon the elephant Airavata was born and seven other

noble elephants were severally born, through the chanting.

Thus eight elephants were born from the eggshell held in his right hand. And from that

in his left hand in turn eight cows were born, their consorts. And in the course of time those

elephants, their sons and grandsons, [etc.], endowed with spirit and might, ranged at will over

the forests, rivers and mountains of the whole world.

And the noble elephants went to the battle of the gods and demons, as vehicles of the lords

of the quarters, Indra, Agni and the rest. Then in fright they ran away to Virinca [Brahma].

Knowing this, the spirit of Musth was then created by Fate; when it had been implanted in

them, infuriated they annihilated the host of the demons, and went with Indra and the rest

each to his separate quarter.

NlLAKANTHA*

Introduction

Wherever elephants and men have coexisted, interaction has been inevitable. The cave paintings

of Europe and North Africa amply demonstrate the

importance of proboscideans as prey for preagricultural man (Carrington, 1958). The rock paintings in southern Africa are all that remain to

indicate that elephants were hunted by the bushman, but elephant hunting traditions still survive

among a few African tribes (Sikes, 1971).

To agricultural man the elephant assumed new

significance. He became a beast of burden, an instrument of war, an object of reverence, an agriGeorge M. McKay, Research Associate, National Zoological

Park, Smithsonian Institution, Washington, D.C. 20560.

Present address: Taronga Zoological Park, Mosman, New

South Wales, 2088, Australia.

• From Matanga-Lila. In Edgerton, The Elephant Lore of

the Hindus: The Elephant-Sport of Nilakantha. New Haven:

Yale United Press, 1931.

cultural pest, a status symbol, and a resource to be

exploited for the beauty of ivory. Until European

settlers began invading the African continent in

the last two centuries there was little contact between agricultural man and elephant on that continent. The Carthaginians undoubtedly used and

trained native African elephants for warfare (Sikes,

1971) and the Kushites of Meroe may also have

used indigenous elephants, Shinnie's (1965) argument to the contrary is not convincing, being based

on the supposed intractability of this species.

It is in Asia that elephants and humans have

been in prolonged and intensive contact, and it is

there that the significance of the elephant to man

has become the most complex.

The earliest date at which elephants were tamed

in India is not known, but it is certain that elephants were in well-established use before the invasion of the Greeks. Elephants appear on plaques

dating from the Indo-Sumerian period (5000-1000

B.C.) in the Sind Valley (Coomaraswamy, 1917).

1
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

From the time of the Aryan invasions and the advent of Sanskrit writing there have been numerous

written references to elephants including the Matnnga-Lila by Nilakantha. Stracey (1963) gives a

brief summary of the history of elephant domestication in India, and Armandi (1843) reviews the

use of the elephant in war. In India elephants

were captured from the wild using a number of

different methods. All are described in detail by

Stracey (1963) including the khedda or stockade

method popularized by G. P. Sanderson of the

Mysore Civil Service (whose own account of the

method appears in Sanderson, 1878). During the

period of British occupancy of India, the capturing

and training of elephants passed from the hands

of private individuals to the government departments. Several books, written by civil servants

concerned in khedda or logging operations, appeared, which combine, often in a charming manner, ancient elephant lore with modern veterinary

medicine. Foremost among these are Steel (1885),

Evans (1910), and Milroy (1922).

ACKNOWLEDGMENTS

Financial support for this study was obtained from

the following sources: Smithsonian Institution Foreign Currency Program (Grants Nos. SFC—7—0059

and SFC-8-7428 to Drs. J. F. Eisenberg and H. K.

Buechner), the World Wildlife Fund (Grant No.

258 to Drs. Buechner and Eisenberg), the Fauna

Preservation Society (donation of two Land Rovers), and the University of Maryland Graduate

Research Fund. Logistic support was provided by

the U. S. National Zoological Park, Smithsonian

Institution, and by the staff of the U. S. Embassy,

Colombo.

I cannot properly thank my friend and advisor,

John F. Eisenberg, who, from the time when this

study was merely a casual thought through to completion, gave unstintingly of his time and energy.

My thanks to the entire staff of the Department

of Wild Life, under the direction of Mr. W. L. E.

deAlwis, who provided the cheerful cooperation

without which none of this work would have been

possible. To single out any individual in the department for special praise would be to slight the

others—all were equally helpful in their official

capacities and willing, as individuals, to discuss

their experiences with elephants.

Professor H. Crusz, Department of Zoology,

University of Ceylon, Peradeniya, provided not

only office space and technical assistance but a

warm, friendly atmosphere which was gratefully

appreciated.

Professor F. S. C. P. Kalpage\ Professor P. Seneviratne, Dr. M. R. Jainudeen and Dr. J. B. Jayasinghe of the Faculty of Agriculture and Veterinary

Medicine, University of Ceylon, Peradeniya, provided laboratory facilities, technical assistance and

stimulating discussion.

Assistance in tedious laboratory analyses was provided by Malini Pereira, without whose help my

time in the field would have been even less.

Assistance and companionship in the field work

itself were provided by far more people than can

possibly be acknowledged here. Foremost among

the many are Melvyn C. Lockhart, who in 1967

taught me from his own experience most of what

I was later to extract from my notebooks; E. F.

Desmond Lockhart, who helped in more ways than

can be remembered and whose companionship in

the last two years was invaluable; Bevis Ekanayake

whose only fault was that he never tired; Childers

[ayawardene and Ranjit G. Cooray, two people

who have not forgotten the importance of a sense

of humor; Peter L. Comanor, Dieter Mueller-Dombois and a host of other botanists; Emis Appuhamy,

whose singing livened many a dull evening in

camp; Gomis Appuhamy, who never failed to find

the path home; Piyadasa, who patiently endured

some of the silliest things he had ever seen a European doing; Anil Jayasuriya and A. P. W. Nettasinghe who many times shared with me the joy

of a good day's observation and the disappointment

of a day's fruitless hiking; Anthony Solomonsz, who

learned to despise the water buffalo; B. Somapala

and Richard, neither of whom could I convince to

make any curry hot enough; Viswakularatne, whose

alert eyes and ears saved my life more than once;

and lastly, but by no means least, an anonymous

bus driver whose sense of responsibility was hampered only by a snake.

As though companionship and help in the field

were not enough, many people must be thanked

for their friendship which made the Ceylon years

pleasant ones and for their willingness as colleagues to discuss ideas both exciting and insane.

Sanity being a relative state, I would like to thank
NUMBER 125

the following especially, for their help in keeping

me a peg or two above the borderline: "Uncle

Joe" Peries, who made life at Inginiyagala an experience never to be forgotten or regretted—the

perfect host and friend; Bradman and Dami Weerakoon, Mr. and Mrs. Osman de Silva; Doreen Lockhart and Denise Lockhart who gave as freely of

their hospitality as they did of their husbands; R.

Rudran, Tissa Herath and all of the honors students from the University of Ceylon; Theodore

Grand, Wolfgang Dittus, Robert W. Read, and a

whole host of others. Special thanks go to Gilbert

Manley whose willingness to share both working

time and leisure time was endless. His interest in

and enthusiasm for life were as valuable to me as

our many long discussions on more technical subjects. The highest compliment I can ever pay him

was that he alone could appreciate with me the

finding of a rare book and a Rattus ohiensis.

Not all of the work was conducted in the field.

Both in preparatory work and in writing, I am

indebted to my many friends at the University of

Maryland and at the U.S. Zoological Park both for

their companionship and their willingness to discuss matters biological. I would particularly like

to thank Joseph and Phyllis Marshall, Robert and

Phyllis Phillips, Christen Wemmer, Douglass and

Elsie Morse, Robert Jaeger, Larry Collins, Herbert

(Sonny) Stroman, Leo Slaughter, Judith Block, and

Warren Iliff. Peter Mundel deserves especial mention for his help in preparing several of the figures.

H. K. Buechner, J. Potter, V. Flyger and J. Haley

read the entire manuscript and offered much valuable criticism.

I owe two people a debt which I can never

adequately repay. Nancy Muckenhirn has given,

in all phases of the study, much more freely of her

time and energy than she could afford. Wyotta

Holden, with her energy, interest, and affection

made a wistful dream become reality.

TAXONOMY

Ellerman and Morrison-Scott (1951) list two subspecies of Elephas maximus from Ceylon, equating

E. m. maximus Linnaeus with E. m. vilaliya Deraniyagala (sensu Deraniyagala) and accepting E.

m. ceylanicus Blainville as the elephant inhabiting

most of the island. McKay (n.d.) proposes that

E. m. xrilaliya represents no more than a few extremely large individuals in a highly variable population and considers that it should be placed in

synonymy with E. m. maximus. For the purposes

of this paper I will consider that the island of Ceylon is inhabited by one subspecies.

ANATOMY AND PHYSIOLOGY

Frade (1955) presents a comprehensive summary

of the literature concerning the anatomy of both

living species of elephant. The only point on

which further discussion is necessary concerns the

structure of the stomach. Tennent (1867) discussed

the work of earlier anatomists concerning the enlarged and folded cardiac portion of the stomach.

He likened the folds to the so-called water cells

in the stomach of the camel, and concluded that

they must serve for storage of water. Sikes (1971)

treats this problem (in Loxodonta where the structure is identical) only slightly. One potential function for the folded cardiac region might be to

allow greater expansion than if it were not so corrugated. I have frequently observed elephants,

feeding in lush grassy areas such as Lahugala Tank

(p. 58), to look quite slender as they begin feeding;

but after as few as five to six hours of intensive

feeding, these same individuals have extremely

bulging bellies. It would appear reasonable that

if the rate at which an elephant can ingest food

greatly exceeds the rate at which the intestines and

caecum can process it, there would be a distinct

advantage to the possession of a very elastic stomach. In the absence of more detailed anatomical

data, one can do no more than speculate; it is a

possibility worthy of further investigation.

Benedict (1936) conducted a series of experiments to examine several aspects of the physiology

of elephants, using particularly one adult female

Elephas. Details of his findings relevant to this

work will be discussed in the appropriate places

in the text. More recently, Sikes (1971) has summarized the available data on physiology of Loxodonta and provides interesting comparisons with

the data of Benedict.

BEHAVIOR AND SOCIAL ORGANIZATION

Many accounts of elephants have been written by

persons connected with forestry in India or by

civil servants and planters who indulged in "sport"
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

during their leave. Books, such as Baker's (1855),

are more concerned with the "sport" of shooting

elephants than with the lives of the quarry. Such

accounts as Williams (1950) and Stracey (1963), on

the other hand, give not only a vivid account of

the intricacies of logging and elephant-capturing

operations but provide, in addition, many insights

into the behavior of the elephants. In particular

Williams' (1950) descriptions of the social behavior

of elephants, especially with regard to sexual behavior, parturition, and the participation of females in the care of the young, reflect careful

observation and interpretation. Sanderson (1878)

gives several precise descriptions of their behavior

including five vocalizations (with implied meanings) and one threat display. His observations

(1878:49) on the composition of herds deserve attention:

Herds of elephants usually consist of from thirty to fifty

individuals, but much larger numbers, even one hundred,

are by no means uncommon. When large herds are in localities where fodder is not very plentiful, they divide into

parties of from ten to twenty; these remain separate, though

within two or three miles of each other. But they all take

part in any common movement, such as a march into another

tract of forest. . . . Each herd of elephants is a family in

which the animals are nearly allied to each other.

Tennent (1867:45) also discusses the composition of herds:

A herd of elephants is a family, not a group whom acddent

or attachment may have induced to associate together.

Similarity of features and caste attest that, among the

various individuals which compose it, there is a common

lineage and relationship. In a herd of twenty-one elephants,

captured in 1844, the trunks of each individual presented the

same peculiar formation,—long, and almost one uniform

breadth throughout, instead of tapering gradually from the

root to the nostril.

He also refers to a low number of males with

herds, although he does not go so far in interpreting this as Sanderson (1878:49), who states that

the herd is "invariably led by a female, never a

male."

More recent reports on behavior of Elephas are

few. Elapata (1969) observed in 1957 a series of

copulations involving two adult females in which

one of the females mated with two different bulls

and one of these bulls mated with the second

female. The sequence of behavior observed is very

similar to observations of my own (Eisenberg, McKay, and Jainudeen, 1971). Deraniyagala (1958)

reported an interaction between two adult males

(observed by S. A. I. Elapata, A. H. E. Molamure,

and V. Atukorale) which he termed "pseudo-combat." From his description this appears to have

been a sequence similar to what I have described

as "play-fighting" (p. 65).

ECOLOGY

While there are many accounts which describe the

behavior of elephants, there are relatively few data

on the ecology and status of populations. Sanderson (1878) mentions that females give birth every

2y2 years and says that the majority of calves are

dropped in Mysore between September and November (toward the end of the rainy season). Williams (1950:39), however, states that in Burma most

wild elephant calves are born between March and

May which in that area is the onset of the rainy

season.

Williams (1950) also estimates that in Burma

approximately 25 percent of calves fall prey to

tigers—the only estimate of the extent of predation on elephants I have been able to find.

Reliable estimates of populations of elephants

are few. Stracey (1963:211) reports that his department removed some 900 animals from the Naga

and Mikir hills in northeastern India, an operation which "almost cleaned out the elephants

there." He also estimates the population for Uttar Pradesh in 1965 at 600—an increase of 350 over

his estimate for 1955. Singh (1969), however, on

the basis of a number of detailed surveys considers

that the population for that state as of 1967 "is not

likely to be more than 400 in number."

Data from Burma are poor: Stracey (1963) estimated 10,000 for 1955 but Williams (1950) estimated 6,000. The situation in west Malaysia is

somewhat better known. Medway (1965) estimated

a total population of 692 in 1964-1965. This number is low enough in itself, but inspection of his

figure 2 shows that there are only two herds with

more than 20 individuals and ten herds with 10—20

individuals. Not only are the herds small but they

are widely dispersed. Stevens (1968) estimated that

the 1968 population in Malaysia was 486—he maintained that Medway's (1965) estimate was too op

timistic.
NUMBER 125

CEYLON'S ELEPHANTS—GAME, PEST OR HERITAGE?

Elephants have been in use by man in Ceylon for

at least the past 2000 years. According to Gooneratne (1967) a detachment of elephants was a traditional part of the army of all of the ancient

Sinhalese Kings. According to Deraniyagala (1955:

45) King Raja Sinha I was able to muster 2200

elephants for his attack on the Portuguese fort at

Colombo in 1588. After the spread in use of cannon, the elephant apparently became less useful in

battle, but Schweitzer (1682) describes the process

of conditioning elephants to the sound of gunfire.

Elephants have also been traditionally associated

with such ceremonial functions as religious processions. Herport (1669) refers to the King of Kandy

as maintaining a stable of 100 elephants for ceremonial purposes. Knox (1681) ascribes other functions to these animals—executioners and combatants

in fights, of which the King and his court were

regular spectators.

Three methods for capturing elephants were in

use before the Portuguese era—pitfalls, noosing, and

decoying. The pitfall technique, described by Tennent (1867) and Stracey (1963) simply required the

digging of a deep pit along a pathway and covering

the hole in order to delude the elephant. The

noosing technique which required much more skill

and bravery is described by Tennent (1867). In

this method the noosers approach the elephant on

foot and slip a rope around one leg of the animal

tying it immediately to a tree. This method was

practiced extensively by men of Arabic descent who

live in the east of Ceylon, and the tradition is not

quite dead. The third method, described by Knox

(1681) involved noosing also but the approach was

made by men mounted on trained elephants. This

technique (known in India as mela-shikar) is described in detail by Stracey (1963).

The Portuguese apparently introduced the

method of capturing elephants by means of a corral

(KraaJ-Ceylon; khedda-lndia) (Tennent, 1867). By

using this method large numbers of animals could

be obtained in a short period of time.

According to Abeyasinghe (1966) the Portuguese

maintained an annual demand of 37 elephants for

export from two kraals. These produced an average revenue of 9250 Rixdollars (roughly 15 percent of the total revenue to the state). According

to de Silva (1969) 1875 elephants were exported

from 1863-1884, producing a revenue of Rs. 144,-

715. Thus even in the colonial era, the elephant

was an important part of the economy as an export

commodity.

But the value of the elephant was not only economic. Elephants were and still are used as

draught animals—particularly in logging operations. In 1969 there were 532 tame working elephants on Ceylon (Jayasinghe and Jainudeen,

1970). Elephants still participate in ceremonial

processions such as the annual Esala Perahera at

Kandy, according to the ancient tradition that tenants of temple lands or lands granted by the king

must participate in the Perahera (Coomaraswamy,

1956). Thus the elephant is still a viable part of

the cultural heritage of Ceylon.

It is interesting to note that Knox (1681), Heydt

(1744), and Abeyasinghe (1966) (who was writing

about the Portuguese era) mention elephant catchers and trainers as a distinct caste, while Coomaraswamy (1956) in his list of castes does not.

The elephant can also be an agricultural pest.

Knox (1681) has noted that "these Elephants do,

and may do, great dammage to the Country, by

eating up their Corn, and trampling it with their

broad feet, and throwing down their Coker-nut

trees, and often times their Houses too." Similar

statements are made by Herport (1669), Schweitzer

(1682), and Heydt (1744), who are discussing the

areas around Kandy, Colombo, and Ratnapura—

districts from which the elephant is now long gone,

but where they were, at that time, abundant.

As colonial powers the Portuguese and Dutch

made relatively little impression on the ecology of

Ceylon. But the advent of the British brought two

new limiting factors into play against the elephant

—the coffee bush and the rifle, often with both in

the hands of a single man. The story of the results

of this has been told many times: by proponents,

"sportsmen" such as Baker (1855), by contemporary

opponents (Tennent, 1867), and by modern writers

(de Silva, 1969). There are no records which allow

one to estimate accurately the total elephant population before the 19th century onslaught. If the

entire island were populated by elephants at the

present-day average of one elephant per two square

miles (p. 96), there could have been as many as

12,000. That there was an onslaught is well documented, however, as reported by Tennent (1867:

78), Marshall (1846), de Silva (1969), and others.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

The result of shooting and land clearing was

that by 1951 the total elephant population of Ceylon was estimated at approximately 1500 (Norris,

1959). For the past two decades there has been

an awareness in Ceylon that measures must be

taken in order to insure that some elephants will

remain. Norris (1959) made the first attempt to

survey the situation at that time, but concluded

that more information was needed. It was because

of this need for information and because of the

awareness of such a need by all of the people with

whom we worked in Ceylon that this study was

possible.

Norris (1959) posed three questions: "(1) How

many elephants do we want to keep? (2) How much

country do they need, remembering their seasonal

movements? (3) What land is available for them?"

The following report is an attempt to supply

the answers to questions 2 and 3 for a portion of

the island.

Methods and Materials

FIELD OBSERVATIONS

In the course of this study, 453 days were spent in

the field over a period of 2y4 years from February

1967 to October 1969. Of these days spent in the

field, 318 were in the major study area; 89 were in

Blocks I and II of Ruhunu National Park and 46

were spent in other areas outside of these two.

Work in Ruhunu National Park was concentrated

between April and October 1967 and work in the

Gal Oya—Lahugala area was conducted from February to July 1967 and from October 1967 until

October 1969.

In Ruhunu National Park the observer was restricted to working from a vehicle. As a result,

observations of elephants could only be made in

those areas where the animals were visible from

the roadway. Travel within the National Park was

restricted to daylight hours (0600 to 1800 hours),

and at all times the observer was accompanied by

a tracker, an employee of the Department of Wild

Life. As this park contained an extensive network

of sandy roads, the normal daily routine began with

a systematic survey of the roads within the park to

determine the movements of animals over the previous night. The author and tracker began this survey at dawn, following the same route (about 65

km) every day.

Whenever tracks of elephants were encountered,

the number of animals, approximate size, and direction of movement were noted on a map along

with the location of the footprints. Fresh deposits

of feces were also recorded as to location and number. Any signs of feeding by elephants (e.g., scarification, broken twigs, broken branches) were

recorded as to location and species of plants fed

upon. For those species of plants which could not

be identified in the field, specimens were taken

for later identification. By conducting this regular

survey in the early hours of each morning, it was

possible to obtain a sufficient amount of data on

the movements and approximate locations of elephants within the park. During this period, the

park roads were heavily used throughout the day

by both visitors and park staff. As a result, any

tracks laid down by elephants over night were usually obliterated within the first few hours of the

morning. On an average day, the entire circuit

took approximately two hours to complete and an

attempt was always made to complete the circuit

as quickly as possible. Whenever solitary males

were encountered during this early morning circuit,

their location was noted along with ongoing activity. After the circuit was completed, an attempt

was made later in the day to relocate the animal

that had been observed in the morning. No

herds were encountered during these early morning

surveys.

Following the completion of the morning circuit,

the rest of the clay was spent tracing animals in

those areas where tracks had been sighted the previous night. Whenever solitary males were encountered, they were observed for one hour or until

they moved out of sight, whichever occurred first.

Whenever herds were encountered, they were observed until they disappeared from sight or until

darkness made further observation impossible. If

no contacts with elephants were made by midafternoon, a second circuit of the park was made. Locations of all animals sighted were marked on

maps and individual characteristics of identifiable

animals were recorded upon each sighting in order

to provide a confirmation of identity. Animals observed in groups were classified according to comparative size classes. Observations were made with
NUMBER 125

the aid of a pair of 7-power binoculars, and records

were kept primarily in a field note book, although

a small portable tape recorder was used for some

observations. Whenever possible a photograph was

taken of each animal observed.

At all times during these observations in Ruhunu National Park, care was taken to observe the

animals from the greatest distance possible (usually

around 100 m) in order to minimize any potential

effect on the animals' actions by the presence of

the observers' vehicle. No attempt was made to

condition animals to the close approach of the vehicle, even though many of the animals in this

area appeared to be conditioned to the presence of

vehicles at a distance of 50 m.

The area in and around the Gal Oya National

Park is not covered with a network of roads as is

Ruhunu National Park and the location and observation of elephants in this area presented different problems from those of the Ruhunu area. In

the areas outside the National Park, it was possible

to travel by vehicle to places where the probability

of encountering elephants was high. In some instances it was possible to observe elephants from

the vehicle, as for example around the Amparai

airport, but in most cases it was necessary to continue searching on foot. In 1968 the staff of the

Department of Wild Life at Inginiyagala constructed a road extending from the outskirts of the

town into the southeastern portion of the National

Park. This allowed easier access to this area by

eliminating the amount of time spent in walking

to and from areas of observation. In the area immediately surrounding the Senanayake Samudra it

was possible to travel from point to point by boat.

From October 1967 to April 1968, a motorized

launch rented from the River Valleys Development

Board was used whenever available. When this

boat was not available outrigger canoes were rented

from local fishermen. From May 1968 until the

end of the study, a 14-foot fiber glass boat equipped

with an outboard motor was used.

Whether within the National Park or in the surrounding districts, the majority of observations

were made on foot. When traveling on foot the

observer was always accompanied by at least one

other person, as a safety precaution; firearms were

never carried. In working on foot within the National Park, the observer and assistant were accompanied at all times by a member of the Department

of Wild Life staff for the area.

As the town of Inginiyagala lies in a central position within the area studied, headquarters were

established at the rest house operated by the River

Valleys Development Board. Using this central location as a base, it was possible to work conveniently in the eastern half of the National Park and

in the surrounding areas to the east and south of

the park. Whenever observations were being made

in the western sector of the park, however, temporary camps were established at convenient points

on the bank of the Senanayake Samudra or along

the Gal Oya. As this study area is much larger and

more difficult to traverse than Ruhunu National

Park, no routine daily circuit was made; instead,

regular surveys were made either entirely on foot

or by driving or using the boat, as well as on foot.

Attempts were made to cover as much of the study

area as possible every week; but whenever a herd

was located, its movements were followed for as

many consecutive days as possible. Apart from our

own surveys, reliable reports of sightings by villagers and by Wild Life Department staff were used

extensively in helping to locate groups of animals.

When traveling on foot the observer and companions traveled in single file and an attempt was

made to minimize disturbance by enforcing silence;

although with some villagers who acted as guides,

silence was often impossible. Whenever elephants

were encountered, strict silence was enforced and

every attempt was made to remain downwind. Elephants encountered on foot were never approached

closer than was absolutely necessary to insure adequate observation, so that movements of the observer and mechanical noises, such as clicking by

cameras, would be less likely to disturb the animals.

Throughout the study no attempt was ever made

to habituate elephants to the preserfce of the observer. By strictly adhering to these procedures, it

was possible to obtain a large amount of data from

animals that one can reasonably assume were unaware of the presence of an observer and therefore

unaffected by his presence. Over the entire Gal

Oya area elephants and man are in frequent contact and the elephants generally resorted to flight

when they became aware of the presence of the observer. The patterns of responses of elephants to
8

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

man are described by McKay and Muckenhirn (in

prep.).

Besides observations in Gal Oya National Park,

periodic visits to Lahugala Tank and the coastal

strip extending south from Lahugala to the Kumbukkan Oya were made in March, July, November,

and December of 1967; February, May, July, and November of 1968; and March, June, August, and

October of 1969. For the most part these visits

consisted of a minimum of one trip from Lahugala

to the Kumbukkan Oya in order to determine the

presence or absence of elephants along this route

and one to several days intensive study of the

usage of Lahugala Tank and neighboring tanks by

herds of elephants. At Lahugala observations were

made either from the banks of the tank itself or

from a tree house, constructed in July 1967, on the

eastern side of the tank. Observations were also

made from a similar tree house constructed at the

neighboring Kitulana Tank. At Lahugala it was

possible, to have a view of the entire tank and, by

using a telescope with 20, 25, and 50 power lenses,

to follow the activity patterns of elephants throughout the daytime hours. On two visits the author,

assisted by Mr. Desmond Lockhart and Mr. Anil G.

Jayasuriya, was able by alternating shifts to follow

the usage of the tank by elephants over several

24-hour cycles.

Whenever elephants were encountered the first

data to be recorded were the time, location,

and physical description, plus the number in

the group. The description for each animal included sex, size class, and individually distinctive

characteristics. A great deal of variability exists

within the population as regards shape of ears,

shape and even presence of hairs on the tail, patterns of depigmentation around the trunk base,

face, ears, and shoulders, folding of the ears, and

the presence of tears or holes in the ears. Besides

these characteristics, many animals were also readily identifiable as individuals by the presence and

patterns of cysts on the skin. Examination of several dead animals demonstrated that many of these

cysts, which are visible as large bumps on the skin,

were actually encysted bullets and pellets from shotguns. At the beginning of a series of observations

on a herd, the group was counted a minimum of

three times or until a consistent count was obtained. Counts were repeated at intervals throughout the observation period. Such repeated counts

allowed a continuing check on the number of animals and revealed any shifts in grouping tendencies

or movements.

Observations of solitary animals or small groups

were recorded in a notebook; but for large herds

frequent use was made of a portable tape recorder

from which notes were later transcribed. A watch

with a sweep-second hand was used for measuring

intervals and durations of acts observed, although

for more accurate determination, of such patterns

as flapping of ears and feeding rates, a stop watch

was used. A brief description with at least one

photograph of every animal or group of animals

was made to confirm identifications of individuals.

In this way it was possible to accrue reliable descriptions for many of the animals and to minimize

the possibility of confusing those of similar appearance.

SEX AND AGE CRITERIA

The most reliable determinations of sex were those

where the genitalia were visible. The penis sheath

of the male and the vulva of the female can frequently be seen as the animal walks, particularly

if it is walking at an angle away from the observer.

Genitalia become more readily visible during urination and for very young animals this is the only

time at which sex can be realiably determined.

Reproductively active females can also be distinguished by tumescent mammae.

The sex of adults can also be determined from

the general conformation of the body. Adult males

usually have a massive trunk base which protrudes

as a bulge below and in front of the eyes and a

second swelling around the narial opening in the

skull, above the eyes. These, along with the enlarged parietals and occipitals, give the male its

distinctively large and bulky head. Females, however, have a narrower trunk base and generally

lack the prominent bulge above the eyes and the

swelling of the parietals. The head of the female

is thus more square and relatively more slender in

outline. Besides these differences in the shape of

the head, there is usually a sex difference in the

shape of the back. The female is generally more

box-shaped with a relatively straight back and vertical hindquarters, while the male tends to have a
NUMBER 125

more convex back, which curves more gradually

into the hindquarters.

The frequency of tusks among males on Ceylon

is generally low but varies from region to region.

In the Gal Oya area only one tusker was seen

among more than 35 adult males—and he was seen

only during November 1967. At Lahugala two

tuskers were known to be among the population of

twenty-five "resident" adult males and three subadult tuskers were seen on one occasion each. Many

elephants, both males and females, possess tushes

or incisors smaller than the typical tusk. These

tushes may be either circular or oval in cross-section

and sometimes protrude to 20 centimeters or

more beyond the lips. The oval type, which is

generally long (15-30 cm) and decurved, as opposed to the recurved tusk, was only seen in males,

but the circular type, which often is broken at the

gumline, was seen in both sexes. While tusks and

tushes were not always helpful in sex determination, the great variety in shapes did aid in recognizing individuals.

Reliable age estimates for animals observed in

the field present a problem, the solution of which

is unfortunately not yet in sight. Johnson and Buss

(1965), Laws (1966), Sikes (1967), and Krumrey and

Buss (1968) have devised techniques based on tooth

criteria which can be used to estimate the age of

Loxodonta, but these techniques require a dead

animal. Laws (1966) does give a tentative chart

for estimating ages based on shoulder height but

acknowledges the relative lack of reliability in this

method.

Considering the scarcity of known-age skull

material for Ceylonese elephants and the lack of

opportunity to examine large numbers of dead ones

in the field, two methods of age classification only

were open. The first method is to group the animals

observed into four classes based on developmental

stages and reproductive status as infants, juveniles,

subadults, and adults.

The criteria for an infant, other than size, that

could be used in the field included long hair on

head and back, short trunk (can touch ground but

unable to rest the hand of trunk on the ground),

frequent suckling, continuous proximity to an adult

and lack of association with juveniles for long

periods. Like Loxodonta (Laws, 1966), infant

Elephas can walk under their mothers. The distinction between juveniles and subadults is not so

easy. Juveniles tend to remain together and form

play-groups when a herd is feeding in one spot,

whereas subadults tend to remain with the adults.

Subadult males are frequently seen away from

herds. One character that is probably reliable with

the males is the size of the penis. At sexual maturity (and subadults are considered here to be

physiologically mature), the penis appears to become larger. This difference can only be determined

during urination. Subadult females often show

tumescence of the mammae.

Adult males can be distinguished by the enlargement of the head and the distinct penis sheath;

adult females by the square back. Subadults of

both sexes show the beginnings of differentiation

into these two types of body conformation.

Using these criteria alone it is possible to determine that subadult females are undoubtedly a

part of the reproductive population but subadult

males, while probably capable of breeding, do not

appear to be reproductively active.

The second method of estimating age, which was

used in parallel with the above determinations,

involved a comparison of the height of any individual with the height of a large adult female.

By a visual comparison it is thus possible to distinguish nine size classes, the fixed points of which

are: Class 1—an infant capable of walking under

the mother, and Class 8—a large adult female.

Classes 2 through 7 represent equal divisions between the two fixed points and Class 9 is any

animal larger than a large female (many adult

males). These nine classes can then be compared

with available data on shoulder height for knownage animals.

Data on heights of Asiatic elephants are summarized by Hundley (1934), Kurt and Nettasinghe

(1968), Reuther (1969), and Jainudeen and

Jayasinghe (pers. comra.). Based on those data it

is possible to construct the growth curves shown

in Figure 1. The lines on the graphs indicate the

approximate upper and lower limits. As can be

seen from these growth curves, there is an initial

period of rapid growth followed by a gradual

decline in the growth rate. Differences in growth

between the sexes appear at about 5 years. From

this point the decline in growth rate is greater for

females than for males. Females appear to reach
10 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

2 8 0

1/1

LLJ I/I

M <

ui - "

U

i

8

7

6

5

4

3

2

1

-

•

:

/

/ • .

i

/

i

JO

i

1

A

A A

*——

•

FEMALES

20 30 40 5 0 60 O 10

A G E (YEARS)

20 30 40 50 60

FIGURE 1.—Growth curves for Elephas maximus. Horizontal lines indicate the limits of size

classes; vertical lines, the approximate age equivalents of these classes. Data from:

Q Kurt and Nettashinghe (pers. comm.) / \ Hundley (1934)

% Jainudeen and Jayasinghe (pers. comm.) • Reuther (1969)

a plateau somewhere between 15 and 30 years while

the growth of males appears to continue, even if at

a slow rate for a greater period.

As the height of an elephant at birth is about 90

centimeters (Reuther, 1969) and the plateau for

Ceylon females is around 230-240 centimeters, the

size classes as determined by visual comparison can

be superimposed on these growth curves as shown

in Figure 1. The approximate age classes, which

correspond to these size classes, can be obtained by

extrapolation to the abscissa as shown in the figure.

Infants of both sexes comprise Classes 1 and 2.

Juveniles comprise Classes 3—5 for females and 3—6

for males. Subadults are Class 6 for females and 7

for males with adults 7-8 for females and 8-9 for

males.

Maberry (1962), Evans (1910:94), and others

have indicated that female Elephas can breed as

early as 6 years and males between 6 and 7. Observations from wild elephants in Ceylon have shown

that the smallest reproductively active female was

an individual in Class 5 and the smallest male

capable of obtaining an erection was an animal of

size Class 6. This would tend to indicate, as shown

in Figure 1, that puberty among wild elephants in

Ceylon probably occurs between the ages of 8

and 10. As Loxodonta is known to have a variable

age at puberty, dependent upon nutritional conditions (Laws and Parker, 1968; Laws, 1969a), it

would seem probable that this apparent discrepancy

could well be caused by the difference in plane of

nutrition between wild elephants (and domestic

animals dependent on a low plane diet) and zooraised animals. There is no reason to suspect that
NUMBER 125 11

Elephas has a fixed age of puberty. It is more

likely that this will vary with plane of nutrition as

in Loxodonta.

In field practice, elephants were classified first

into the four developmental classes, then into size

classes by comparison with a fully adult female.

The female used for this comparison was usually

the largest in the group under observation. However, since estimating the true height of an animal

in the field is unreliable at best, no such estimates

were made for groups not containing a fully adult

female. For such groups only the developmental

classes were recorded. In practice this situation

arose only with groups of males where the distinctions between adult and subadult or juvenile were

usually easy to make based on the shape of the head.

LABORATORY STUDIES

A detailed description and analysis of the results of

chemical analysis of food plants will be published

as a separate paper (McKay, Kalpage, and Jayasinghe, n.d.); only a brief summary will be included in the present work. For a detailed description of the methods used, the reader is also referred

to that paper.

The Study Area

The field work summarized in this report was all

conducted in the southeastern quarter of Ceylon in

an area extending roughly eastward from longitude

81° E. and southward from latitude 7° 45' N.

Within this region of approximately 4000 square

miles (10,400 km2) three smaller areas were

studied. The majority of the observations were

made in an area of 720 square miles (1865 km2)

surrounding the Gal Oya National Park. This

study area (Figure 2, area A) will be referred to

in this report as the Gal Oya area. Secondary study

areas were located in the region of Lahugala Tank

(Figure 3, area B), and Ruhunu National Park

(Figure 2, area C).

Extensive use is made of names of villages, rivers,

tanks, and other geographical features. To aid the

reader unfamiliar with the geography of the area,

such names are included in maps where appropriate.

A detailed map of the southeast and an annotated

gazeteer are included as Appendix 1. The following

list is useful in interpreting some of the names

FIGURE 2.—Map of Ceylon showing study areas: Arz:Gal Oya

study area; R —Lahugala study area; C-= Ruhunu study area.

encountered: Am, stream; —gala, rock, hill; —gama,

village; Ganga, river; —goda, open place; —hela,

hill; Kulam, tank or reservoir; Oya, river; Samudra,

ocean (reservoir); Wewa, tank or reservoir.

GEOLOGY AND TOPOGRAPHY

Geologically, Ceylon is divided into three major

zones: the highland series, the Vijayan series, and

the sedimentary formations (Cooray, 1967:83). The

highland series consists of khondalites, charnockites,

and gneisses of Precambrian age, and granites and

granitic gneisses of Upper Paleozoic age. This zone

extends from the southwest of the island to the

northeastern coast north of Trincomalee. The
12 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

,Danigala

2000 Paragahakelle

7 15 N

Senanayake

Samudra

/Makulassa

Yakunahela

2000

Nilgala

Bay of

Bengal

Dematapitiya

7 12 N

5 |10 15 20 25 | 30 35 40 | 45 50

MILES

 81°15'E 81°30'E 81°45'E

FIGURE 3.—Topographic profiles of two east-west sections at 7° 12' and 7° 15' N. Compiled from

Nilgala and Tirrukkovil Sheets, 1:63,360 Topographic Series, Ceylon Survey Department. Vertical

scale is 3.5 X horizontal scale.

Vijayan series, consisting of a variety of Lower

Paleozoic gneissic rocks, flanks the highland series

on the northwest and on the southeast. Sedimentary

formations, mostly of Miocene and Quaternary

origin, occur around most of the coastline.

In the area under consideration, the major portion consists of Vijayan series rocks. The transition

zone between Vijayan and highland series follows

a belt 10—15 kilometers wide running approximately between Alutnuwara, Bibile, Moneragala,

and Wellawaya. This belt corresponds to the

transition between the southeastern lowland and

the central massif. An isolated group of hills

consisting of highland series rocks occurs in the

Kataragama region (Cooray, 1967:85). In eastern

Ceylon the sedimentary formations, consisting of

littoral sands and alluvial soils, occur as a belt

10-15 kilometers wide from Batticaloa to Pottuvil

and as a narrower belt of dunes from Pottuvil to

Hambantota. Between Batticaloa and Pottuvil this

belt forms a flat coastal plain with no relief.

The highly eroded base rocks of the Vijayan

series give rise to the topography characteristic of

the eastern dry zone. The region consists mostly of

a low, gently undulating peneplain with the relief

being provided by erosion remnants. Erosion

remnants, which have resisted erosion because of

their high quartz content (Cooray, 1967), occur as

solitary rocks rising from the peneplain (Westminster Abbey, Inginiyagala), as long ridges

(Wadinagala), or as clusters of hills (Danigala,

Amunuhela, Bulupitiyahela). In the southeastern

portion of Ceylon, few of these erosion remnants

rise more than 600 meters from the peneplain.

Apart from these large hills there are large numbers

of smaller (15—30 meters) bare rocks known as turtlebacks, formed by alternate cooling and heating

and the chemical action of water (Cooray, 1967).

Within the Gal Oya region two general zones

can be distinguished. To the east the peneplain is

low (30-80 m) and is broken by a few solitary

erosion remnants and many turtle-backs. West of

a line passing approximately from Divulana via

Inginiyagala to Buddama the peneplain is higher

(150-250 in) and clusters of erosion fragments form

the dominant relief. This difference is shown on

the profiles (Figure 3) drawn at 7°12' N and 7°15'

N from the Nilgala and Tirrukkovil sheets.

Many erosion fragments have one or more steep

sides of bare rock but practically all have at least

one side with a gentle, though invariably boulderstrewn, slope. These gentler slopes are usually

forested.

DRAINAGE SYSTEMS

The southeastern corner of Ceylon can be divided

into eight major drainage systems (Figure 4). The
NUMBER 125 13

20

FIGURE 4.—Map of river drainage systems in southeast Ceylon

(figures in parentheses— area in square kilometers): 1,

Mahaweli Ganga; 2, Maduru Oya (4000) ; 3, Gal Oya

(2150); 4, Heda Oya (1170); 5, Wila Oya (650); 6 Kumbukkan Oya (1400); 7, Menik Ganga (1650); 8, Kirindi Oya

(1240).

first of these, the Mahaweli Ganga, just borders on

this area to the west and north of Bibile where it

drains only a very small portion of the land under

consideration here. The second, consisting of nine

main streams and their tributaries, drains a large

area north of a line between Bibile and Kalmunai.

These streams flow northeastward and northward.

The Gal Oya basin (Figure 4:3) consists of the

Gal Oya and three lesser streams which flow eastward. The Gal Oya was dammed at Inginiyagala

in 1918 to form a large reservoir, the Senanayake

Samudra. Most of the other streams in the area

have been dammed since that time.

The Heda Oya basin (Figure 4:4) also consists

of one major river and several minor streams, all

flowing eastward. Several small tanks (Lahugala,

Kitulana, Sengamuwa, Rote) exist in this area and

development schemes have been proposed for the

Heda Oya and Karanda Oya. All of these river

systems have some cultivation, although the Gal

Oya basin is the only one extensively developed at

this time.

The remaining three systems drain southeastward

and, with the exception of the Kirindi Oya, have

been little developed or modified.

The approximate areas of these drainage systems

are included in the legend of Figure 4. The Gal

Oya National Park is located entirely within the

Gal Oya basin, the most extensively developed of

the group. Ruhunu National Park lies along the

costal edge of the Wila Oya, Kumbukkan Oya and

Menik Ganga systems. Development of all these

systems will be considered in a later section on

agriculture.

CLIMATE AND WEATHER

Climate

The climate of Ceylon has been discussed most

recently by Gaussen, et al. (1964), Fernando (1968),

and Mueller-Dombois (1968). Gaussen, et al. (1964)

adopt an extremely complex system of climatic

subdivision in which they assign 22 types to

Ceylon based on temperature, mean annual rainfall, and number of dry months. The lack of supporting data along with their map reduces its

tlirect usefulness.

Fernando (1968:26) includes a map which shows

six bioclimatic types which, although not explicitly

stated in Fernando's text, are undoubtedly based on

the vegetation map in the same publication (see

Mueller-Dombois (1968) for critique).

Mueller-Dombois (1968) reviews all previous

attempts at classification of Ceylon's climates and

arrives at a compromise solution in which he portrays on a map a number of climatic diagrams showing the variation in rainfall patterns. He discusses

a proposed 6-7 zonal division of the climate, but

unfortunately does not include these zones on the

map itself. Although his system of climatic division

is the most logical of the three, the lack of sufficient

climatic diagrams for the southeastern region pre-
14 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

vents one from drawing accurate zones on his map

in this area.

As a result of this lack of detailed information,

I decided to compile a climatic map for the southeastern region of Ceylon. On Figure 5a, the open

circles indicate stations from which data were

obtained directly from the map in Mueller-Dombois

(1968). For the remaining stations data from the

Colombo Observatory Report (Ekanayake, 1964)

were used to prepare climate diagrams in the same

manner as Mueller-Dombois (1968). Average climate

diagrams for Batticaloa, Amparai, and Bibile are

presented in Figure 6, but on the map (Figure 5)

Batticaloa

only the summarized data for each diagram are

presented. These data are average annual rainfall,

number of rain peaks per year, and number of dry

months plus arid months per year.

Criteria for classification of months as wet, dry, or

arid follow those of Mueller-Dombois (1968:43-45)

and Walter and Leith (1960). In this scheme of

classification any month with more than 100 mm

(about 4 in) rainfall is considered wet, as any

excess above this amount is not normally absorbed

into the soil but is surface run-off. An arid month

is one where the rainfall (as plotted on the diagram) measured in millimeters is less than twice

Maha Oya

Lahugala O1650

2 3. 2

2733

'•1 Panama o) 1430

.5

Bibile

2276

Passara • 2 . 0

Moneragala

Hambegamuwa O1567

1*4

Embilipitiya 01506

Tangalle

Tanamalwila •

Katagamuwa

2\

Rainfall

peaks

Rainfall

mm

FIGURE 5.—Climatic data for southeastern Ceylon: A, Data from 19 stations showing mean annual

rainfall (large central digits), number of rain peaks per year (top digits) and number of dry

months plus arid months (bottom digits). Open circles indicate data from Mueller-Dombois

(1968); closed circles, from Colombo Observatory Report for 1964. B, Zonation within this region

based upon mean annual rainfall, number of rain peaks, and number of arid months.
NUMBER 125 15

the mean monthly temperature expressed in degrees

Celsius. The empirical formula for determining this

relationship is found in Walter and Leith (1960).

Under such conditions water generally moves upward through the soil as evaporation tends to be

higher than precipitation. This is, therefore, a

time of stress for most plants. Any month with

rainfall intermediate between this state and a wet

state is defined as a dry month.

As shown on Figure 5b, the climatic patterns can

be drawn using three criteria. The first division,

based on mean annual rainfall, with boundaries

set at 1500 and 2000 mm produces three zones

whose best fit with any published map is the vegetation map of Gaussen, et al. (1964). The second

division, based on number of peaks of rainfall

produces a narrow belt with one peak (northeast

monsoon) and a larger area with two peaks. The

third division, based on number of arid months,

shows a large southern area and narrow eastern belt

with 4-{- arid months and a larger area with 1—3

arid months.

At this point, I do not wish to enter the controversy of climatic zones. Rather I must agree with

Mueller-Dombois' (1968:56) statement that any

division of climates must necessarily depend on the

reasons for that division. In the section on vegetation, I will discuss how the division of climate

outlined above can be combined with vegetational

analysis to provide a workable climatic-vegetational

map.

Weather

The above discussion was concerned with the longterm climatic patterns, but those patterns do not

imply that each year is similar or even close to the

average at any station. A comparison of Figures

6 and 7 will show that, during the course of this

study, the patterns were definitely not average. The

only two stations for which data were available

were Batticaloa and Amparai. No data were collected by the Amparai station after 1968. Data for

1967 and 1968 were obtained from the Colombo

Observatory by kind permission of the Director;

data for Batticaloa, 1969, were obtained from

Ekanayake (1969, 1970).

During this period the rainfall pattern at

Inginiyagala closely paralleled that at Amparai. A

short drought in 1967 was broken by heavy rain in

early October. In 1968 a brief but severe drought in

February was broken by rains in March and April,

followed by another severe drought which was

broken by thunderstorms in July and August. At

the end of the northeast monsoon in January 1969,

the Gal Oya National Park area was essentially

rainless (except for occasional short showers) until

September.

Apart from the importance of droughts and rainy

periods in determining elephant movements, the

weather patterns have another important effect on

the present study. Thunderstorms may occur at

any time of year but data from Batticaloa (1967-

1968) show that they were most frequent from

April to October. Normally electrical storms are

accompanied by heavy rain, but if they come after

a long period of drought or if the storms are dry

then the lightning can produce grass fires in the

savanna areas. As most of the grass fires in this

area are set by man, a discussion of fire in general

will be postponed, but it should be emphasized here

that lightning-started fires do occur (three were

observed by the author to be started on the night

of 18 June 1968 in the Nilgala area).

In the Gal Oya area, natural water holes are

scarce, most free water existing either in streams or

man-made tanks and irrigation ditches. During

drought periods, such water holes as exist generally

dry up rapidly as do many small streams. Some

streams, however, retain subsurface water in sandy

pockets even in the driest weather.

In Ruhunu National Park during the period of

study (June to September 1967), the area was

under a typical drought with occasional showers.

During this time many water holes dried totally.

The patterns observed at this time will be discussed more completely in considering the effects

of climate and weather on elephant movements.

SOILS

As with the problems of classifying Ceylon's climate,

there are several opinions on classification and distribution of soil types (see Kalpage (1967),

Panabokke (1967), and Fernando (1967)). Panabokke's (1967) map is the most detailed of the

three and is the only one to give the source of data

used in its compilation. According to him the soils

of the area are predominantly reddish brown (of

three subtypes) with alluvial soils along river-
16

Bibile

500 1

250

E

E 100

5 75

50

25

0

JFMAMJJASON D

5 0 0

2 5 0

100

30

20

10

0

75

5 0

25

0

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

BattJcaloa

JFMAMJJASON D

30

20

10

0

Temp

°C

Amparai Hambantota

500 n

2 5 0

100

B

c 75

a

at

5 0

25

J FMAM J JASON D

5 0 0

2 5 0 •

100 •

75

5 0

25

JFMAMJJASON D

FIGURE 6.—Average climatic data for four stations in southeastern Ceylon. Data from Batticaloa,

Bibile and Hambantota are based on 30 year averages (1931-1960); those from Amparai, on

10 year average (1951-1960). All data obtained from Colombo Observatory Report for 1964.

Temp

°C
NUMBER 125 17

Amparai

5 0 0

250

100

5 75

a:

50

25

0

500

250

E

_ 100

a

"c

£ 75

50

25

JFMAMJJASOND J FMAMJJASON D

Batticaloa

30

20

10

Tem p

•C

JFMAMJJASONDJFMAM J JASOND J FMAMJJASON D

1967 1968 1969

FIGURE 7.—Rainfall and Temperature Conditions at Batticaloa and Amparai, 1967-1969.

bottoms and sandy regosols along the coastal strip.

The effect of soil types of vegetation in Ruhunu

National Park will be considered by MuellerDombois (n.d.).

VEGETATION

Types and Distribution

Gaussen, et al. (1964) list three major vegetation

zones for the southeast: (1) Manilkara-Chloroxylon

series, (2) Chloroxylon - Berrya - Vitex - Schleichera

series, and (3) Filicium-Euphoria-Artocarpus-Myristica Transitional series. As they do not state how

they collected their data and (for the Gal Oya

region at least) as Euphoria is a dominant in their

Zone 2, their classification cannot be considered

adequate.

Fernando (1968) gives a more adequate descrip-
18 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

tion of the forest types and their species composition.

According to his map there is a small area of

monsoon scrub jungle in the area of Ruhunu National Park, a wide belt of monsoon forest inland,

and a narrow belt of intermonsoon forest and

savanna west of the Senanayake Samudra and

Moneragala.

McCormack and Pillai (1961a,b) have analyzed

the composition of the forests in eastern Ceylon

and by comparison of their maps with aerial

photographs it would appear that their categories

correspond roughly to mine:

7MD=medium stature forest; 7LD=low stature

forest with emergents; 7ND=forest scrub. In these

and other publications in the same series, they

have divided the forests of Ceylon into three categories (wet, intermediate, and dry). Their category

of dry forest includes the arid zone of Fernando

(1968) and others.

It was not possible in this study to survey forest

types over a sufficiently large area to make any

attempt to resolve these differences for the entire

area. It is, however, possible to propose a tentative

classification for the region surrounding the Gal

Oya National Park. Mueller-Dombois (n.d.) will

provide an even more detailed analysis for the

Ruhunu National Park.

From the mosiac aerial photographs published by

the Ceylon Survey Department (scale 1:31680) it

is possible to distinguish five major vegetation types

(forest, savanna, forest scrub, scrub, grassland) as

well as modified types (e.g., paddy land, chena).

Vegetation maps were prepared for the area around

the Gal Oya National Park, extending eastward to

the coast, by outlining the areas on the mosaics

and tracing onto plastic overlay sheets. These

working maps were used to prepare Figures 11

and 12.

These maps can then be used as a basis for

defining most of the vegetation types. In order to

determine what differences, if any, existed among

forests in this region, 15 plots were sampled along a

35-mile strip roughly following a 10-mile wide belt

from Bulupitiya in the west of Akkaraipattu on

the coast. Five of the plots were in savanna, the

remainder were in forest. The dominant species in

each plot sampled were recorded and samples of

species unidentifiable in the field were collected for

subsequent identification. Except in three savanna

plots, no quantitative data on species composition

and abundance were collected.

Figure 8 shows the location of plots surveyed and

the distribution along the 35-mile strip of 5 grasses,

20 trees and shrubs, and 3 herbs. The grasses are

those which were dominant in savannas {Themeda,

Cymbopogon, Imperata) or man-made, tankside

grasslands (Brachiaria, Cynodon). The first six

trees are savanna species; the remainder (with the

exception of Bauhinia), forest species. The three

herbs were typical of disturbed (roadside, abandoned chena) habitats.

In the extreme west are found forest and savanna

types. The forest is generally evergreen, of medium

stature (30—40 m), with a dense closed canopy layer,

a dense subcanopy of shorter trees and saplings and

a relatively sparse shrub layer. Ground vegetation

is sparse and throughout the year there is generally

a layer of leaf litter 2-3 cm deep. Dominant species

in the canopy and subcanopy strata are: Artocarpus

sp., Berrya cordifolia, Euphoria longana, Mangifera

zeylanica, Diospyros spp.; other species present include: Schleichera oleosa, Pterospermum canescens,

Elaeodcndron glaucum, and Semecarpus obscura.

The shrubs and sapling layers consist of Mallotus

repandus, Polyalthia spp., and Celtis cinnamomea,

among others. These forests occur as large tracts

and as galleries along rivers. In the latter situation,

Terminalia arjuna is generally present.

The western savanna (Singhalese: Talawa) is

primarily tree savanna with areas of savanna woodland (Hopkins, 1965) with trees of relatively even

height (10-15 m) and trunk diameter (15-30 cm

dbh). Over much of the area the trees appear to be

relatively evenly spaced (Figure 9) and often occur

as single-species stands as illustrated by plot 2 on

Table 1. Although the density of trees in this

savanna is high as shown in Table 1, the crowns

are sparse and nonoverlapping. Dominant species

are Terminalia chebula, Terminalia belerica,

Pterocarpus marsupium; also present are: Butea

monosperma, Careya arborea, Anogeissus latifolia,

and Cycas rumphii. Shrubs present are Phyllanthus

emblica and Zizyphus sp. The dominant ground

vegetation consists of tall, perennial grasses, the

commonest of which are Cymbopogon confertiflorus

and a Themeda (identified by Fernando (1968) as

T. tremula, but from Senaratna's (1956) description

appears to me to be T. triandra).
NUMBER 125 19

Themeda sp.

Cymbopogon confertiflorus

Imperata cylindrica

Brachiaria sp.

Cynodon dactylon

Pterocarpus marsupium

Terminalia chebula

Butea monosperma

Phyllanthus emblica

Careya arborea

Cycas rumphii

Artocarpus nobilis

Po I y a 11 h i a s p.

Euphoria longana

Berry a cordifolia

Pterospermum canescens

Schleichera oleosa

Strychnos nux-vomica

Sterculia foetida

Drypetes sepiaria

Manilkara hexandra

Euphorbia antiquorum

Maba buxifolia

Memecylon umbellatum

Bauhinia racemosa

Lantana aculeata

Mimosa pudica

Ipomoea sp.

PERCENT

SAVANNA

ZONE

>50

25-50

10-25

1-10

0

HUMID DRY ARID

FIGURE 8.—Distribution of plants along a 35-mile strip in the Gal Oya region. For the grasses

and savanna trees, the dark gray indicates presence as a dominant and white presence, but not

dominant. For the forest trees the stippled area indicates presence as a dominant. The dry zone

and arid zone contain relatively little savanna, while the humid zone and both ecotonal areas

contain large proportions of savanna. Towns as marked from west to east are: B, Bulupitiya; M,

Mullegama; N, Namal Oya; I, Inginiyagala; D, Damana; A, Amparai; Ak, Akkaraipattu.

Many other species besides those listed above

occur in this area but these appeared to be the

most characteristic of the Gal Oya region. Fernando

(1968) lists a number of additional species, several

of which were neither collected nor observed in

our work.

As one moves eastward the species composition

of the forest changes. Detailed surveys using quantitative techniques would be necessary to confirm

the impression that the change is gradual. Artocarpus and Polyalthia become scarce east of Mullegama

as do Mangifera and Celtis. East of the MullegamaNamal Oya region the talawa becomes less extensive and occurs only as small patches or islands,
20 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FICUKE 9.—Savanna woodland (Talawa) in western sector of Gal Oya National Park.
NUMBER 125 21

TABLE 1.—Flora composition of two areas of savanna (Talawa) (Figures in parentheses = total

vegetation living and dead; other figures = living

vegetation.)

Vegetation

TREES (>5m)

Terminalia cliebula

Anogeissus latifolia

Pterocarpus marsupium

Careya arborea

Adina cordifolia

Phyllanthus emblica

Butea monosperma

? dead

Total

Trees per hectare

SHRUBS (<5 m)

Phyllanthus emblica

Zizyphus sp

Careya arborea

Terminalia chebula

Cycas rumphii

Butea monosperma

Unidentified

Total

Shrubs per hectare

No. in

Plot 1 *

No. in

Plot 2**

33

2

30

3

3

1

1

9

82 (91)

328 (364)

7

8

0

3

0

0

0

18

72

97

0

0

0

0

0

0

19

97 (116)

388 (464)

2

2

3

0

3

2

1

13

52

•Plot 1: 124 m N of Gal Oya, 100 m E of road from

Bulupitiya to Medagama; 100 m to nearest forest (gallery);

area: 0.25 hectares (50 x 50 m).

••Plot 2: 2 km S of Bulupitiya on road to Medagama, 30 m

E of road; 2 km to nearest forest; area: 0.25 hectares (50

x 50 m).

surrounded by forest.

Within this area east of Mullegama, the forest

gradually becomes of lower stature (20—35 m) and

contains more individuals of deciduous species as

can readily be seen during the dry season. Euphoria

longana and Berrya cordifolia remain common,

Ptcrospermum and Schleichera become more common and Strychnos, Diospyros malabarica, and

Drypetes appear as dominant subcanopy species.

Manilkara and Euphorbia occur in rocky areas and

Sterculia foetida appears as an emergent. At least

two species of Ficus occur and in places may be

quite common, but their distribution does not appear to be as even as that of the others.

As one moves eastward between Inginiyagala and

Amparai, the species composition of the forest

appears to remain stable but the character of the

canopy layers changes from a dense medium stature

canopy to a dense low stature canopy with emergents. Species such as Drypetes, Pterospermum, and

Glenniea which form a subcanopy around Inginiyagala are in the now lower (15—20 m) canopy,

5 miles further east, and those such as Berrya,

Schleichera, and Sterculia occur as emergents along

with Chloroxylon and Diospyros spp. Throughout this area the shrub layer is relatively sparse,

consisting mostly of saplings of Pterospermum and

several species of shrubs.

East of Amparai the general character and composition of canopy and emergents changes little

except for the addition of Manilkara as a common

emergent. The main difference now is in the shrub

layer which becomes dense, consisting of Memecylon

spp., Maba buxifolia, and Bauhinia recemosa. Close

to the coast, the number of emergents becomes less.

This type can be referred to as a forest scrub (see

Mueller-Dombois, n.d.).

In the area around Amparai a type of savanna,

different from the talawa, exists. In this area the

dominant grass is Imperata cylindrica. Shrubs of

practically all species in the surrounding forest

occur in islands within the grassland and Bauhinia

racemosa, Phyllanthus emblica, and Butea monosperma occur as solitary individuals. Figure 10

shows a typical portion of this shrub savanna.

Examination of Figure 8 shows that there is a

west-east gradient in the distribution of forest and

savanna plant species along the 35-mile strip. These

data may be combined with the climatic data presented in Figure ba and bb to make a tentative

classification of climatic/vegetational zones.

The area of medium stature forest and talawa

falls within the /one of >2000 mm annual rainfall.

East of this is a /one with 1500-2000 mm annual

rainfall, two or fewer arid months and 3—4 dry

months. This zone corresponds to the EuphoriaPterospermum-Drypetes forest (low stature with

emergents) and can be considered a dry zone.

The resemblance of the vegetation between

Amparai and Akkaraipattu to that of Ruhunu

National Park (Mueller-Dombois, n.d.) indicates

that this region should be considered an extension

of the "arid zone." I hypothesize that a single peak

rainfall, followed by a prolonged period of drought

(1-|- arid months plus 1-3 dry months) may be

another factor determining the presence of arid
22 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 10. —Shrub savanna, three miles north of Amparai.

zone vegetation besides low rainfall per se. Certainly

from the data available, it is more reasonable to

extend the limits of arid zone vegetation northward

along the coastal plain to some point north of

Batticaloa.

While it can be seen that there are these three

major types, it must also be emphasized that they

are separated, not by discontinuities which can be

drawn as lines on a map, but by transitional zones

which in some places may be as wide as the typical

"/one" itself (Figure 8).

Over large sectors of this region man has practiced a type of shifting agriculture, referred to

locally as chena (from Sinh: "Hen"), in which areas

of forest are partially cut, burned, cultivated for a

few seasons, then abandoned. In some places this

activity has been extensive over a long period of

time and much of the forest is actually a mosaic of

small areas at different successional stages. Such

areas are recognizable from the aerial photographs

and are distinguished on the vegetation map

(Figure 11) as "forest-chena" (Figures 11 and 12

show the results of vegetation analysis for the Gal

Oya National Park and the area surrounding

Amparai, respectively).

Within the Gal Oya National Park, forest is the

predominant vegetation type covering 45 percent

of the total area (Table 2). Forest affected by chena

occupies 2.7 percent and is concentrated in the

southern part of the park near the village of Baduluwela. Talawa savanna makes up 33 percent of

the total area and is the dominant type in the

western sector of the park.

The grassland is entirely artificial, created by

logging in the bed of the reservoir and by periodic

inundation of the land. The measurements in Table

2 were made from a photograph taken when the

water was at a relatively low level. At extreme high

water the area of grassland will be reduced drastically except in a small area south of Inginiyagala

where land above the level of the reservoir was

cleared.

Grassland of this type occurs around all of the

tanks in this region. Except for a few small holding

tanks, which are supplied by larger tanks, all of

the reservoirs have a fluctuating water level, being

normally high during the northeast monsoon and

becoming progressively lower until the next rainy

season. Grass growth begins soon after the water

recedes. In lower lying areas, which are inundated

for long periods annually, the common grasses tend

to be annuals (e.g. Eragrostis, Eleusine) . In the
NUMBER 125 23

Key to vegetation types

F Forest

Fc Forest(chena)

5 Savanna

G Grassland

W Water

R Rock

FIGURE 11.—Vegetation map of Gal Oya National Park.
24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 12.—Vegetation map of the area surrounding the Amparai Sanctuary. A = agriculture;

F—forest; Fs—forest scrub; G=grassland; S =: savanna; W —water.

TABLE 2.—Composition of vegetation in Gal Oya

National Park (calculated from Figure 11).

Vegetation

Forest

Forest (chena)

Savanna (Talawa)

Grassland

Water

Bare rock

Total

Area

mi'

62.16

3.79

46.12

12.48

13.77

0.05

138.37

km'

160.99

9.82

119.45

32.32

35.66

0.13

358.38

Percentage

45.0

2.7

33.3

9.0

9.9

0.1

100.0

higher areas, which may not be submerged every

year, perennials (Cynodon dactylon, Brachiaria sp.)

become more common. In extremely high areas of

the Senanayake Samudra which are often dry for

several years, other plants, such as vines (Mimosa

pudica and Ipomoea sp), may become abundant

and termites may move in from the forest (Figure 13).

Phenology

Although no study of phenology was made in the

forests of the Gal Oya region in connection with
NUMBER 125 25

FK;URK 13.—Upper bank of Senanyake Samudra at Kossapola. Note the presence of a few dead

trees on the upper bank. At the time this photograph was taken (1968) this section of bank

had been dry for several years and termites had invaded from the forest.

this work, the data obtained by Koelmeyer (1960)

and by Muckenhirn and Rudran (n.d.) show conclusively that within the drier regions of Ceylon

there is a definite seasonality in the leaf fall, flushing, flowering and fruiting of many forest trees

and that different species demonstrate particular

patterns. The significance of these phenomena to

the elephant is that not all potential food types are

available in equal abundance at all times of the

year.

Seasonal differences in availability are particularly

apparent when one looks at the grasses. Figure 14

shows the condition of grasses in the talawa around

Nilgala from late 1967 to 1969. Throughout this

period of 26 months, fresh green grass was available

for only 12 months.

Fire

Toward the end of the rainy periods the grass

culms, which have been growing for several months,

begin to die. After only a few weeks of drought

these dried stems and leaves are readily ignited.

Fires may be started by lightning or by man. Manmade fires observed in this particular area were

started in three major ways: (1) fires set by poachers,

(2) spreading of camp fires—poachers, fishermen,

carters—and (3) fires set by cattle-herders who

know that a fresh growth will follow with the next

rains.

As most fires occur during the period of the southwest monsoon, when a dry steady wind (kachan)

Fires

68

D'J

69

FIGURE 14.—Changes in quality of grass in relation to weather

and fires. The dark-stippled area shows those periods when

fresh grass was available; the lightstippled area, dry grass.

Vertical scale is in arbitrary units and gives the approximate

relative availabilities of fresh and dry grass.
26 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 15.—Savanna woodland (Talawa) after fire, September 1967.
NUMBER 125 27

FIGURE 16.—Shrub savanna after fire, June 1969.
28 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

blows continuously during the daytime, extensive

areas are burned almost every year. Approximately

50-75 percent of talawa in the region of Bulupitiya

and Nilgala were burned in all three years of this

study. Over most of the talawa area the fires are

restricted to the savanna, the forest remaining unaffected. In only one small area (plot 2 in Table 1)

were any appreciable number of savanna trees

affected by the fires. In this area some 15—20 percent

of the Terminalia chebula had burned bark and

were leafless at the time the plot was sampled

(about 6 weeks after burning). The shrubs, however, were apparently unaffected.

The potential effects of fire on grassland and

savanna, discussed extensively by Daubenmire

(1968) and Hopkins (1965), are numerous including changes in productivity, species composition,

and cover type. Although it was not possible within

the time limit of this study to examine any of these

effects in detail it was apparent that the fast-moving

fires of the talawa in general have little effect on

species composition. As noted by Daubenmire

(1968), a slow-moving hotter fire is capable of producing greater effects on the ecosystem. Such effects

were noticeable in the savanna areas in the vicinity

of Amparai, where, in the extensive fires of May

and June, 1968, shrub areas bordering on the grassland were frequently burned. Shrubs as far as

1—1.5 m away from the grass died as a result of these

fires. Figures 15 and 16 show the effects of fire on

the two savanna types, including the affected shrubs

in the shrub savanna.

HISTORY OF DEVELOPMENT

Although accurate records are not available, the

ruins of a reservoir at Digavapi (east of Amparai)

and remains of temples scattered throughout the

region indicate that man has been present in some

numbers for several hundred years and that cultivation may have been extensive during the Polonnaruwa period. Accounts by Knox (1681) and other

early European visitors indicate that the town of

Batticaloa remained an important population center

and that the coastal strip was probably inhabited

and cultivated continuously. Farmer, et al. (1970)

refer to construction of an anicut and two tanks

(Amparai Kulam, Kondavatavan Kulam) between

1856 and 1892 and state that by the early part of

this century there were some 83,000 people living

in the Gal Oya region. Of these, 79,000 were concentrated in the rice-growing land and on the coastal

sandbars, with 4,000 scattered among several villages

in the upper reaches of the valley, living mostly

by chena cultivation.

From 1949 to 1951 an earthen dam and a concrete

dam were constructed at Inginiyagala, blocking the

Gal Oya and creating the reservoir known as the

Senanayake Samudra. In the decade following, a

series of irrigation ditches was developed along the

left (north) bank and minor dams were constructed

across the Namal Oya, Andella Oya, and Navakiri

Aru, among others. During the 1960s work was

begun on development of the right bank, including

an irrigation channel from the Senanayake Samudra

and minor tanks on the Pallang Oya, Ekgal Aru,

Ambalam Oya, and Pannela Oya. Construction in

this region is still in progress.

The population of this area has risen dramatically. In 1950-1951, 296 families were settled in the

region; by 1965 the number of newly settled families

was 11,936 (Farmer, et al., 1970). Data from the

Ceylon Department of Census and Statistics (Yearbook, 1967) show the 1963 population of the

Amparai district as 211,820. More recent figures

are not available.

AGRICULTURE

Figure 17 shows the approximate distribution of

agricultural land (small areas of chena are omitted)

as of 1969 and projections for future development

by the River Valleys Development Board.

Agriculture in this area is of two types, intensive

and shifting. Intensive agriculture may be of either

the upland type (e.g., plantains, pineapples,

coconut) on well-drained hillsides or of the irrigated

type (sugar cane, paddy) in the bottomlands. In

either case intensive agriculture involves clearcutting of the original vegetation and maintenance

of cultivated plants.

Chena farming, however, involves only partial

cutting of the forest followed by burning. The

land is then cultivated for one or two growing seasons with minimal disturbance of the soil, then

abandoned. This land then quickly reverts to

natural vegetation. The first stage, (Figure 18) in

this succession generally consists of woody herbs and

low shrubs (Lantana aculeata, Ochna zeylanica,
NUMBER 125 29

KEY

DEVELOPED LAND

NATIONAL PARK

o

7 15

7°OO'

"6" 45

81 15 81 30 81 45

FIGURE 17.—Distribution of agricultural land in the Gal Oya region. Shaded area includes land

developed as of October 1969.

and Premna latifolia), followed by larger shrubs

and trees. During this early stage of succession such

areas are heavily used by elephants.

Under the traditional methods of cultivation,

discussed in detail by Wikkramatileke (1963),

paddy lands generally lay close to the village. Such

areas were surrounded by an expanse of relatively

depauperate vegetation (due, in part, to grazing

by livestock and cutting for fuel). This is, in turn,

surrounded by areas of chena and forest. With this

pattern of land usage, the contact between wildlife

and man would be relatively slight and would be

confined mostly to the chena zone. Under modern

agricultural conditions, however, large areas of

intensive cultivation (sugar cane, paddy) juxtapose

forest land (Figure 19). This provides ample opportunity for elephants, wild buffalo, and swine to

feed on cultivated crops, often causing considerable damage.

Besides cultivation, man also affects the environment through the grazing of domestic livestock.

Cattle (zebu), buffalo, and goats are the principal

species, and all are allowed a certain amount of

freedom to forage in the forest surrounding the
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 18.—Chena land abandoned about two years previous to time photographed.

villages. In some areas cattle and buffalo may be

herded into large groups. Such large herds occur

in the region around the Amparai airport (cattle)

and in the eastern half of the Gal Oya National

Park (buffalo). Apart from the effects of grazing

by the animals, the vegetation may also be altered

by man, through the setting of fires to promote

new grass growth.

Figure 20 shows the relationships between the

various vegetation types in this region. The double

arrows indicate changes that cattle-grazing and

man through chena cultivation can effect on these

vegetation types.

A third effect of man on the environment lies in

the construction, use, and abandonment of tanks

or reservoirs. When in use, a tank generally has a

forested catchment area. The boundary between

forest and water provides for the elephant not only

a source of water, but often a source of food. When

such tanks are abandoned or poorly maintained

(e.g., Lahugala, Figure 21) silt accumulates and

vegetation invades the tank beginning with lotus

(Nelumbium) and a number of grasses, notably

paddy (Oryza saliva). Such unused tanks provide

a rich source of food for the elephant, particularly

at the onset of the rainy season.

DEFORESTATION AND AFFORESTATION

Apart from cutting for agricultural purposes, large

areas of land have been logged for commercial

timber. In some areas the logging is selective as

recommended for this region by McCormack and

Pillai (1961a,b) but in other areas tracts have been

clear-cut. Several of these areas (and some areas of

grassland) have been planted with teak (Tectona

grandis) in an attempt to provide more valuable

timber. The teak trees have been planted, in
NUMBER 125 31

FIGURE 19.—Paddy land showing juxtaposition of cultivated area with forest.

monoculture, relatively close (3—5 m) together.

Szechowycz (1953) considered that these plantations were unsuitable for the area and that the

project should be halted as tree growth was apparently impaired. Few shrubs occur in the teak

plantations and grasses are primarily Imperata

cylindrica and Cymbopogon confertiflorus.

THE VERTEBRATE FAUNA

Terrestrial mammals known to be present in the

area are listed in Table 3. Insectivorous bats are

seasonally common, especially in the moister areas,

but attempts to catch individuals for identification

were largely unsuccessful. Fruit bats (Pteropodidae)

may occur occasionally but none were observed

during this study.

Of the mammals listed in Table 3, the two

primates, the hare, the wild boar, the deer, and

buffalo are important herbivores in addition to the

elephant (see pp. 97-99).

The only large predator in the whole of Ceylon

is the leopard (Panthera pardus), which around the

Gal Oya National Park, consists of not more than

three pairs. Several smaller predators are also

present. Of these, the jackal (Canis aureus) and

two species of mongoose (Herpestes smithi and H.

vitticollis) feed from carcasses of elephants and

other ungulates.

Comparison of Table 3 with the report for

Wilpattu by Eisenberg and Lockhart (1972) shows

that the total number of mammalian species present is roughly the same although the species composition of the two areas differs. Wilpattu has a

higher diversity of primates and carnivores and a

lower diversity of rodents than Gal Oya. In most

instances these differences would appear to be due

to species whose ranges are restricted to either the
32

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

CHENA

FIGURE 20.—Vegetation types in the Gal Oya region and changes due to cultivation and grazing.

Chena cultivation partially clears land, which soon reverts to previous forest type. Grazing

appears to have a longer-lasting effect in hindering return of the previous forest type; succession

may be much slower in heavily over-grazed areas. tS —tree savanna; mF—medium stature

forest; IF (E) —low stature forest with emergents; FSc=forest scrub; Sc(E)=rscrub with emergents; Sc=:scrub; G/Sc=grass with scrub islands; sSzrshrub savanna; G —grassland.

northern or southern half of the dry zone (Eisenberg and McKay, 1970) rather than to ecological

differences.

Of the more than 300 species of birds which occur

regularly in Ceylon (Phillips, 1953), 150 were

observed in the Gal Oya region. I do not intend

to discuss these in any detail in this paper, but two

ecological categories of birds deserve mention. First

are the large numbers of fish-eating birds which

occur on and around the tanks. Besides the numerous pelican, cormorants (three species), herons

and fishing eagles (Ichthyophaga ichthyaetus and

Haliaeetus leucogaster), there are large numbers of

Brahminy kites (Haliastur indus) around the

Senanayake Samudra whose food consists largely of

fish.

The second group consists of such frugivorous

birds as hornbills (Tockus griseus and Anthracoceros

coronatus), pigeons (Ducula aena and Treron (2

species), parrots (Psittacula (3 species) and Loriculus beryllinus), and barbets (Megalaima (3

species)). Besides the potential effect these birds

may have on dispersal of tree species, they may also

have an effect as competitors with primates.

Among the reptiles present in the area, crocodiles

(Crocodylus palustris) are locally common in tanks

and irrigation ditches and the Thalagoya (Varanus

bengalensis) is abundant in drier areas. Rat snakes
NUMBER 125 33

FIGURE 21.—Lahugala Tank showing dense growth of grasses.

(Ptyas mucosus) are very abundant but venomous

snakes (Naja naja and Vipera russelli) and the

python (Python molurus) are only locally common.

Several species of gekko are found and two Agamids

(Calotes spp.) and a skink (Mabuya sp.) are very

abundant. Freshwater turtles (Melanochelys trijuga

and Lissemys punctata) are abundant in irrigation

ditches.

Amphibians include Bufo melan.ostictis, Rana

tigrina, Rana limnocharis, Rana gracilis, and

Rhacophorus cruciger.

Tanks throughout this region have been artificially stocked with fish, principally Tilapia

mossambica.

THE INVERTEBRATE FAUNA

It would be absurd to attempt any compilation of

the invertebrate fauna of this region. Only those

forms of particular importance to the elephant

will be mentioned.

Aquatic leeches occur in many of the tanks in

this region and are particularly abundant at

Lahugala. Terrestrial leeches (Haemadipsa sp.)

occur only in moister areas around Kossapola,

Baduluwela, and Bibile.

Two types (which I was unable to identify as to

species) of termites occur in this region: a moundbuilding type which is commonest in the driest

areas and a nonmound-builder which occurs in the

moister forests to the west. The potential relationship between termites and elephants are

discussed on page 100.

Three major groups of biting arthropods (mosquitoes, flies, and ticks) are seasonally abundant.

Mosquitoes of several species and biting flies-

(Tabanidae) are more abundant during the wetter

months, while ticks appear more commonly in the

drier months.

Populations

Two terms—population and herd—will frequently

be used. Population means the total number of

elephants inhabiting a given geographic area. For

some of the populations of elephants in Ceylon

the boundaries can be demarcated by zones in which

elephants apparently do not occur or are rare; for

others the dividing line is arbitrary. I define "herd"

as a group of elephants consisting of related adult

females and their juvenile offspring who maintain

a certain degree of internal organization and who

do not associate over long periods of time with

other such groupings. A more complete description

ot the herd and its social organization is given on

pages 72-75.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABLE 3.—Mammals of the Gal Oya Region

Family and species Comments Family and species Comments

Soricidae

Suncus murinus kandianus

Cercopithecidae

Presbytis entellus thersites

Macaca sinica sinica

Manidae

Manis crassicaudata

Sciuridae

Petaurista petaurista

Ratufa macroura

dandolena

Funambulus palmarum ssp.

Hystricidae

Hystrix indica

Muridae

Tatera indica

Mus musculus

Mus cervicolor

Mus fernandoni

Rattus blanfordi

Rattus rattus ssp.

Millardia meltada

Widespread and locally

abundant in moisture

areas

Common throughout the

area; higher density in

the eastern half

Common in eastern half of

the area, sparse to the

west

Sparsely distributed in the

east only

Reported from Inginiyagala

Common throughout the

area

Common

Widespread but sparse

Very abundant in open areas

Common around villages

Common to abundant around

paddy fields

Reported, but not observed

during 1967-1969

Reported, but not observed

during 1967-1969

Common around villages

Reported, but not observed

during 1967-1969

Leporidae

Lepus nigricollis singhala

Mustelidae

Lutra lutra nair

Canidae

Canis aureus lanka

Ursidae

Melursus ursinus

Viverridae

Viverricula indica

Paradoxurus hermaphroditus

Herpestes smithi

Herpestes vitticollis

Felidae

Felis viverrina

Panther a pardus fusca

Elephantidae

Elephas maximus maximus

Suidae

Sus scrofa cristatus

Tragulidae

Tragulus meminna

Cervidae

Muntiacus muntjak malabaricus

Axis axis

Cervus unicolor

Bovidae

Bitbalus bubalis

Very abundant in open areas

Widely but sparsely

distributed

Common throughout

Locally common

Common

Present but not common

Locally very common

Disjunct distribution, but

common around

Inginiyagala

Sparse

Sparse

Common

Locally common

Sparsely distributed in

forested areas

Sparse in forest areas

Locally common

Sparse but widespread

throughout forested areas

Locally common

DISTRIBUTION OF POPULATIONS

Within the southeast quarter of Ceylon there appear to be three populations. One population

inhabits the area around the Gal Oya National

Park; the second, from Rufus Kulam and Lahugala

Tank to approximately the Kumbukkan Oya; and

the third, the area around Ruhunu National Park.

Most of the data concern the first two. Within

each of these two populations there is some

overlap between the home ranges of their constituent herds, but a minimal overlap between populations. Figure 22 shows the distributions

and sizes of the herds within the Gal Oya population and the approximate limits of the Lahugala

area population. Herd ranges for this latter population are not shown on this map as it was not

possible during this study to delimit these with any

accuracy. As can be seen from this figure, the

distribution of elephant herds is not uniform.

Ranges I and III contain relatively low numbers of

animals, between 15 and 25 in each; whereas areas

II, IV, V, and VI contain larger numbers. Areas

I and III contain approximately equivalent amounts

of forest and savanna land while area II is predominantly savanna with some scattered forest

blocks. The remaining areas are primarily forest.

There does not appear to be any correlation between the type of vegetation predominant in an

area and the numbers of elephants that will be

present.

The ranges of these groups show a certain

amount of overlap with the exception of area VI.

It is quite probable that this spatial separation of

the latter herd is due not to any traditional movement patterns but to the isolation of this area by

surrounding agricultural land. The land lying
NUMBER 125 35

KaVmunai

Moneragala ttuvi l

7°30

7 1 5

O i

7 00

6°45'

81 15 8130 8145

FIGURE 22.—Distribution of elephants and population sizes in eastern Ceylon. The herds within

the Gal Oya population arc: I Northern Park, II Talawa, III Baduluwela, IV Hatpata, V

Ambalam Oya, VI Amparai. The upper digits give the estimated number of adult males living

within the range of the herd; the lower digits are the estimated sizes of the herds.
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

between area VI and areas I, IV, and V, which is

primarily cleared for agriculture, is occupied only

by strays, usually adult males, although on occasions

the herds from area I and area VI will invade this

region of paddy land.

It is estimated that the total population in this

area is between 260 and 300 elephants including

adult males. The total population size for the area

surrounding Lahugala Tank is estimated to be

approximately 150.

Figure 23 shows the relationship of these two

populations to the other populations of elephants

in Ceylon with a rough estimate of the total population of the island. Estimates of any reliability

FIGURE 23.—Estimated elephant population of Ceylon, 1969

Areas with most reliable estimates are enclosed in solid lines;

others in dashed lines.

are available for only four major areas: The Gal

Oya and Lahugala areas included in this study, Wilpattu, Tamankaduwa, and Ruhunu National Park.

Eisenberg and Lockhart (1972) have estimated that

there are approximately 120 elephants in the area

around Wilpattu National Park. My estimate for

the Ruhunu National Park region is approximately

150. Nettasinghe (pers. comm.) estimates approximately 400 for the population in the Tamankaduwa

area.

The other areas shown enclosed in dotted lines

on Figure 23 are not so well known. Wickremasinghe

(pers. comm.) informs me that the area between

Gal Oya and Polonnaruwa is relatively sparsely inhabited by elephants and observations from several

trips made by the author through this area would

tend to support this in that very few signs of elephants were seen when traveling through either

the western or northeastern portions of this area.

The reason for the relative scarcity of elephants in

this area is unkown, although an examination of

aerial photographs and observations made during

a flight over this area in 1968 showed that this

area had been subjected to quite intensive chena

agriculture for some time. It appears possible that

this intensive activity by man has forced the elephants out of this region. Area III lying between

Dambulla on the west and Trincomalee in the

northeast and including a large portion of the

lower Mahaweli Ganga contains, according to

Nettasinghe, (pers. comm.), about 400 elephants.

It is possible that certain of the animals living to

the west of Polonnaruwa do not congregate in the

Tamankaduwa area closer to the mouth of the

Mahaweli; therefore, this population may actually

be as high as 500 to 700 animals. The relatively

large area in the northern portion of the island

(Figure 23: area II) was not surveyed in any detail

either by myself or by Eisenberg and Lockhart

(1972), although I did make two trips into this

area. This region is characterized by an interspersion of forested areas and agricultural land. Several

herds are known to be present around Giant's Tank,

Vavuniya, and Galenbidunu Wewa. The total

population in this area is probably between 200

and 500 elephants.

The areas to the north and to the west of the

Ruhunu region are again characterized by interspersion of forested areas and agricultural land and
NUMBER 125 37

probably contain between 75 and 150 elephants.

The remaining four regions are relatively small

isolated forested areas: in the vicinity of Hiniduma

in the southwest, Deniyaya, and Adam's Peak in the

central highlands and Deduru Oya in the northwest. These areas all contain isolated herds which

are low in number. Thus, a minimum figure for

the total elephant population of Ceylon would be

between 1600 and 2200. This estimate agrees closely

with that of Norris (1959), although Norris did not

give any detailed account of distribution of elephants or reasons for arriving at his 1951 figure

of 1500.

I cannot stress strongly enough that my estimate

is only a first approximation, based upon the numbers known to be present in a few areas and, by

extrapolation, the assessment of a minimum population to those areas not censused.

If the supposition of a possible elephant population of 12,000 at the beginning of the 19th century

(p. 5) is correct, the present population represents about 15 percent of that one-time total. The

only comparable estimates for other Asian countries

are those of Medway (1965) and Stevens (1968)

who show a total of about 500 elephants in 50,000

square miles (129,500 km2)—a density much lower

than that now existing in Ceylon.

POPULATION STRUCTURE

Figure 24 shows the structure of three of the

herds found in the Gal Oya area, classified according to size class, and Figure 25 the total for these

three. There is definite variability between the three

groups as to the proportions of the various size

classes in each of the herds, but on the average

there is a relatively high proportion of adult

animals, i.e., females of size class 6 or larger and

males of size class 8 and 9. These size classes, which

are all that can be determined in the field, are not

indicators of age classes (p. 10). Thus, size class

1 contains infants which are still suckling and are

probably less than one year of age, whereas size

class 4, for example, contains individuals which

are probably between 3 and 5 years of age, and

size class 5, individuals between 5 and 7 years old

for males and 5 to 10 years old for females.

It is possible to treat these data in two ways.

The first would be to rearrange the size classes into

approximate age classes according to the data

presented earlier (p. 10). This would then require

combining the first four size classes as representing

ages 0 to 5 years and size classes 5 and 6 for females

and class 5 for males to give the next 5-year interval.

Beyond this point, however, such rearrangement

of the data to provide a 5-year interval would require the splitting of size classes as the size classes

7 through 9 include animals of age classes of more

than 5 years. Using this method we can see that

for this sample of the total population of 181 individuals, 45 would fall between the ages of 0 and

5 years and approximately 25 would be between

5 and 10 years.

A more useful method is to compare the numbers

of adults, juveniles, and infants. Figure 26 shows

the results of making these divisions. In each herd,

as well as in each of the total populations, the

number of adults is always greater than the number

of juveniles which in turn is always greater than

the number of infants, although the total of juvenile

and infant animals may be greater than the total

number of adults. For most groups, however, the

ratio of adults to young is approximately 1:1.

As far as can be determined, the sex ratios among

infant and juvenile animals are approximately 1:1.

The sex ratios of adults, however, vary considerably.

Table 4 shows the sex ratios of adults from known

areas: thus, for example, the Hatpata herd contains

33 adult females whereas 14 adult males are known

to be resident in the area encompassed by the range

of the herd. The ratio then is 39 males to 100

females. Similarly the ratios for the other sectors of

the study area are for the western savanna area 20

to 25,males per 100 females; for the Amparai area

50 males per 100 females; and for Lahugala 40

males per 100 females. The sex ratios of juveniles

as mentioned earlier are approximately equal but

there is a relative scarcity of subadult males. It

would thus appear that the difference in sex ratios

observed among adults might be caused either by

a high mortality among subadult males or by

TABLE 4.—Sex ratios of adult elephants in four

regions

Region

Hatpata

Western Sector

Amparai

Lahugala

Adult

$

Adult

9

Ratio

3:100 $

14

6

11

20

S3

25-30

22

50

39

20-25

50

40
38

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

1 2 3 4 5 6 7 8&9

C

-25 .

<D

£ 20

15

10"

Amparai

airport

Dec.,1968

2 5 i

20- Hatpata

Jan.,1969

1 2 3 4 5 6 7 8&9

25

20-

15

10

1 2 3 4 5 6 7 8&9

0

Talawa

Feb.-Apr.,1968

1 2 3 4 5 6 7 8&9

Size class

FIGURE 24.—Size class distribution for three herds in the Gal Oya population. Black —adult males.
NUMBER 125

70 -i

60H

39

—

§50-

^40 -

Gal Oya

Total of 3 herds

>

£

O 30-

L.

r20-

Z

10-

1 2 3 4 5 6 7 8&9

Size class

FIGURE 25.—Size class distribution of the elephant population

in the Gal Oya region. Black —males.

dispersion of animals in this age class. There is

some evidence for a high degree of dispersion

among subadult males (p. 85), but the lack of

observations of these animals in the areas covered

would indicate a higher mortality of animals in

this age class. It would appear likely that a young

male recently separated from the herd would

be vulnerable not only to aggressive attack by other

males through whose home ranges he was traveling

but also to accidents and to being shot by cultivators. Unfortunately, we have very little data to

support these hypotheses.

The data from Lahugala (Figure 27) show a

similar trend to that observed in Gal Oya. The

relative proportions of adults, juveniles, and infants

are approximately the same as the totals observed

in Gal Oya, although the proportions of infants

would appear to be somewhat higher. The sex

ratio of adults at Lahugala is approximately the

same as that for the Gal Oya area. Figure 28 shows

the breakdown of data obtained in 1967 in Ruhunu

National Park (Blocks 1 and 2) and again the

trend is relatively close to those of the preceding

two areas except that the relative proportion of

Jun. 68

Hatpata

Jan. 69

Amparai

Talawa

6 7

Lahugala

6 8

J

20 40

No. Individuals

6 0

FIGURE 26.—Histogram showing frequencies of the three major

age-groups (adult, juvenile, infant) in the elephant populations of eastern Ceylon. Shaded areas=adult males.

infants is much lower while the proportion of adults

and juveniles remain approximately the same as

do the sex ratios of adults.

Eisenberg and Lockhart (1972) report a similar

age structure and sex ratio but comparable data

from mainland Asia are not available.

The only data of a comparable nature from

studies of the African elephant are those of Laws

(1969b). He (1969b: 520-521) gives age and sex

compositions for four populations within Tsavo

National Park, Kenya, and for three other areas.

Although the sex ratios vary between these populations there is a consistent pattern of a lower number

of males than females above age 30, although the

sex ratios of the age group 20—30 are near equality.

Whether this difference is due to an actual difference in numbers or to male groups not counted in

the surveys for one reason or another is not explained by the author.
40

35-

30-

2 5-

j_2On

E

215-

1 0 -

5-

0 -

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Lahugala

Nov.,1967 Nov.,1968

1 2 3 4 5 6 7 8&9 1 2 3 4 5 6 7 8&9

Size Class

FIGURE 27.—Size class distribution of the Lahugala elephant population as determined in 1967

and 1968.

While the age composition data presented by

Laws (1969b) for Murchison Falls National Park

and the Budongo Central Forest Reserve (both in

Uganda) are similar to those recorded in Gal Oya,

the data from Tsavo National Park show a much

higher proportion of infants and juveniles. Further

discussion of these data relative to my own will be

made in the following section as they present a

valuable comparison of recruitment rates.

NATALITY

Table 5 shows the birth rates and birth intervals

for three segments of the Gal Oya population

during 1968 and for the Lahugala population in

1967 and 1968. The percentage of females in the

adult population (p. 37) is relatively constant.

The low figure from Lahugala in 1967 reflects only

a part of the total female population sampled

during that year (one large herd was not censused

until 1968). The numbers of infants include those

judged to be one year old or less (class 1) and

those judged to be between one and two years old

(class 2). Thus the percentage of adult females

who gave birth to infants during the year preceding

the actual census is only a crude estimate.

The percentages of females with young are quite

variable. The factors which may be involved in

causing these differences include: (1) annual seasonality in births, (2) synchronization at an

interval longer than one year (thus producing a

high number one year and low numbers for the
NUMBER 125 41

301

in

a

•o

>

C

(D

n

E

=5

2CH

1 0 -

Yala

June-August, 1967

1&2 4 5 6

Size class

7 8&9

FIGURE 28.—Size class distribution of the Ruhunu National

Park (Yala) elephant population in 1967.

next one or two years), (3) differences in mortality

among infants, and (4) differences in mean-birth

intervals between populations. Age of females at

puberty can be eliminated as a potential factor

since my definition of an adult was based on observable development, especially of the mammae, not

strictly on size. Exact data which might point to

one of these factors or a combination of two or

more are unfortunately not available. This is in

part due to the small sample size (compared to

samples available to such workers as Laws (1969a)

and in part to the duration of the study, two complete annual cycles. It is not possible to state

whether there is any seasonality of births or of

mating, as observed in Loxodonta by Hanks (1969)

and others. Newborn infants were observed on only

two occasions, November 1968 and January 1969.

Copulation was observed only in November 1967.

Interactions between animals from which it was

inferred that one or more females might be in

estrus were observed in March 1968, June 1968,

October 1968, and in January 1969. With such

sparse data I can only conclude, as did Eisenberg

and Lockhart (1972) for Wilpattu, that there is

no evidence for seasonality.

The numbers of infants in size class 2 would

indicate that there is a distinct possibility for longer

term synchronization (shown by Laws (1969a) for

Loxodonta) or for differences in infant mortality.

For example the Hatpata subpopulation and the

Lahugala population show approximately equal

numbers of older infants and younger ones, while

the Amparai subpopulation had a larger number

of younger infants, and the Talawa (western sector

of the Gal Oya National Park) subpopulation, a

larger number of infants one year or more. While

these data indicate that one or the other factor may

TABLE 5.—Estimates of birth rates and birth intervals

Gal

Hatpata

(June)

47

S3

70.S

4

4

12

8»

5

#

4

2.5

Oya 1968

Amparai

(Dec.)

33

22

66.7

'6

3

27

4«

2Jb*

2

_

Talawa

(June)

32

26

81.3

1

4

4

25

16

12

8

Lahugala

1967

Nov.

48

28

583

5

3

18

5

4

25

_

1968

Nov.

68

48

'70.6

11

10

25

4«

2.5«

2

_

Total adults

Total adult females

% females (2)/(1) x 100%

Total infants <1 year (class 1)

Total infants 1-2 years (class 2)

Infants per 100 females

Calculated birth intervals (to nearest 0.5 year)

assuming:

no mortality

33% mortality

50% mortality

67% mortality

•Most reliable data.
42 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

be involved they do not provide any means of

deciding which one.

In order to separate these two factors it would

be necessary to know the absolute rate of mortality

for each cohort of infants. In order to obtain such

data it would be necessary either to census each

population over a number of years or to follow

all of the populations at short intervals throughout

the two years of the study. In practice neither was

possible for all of the populations. Detailed counts

of the Hatpata and Amparai populations were

made at short intervals and no infants were

reported missing for the groups studied during

1968 and 1969. This would tend to indicate that

for these two groups at least infant mortality is

either very low or occurs during the first few weeks

of life and that for the Amparai group at least

there appears to be some synchronization on a

cycle of at least two years. The Lahugala data also

indicate that infant mortality is low, but there

is either no apparent long-term synchrony or a longterm trend, only part of whose cycle was followed.

The final factor that can be examined is that of

birth interval. As any calculation of birth intervals

depends upon the assumptions about mortality and

synchronization, it is reduced virtually to the point

of speculation. Speculation, however, is worth

making if only to emphasize the need for longer

term studies. Based on the assumptions made above

I have calculated (Table 5) a set of possible birth

intervals. For the three populations with the best

data available the most likely estimates are marked

with an asterisk. If these assumptions are correct,

it would appear that the Amparai and Lahugala

groups are similar and have a relatively short meanbirth interval, while the Hatpata group has a

longer one. The Talawa group presents an interesting possibility in that it must have either a very

high infant mortality, a very long mean birth

interval, a strong synchronization, or a combination

.of two or more. Whichever factor is in operation

here, it is obvious that this subpopulation has a

very much lower recruitment rate than any of the

others.

Buechner, et al. (1963) and Buss and Savidge

(1966) report data on the recruitment rates of

elephants in Murchison Falls National Park,

Uganda, from 1957 to 1964. They report average

frequencies of infants around 8-9 percent of the

total population. Assuming an adult sex ratio of

1:1 this would correspond roughly to 15—20 percent

of the female population, a figure comparable to my

1967 data from Hatpata and Lahugala. Laws'

(1969b) data from Murchison Falls and Budongo

are approximately equivalent but data from Tsavo

indicate a higher percentage of infants. Laws

(1969b) concludes that there has been a steady

decline in recruitment in the Uganda populations, a trend first noticed by Buss and Savidge

(1966), but that some portions of the Tsavo population have continued to increase the recruitment

rate. This latter trend Laws attributes mostly to

the suppression of hunting. He also concludes that

there is some self-regulatory cycle in the recruitment rates which account for his observations of

unequal recruitment between successive cohorts.

Like Buss and Savidge (1966), he (Laws, 1969b)

concludes that this regulatory mechanism is density

dependent but that it may well be mediated by the

effects that the elephants have on their environment.

How these conclusions, based on many years of

observations of large populations in East Africa,

relate to the phenomena occurring in the much

smaller populations of Ceylon is, at the moment,

not apparent. The densities of the various subpppulations I studied (see pp. 96—97) are roughly equivalent. All groups are subject to at least some

harassment and shooting by man. The most

parsimonious conclusion at this time would be that

with such small sample sizes, any one factor, operating over even a short period of time, might produce

an apparently large effect on the recruitment of

any of these populations. Thus the only way it will

be possible to state with any precision what the

actual status of recruitment is in these populations

is to collect data over a period long enough to

eliminate such short-term vagaries.

MORTALITY

Data on mortality are also extremely sparse (Table

6). The records from October 1966 to September

1967 were provided by the Game Ranger, Mr. Bevis

Ekanayake, and indicate seven animals known to

have died in his area during that period. I examined a further seven which died between September 1967 and November 1968. Of the 14 from

the Gal Oya, only one was an infant, the rest were
NUMBER 125 43

adults. These 14 deaths throughout a 2-year period

can be taken as an absolute minimum estimate of

the total mortality in the area. It is extremely

likely that the mortality is much higher than this

but as elephants that die away from cultivated

areas are located only by chance, it is impossible

to make an estimate of the upper limit for the rate

of mortality. The structure of various size classes

(Figure 25) would tend to indicate that there is a

certain amount of mortality in the first 10 years of

life, if one can assume that the birth rate is relatively even each year. If such an assumption concerning the birth rate can be made, it would appear

that the mortality during these first 10 years of life

might be as high as 2 to 3 individuals per year for

the entire Gal Oya population. The causes of death

are various but the majority in this area are the

result of gunshot injuries (Table 6).

TABLE 6.—Known mortality of elephants in the

Gal Oya region 1966-1969

Date

Oct. 66

-Sept. 67*

Sept. 67

Nov. 67

Aug. 68

Aug. 68

Sept. 68

Oct. 68

Oct. 68

Location

Gal Oya range

Nilgala

Paragahakelle

Inginiyagala

Mahakandiya

Namal Oya

Kossapola

Ambalam Oya

Sex 1 Age

1 ?

1 ?

1 ?

4 ?

$ A

$ A

9 A

9 A

$ I

9 A

$ A

Cause of death

Killed in self-defense

Gunshot injuries

"Apparently natural

causes"

Unknown

Shot and killed by

cultivator

Shot and killed by

cultivator

Septic gunshot wound

on leg

Multiple gunshot

wounds

Noosed—apparently

died after capture

from lack of water

and/or food.

Unknown

Multiple gunshot

wounds

•Data provided by Mr. B. Ekanayake, Game Ranger,

Inginiyagala.

? = Sex and age not recorded.

There is definite evidence of sex-specific differences in mortality as reflected in the low adult sex

ratio. This has certain consequences for the social

organization of the elephant (pp. 81-85). Laws

(1969b) presents a survivorship curve for the Tsavo

population in East Africa. He describes a fairly

high mortality rate over the first 3 years followed by

a fairly low rate until age 30 for males and 50 for

females. The sex difference in mortality in older

animals is similar to that inferred for the Ceylon

populations. A lack of comparable data in the

form of elephant carcasses makes any further comparison with Laws' data impossible.

Behavior Patterns

LOCOMOTION

The elephant is capable of moving either extremely

slowly or quite rapidly. At whatever speed it is

traveling, however, the gait is a modification of one

basic gait, the rack or pace (Muybridge, 1899). In

this gait, the sequence of movement of the legs is

left hind, left fore; right hind, right fore. In a

single stride at a slow walk, the left hind foot is

raised as the right forefoot, ending the previous

stride, is being placed on the ground. As the left

hind foot is moved forward, the other three feet

are firmly on the ground. At the same time as the

left hind foot is being placed on the ground, the

left forefoot is lifted. As the left forefoot moves

forward, the remaining three feet again are on the

ground. With the placement of the left forefoot on

the ground at the end of its forward swing, the

right hind foot is raised and the pattern is repeated

on the other side completing the stride. In this

way, three feet are on the ground for most of the

stride; one foot being off the ground for a short

period and two feet off the ground only for an

extremely short period.

At a faster walk the forefoot is raised at the

same time as the ipsilateral hind foot is being

brought forward so that two feet only are in contact

with the ground for a longer period of time. During

the slow walk, the body and the head of the animal

remain relatively stable, but during a fast walk

there is a marked rolling motion of the body as

the center of gravity shifts from one side to the

other, accompanied by a definite bobbing of the

head. This lateral motion of the body and bobbing

of the head increase in amplitude as the speed of

movement increases, and are extremely marked in

an animal running at a fast pace.

If the animal is feeding at the same time as it is

moving, the slow walk is generally used; an animal

moving without feeding generally travels at a fast

walk. In both the slow walk and the fast walk, the

position of the trunk and tail are quite variable.
44 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Infant and juvenile animals quite frequently move

at faster speeds than the walk, i.e., when playing,

chasing each other, etc., and at these times the

trunk is generally held up and the tail is also

arched upward. Fast movement by adult animals

was observed only in cases of flight and attack. In

these instances the tail is held arched upward and

the position of the trunk varies, being held upward

in the sigmoid pattern during flight but curled

ventrally under the chin during attack. When

running both adults and juveniles seem to show

more arching of the back than is observed during

slower locomotion.

Throughout many parts of the Gal Oya area

the terrain is quite steep and rough with many

large boulders. In general the elephants tend to

move about in such areas along well-defined trails

where it is possible for them to walk at a normal

pace with a normal gait. Elephants have, however,

been observed to climb relatively steep rocky areas

and, in such instances, when ascending, they will

occasionally make use of the elbows of the forelegs;

and when descending will drop to the knees of

the hind legs. In this manner, they are, when necessary, able to negotiate areas which at first sight

would appear to be impossible for an animal of

such large size and weight.

Elephants are quite capable of swimming and

do so readily. On 7 April 1967, for example, three

females were observed feeding on an island in the

Senanayake Samudra at 1615 hours. At 1805 the

same three were feeding on a smaller island about

50 m away from the island on which they were

previously observed. As we approached in a boat,

the three reacted to our presence when we were

100 m distant, moved to the side of the island

closest to the first island, entered the water and

swam across to the larger island where they entered

the forest and passed out of sight. They covered

the distance of approximately 50 m between the two

islands in about 3 minutes. During this short swim

we were able to maneuver our boat quite close to

the animals (15-20 m) and it was possible to see

that the bodies of the animals were moving with

approximately the same rolling motion as would

be present at a fast walk or run. Throughout the

swim most of the animals' bodies remained subberged; only the tops of the heads and trunk tips

being above the water.

On 9 October 1967, a herd of 28 elephants, observed by myself and Dr. Nettasinghe, were feeding

on the point of land separating the Sellaka Oya

arm of the Senanayake Samudra from the Kossapola arm. At 1645 hours the herd divided into

two sections; a group of eleven moving off to the

southeast, the remainder moving eastward toward

the edge of the water. By 1658 all of the animals

under observation had disappeared from sight behind an island which lay between our position and

the elephants. At 1747 hours, however, one elephant appeared on land from behind the island

and entered the water. At 1759 six animals

emerged from the water on the near side of the

arm, that is to say, the Hatpata side and by 1802

hours 14 animals had emerged from the water.

Under the conditions of low water at that time,

the distance covered by the animals in the water

was a minimum of 200-250 m. Assuming that the

rest of the herd entered the water at approximately

the same time as the one that was observed to enter the water, this swim took a minimum of 12

minutes. It would, however, be more reasonable

to assume that the animal observed entering the

water was the last one to do so and that the length

of time necessary for the swim was probably more

in the order of 20 minutes or more.

Swimming is apparently common with the Asiatic elephant and is very well described by Sanderson (1878). There has, however, been considerable debate in the literature concerning the swimming ability of Loxodonta. Verheyen (1954) and

Bourliere and Verschuren (1960) state that it cannot, but Dekeyser (1955) and Sikes (1971) have

produced sufficient evidence to correct this misconception.

RESTING AND SLEEPING

Adult elephants in the wild generally rest in a

standing position. Under field conditions, it is

impossible to determine whether the animals are

actually asleep during these rest periods, so for

purposes of this discussion, they will be considered

as resting. An adult elephant may rest either standing free or touching some object such as a rock

or tree. If the animal is standing free, it generally

spends most of the rest period standing on all four

legs with the tip of the trunk resting on the ground.

Occasionally, however, one leg will be lifted slightly
NUMBER 125 45

from the ground, and on two occasions animals

were observed to alternate between lifting a hind

leg and a foreleg. Occasionally these periods of

resting may be accompanied by a slight bobbing of

the head and body. The bobbing movement includes a lateral component and is very similar to

the pattern commonly called "weaving" by keepers

of captive animals. The rhythmic movements are

not so pronounced as those shown by captives, and

the swinging of the trunk which so frequently accompanies weaving in captives is not shown by

wild elephants. When resting in contact with an

object such as tree or rock, the elephant may lean

against this object with its back or hind quarters

or it may extend the trunk or even the chin over

a low branch or over the rock.

In sitting or lying down, the elephant first goes

down on the hind quarters, the forelegs being

stiffly extended. The forelegs are then flexed to

bring the animal to rest on its belly and elbows

after which the animal then lies down onto one

side. When lying asleep, the legs are generally extended and the trunk may or may not be curled

inward as described by Benedict (1936) and Kurt

(1960). Infant and small juvenile elephants frequently lie down to sleep for short periods but, in

large juveniles and adults, lying down was infrequently observed. One male in Ruhunu National

Park was observed, however, to lie down for periods

varying between 20 and 75 minutes between 30

June and 8 July 1967. He rested each day in the

same place on the large plain surrounding Buttuwa

Lagoon. These rest periods took place in the midafternoon between 1400 hours and 1700 hours, and

resting occurred always within a mud wallow which

was used both by the elephants and by water buffalo. Adults were also observed on a few occasions

to sit and rest on the elbows or even lie down completely while bathing and drinking in tanks. In

these instances, however, the period of actual lying

down was very short, usually less than 5 minutes.

Juveniles and infants regularly lie down in shallow

water when bathing.

FEEDING

In feeding the elephant uses primarily the trunk,

especially the terminal portion, although there may

be varying amounts of usage of the feet and mouth

in reducing foodstuffs to a suitable size. The patterns which the elephants show vary depending

upon the type of plant being fed upon at the

moment.

Grasses

The simplest pattern is that shown when elephants

are feeding on grasses and other herbaceous matter of a length between 5 and 75 centimeters. When

feeding on herbs of this length, the terminal 25 to

35 centimeters of the trunk (the "hand") is used

to grasp a number of stems, curling around them.

The stems are then pulled, generally vertically but

with a slight lateral component, and put directly

into the mouth. With slightly longer grasses such

as those which grow in wet areas, the grasping and

pulling is followed by a swinging motion in which

the grass is held in the "hand" of the trunk, and

the trunk is held slightly forward and swung from

side to side several times. This pattern was shown

mostly by animals feeding in marshy or swampy

areas. After anywhere from three to ten such

swings, the grass is then placed into the mouth.

Roots may be bitten off and expelled, although this

does not necessarily occur.

When feeding on grasses which are shorter than

about 5—7 centimeters, the elephant does not seem

to be able to grasp and pull with the trunk alone.

In feeding on this type of material, the first action

is a forward kick with forefoot which acts to scrape

the surface of the ground, generally to a depth of

no more than 5 to 10 millimeters. This scarifying

action removes the grasses, including a certain percentage of the rhizomes, from the soil, forming a

loose pile. After an area of about 0.1 square meters

has been cleared in this manner, the end of the

trunk is used to sweep and gather together this

loose pile of grass. In this sweeping motion, the

"hand" of the trunk is laid flat on the ground and

curled ventrally as it is dragged across the ground.

This clump of grass so formed is then picked up

or gathered in the "hand" and may be either

bounced on the ground several times or grasped

more firmly and rubbed against one of the forelegs

before being inserted into the mouth.

Shrubs

When feeding on twigs and small branches, the

end of the trunk is used to grasp a twig, which is
46 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

then pulled with a short, rapid, jerking motion

that generally is sufficient to remove it from the

larger branch. If larger branches are removed from

a tree or shrub, they may occasionally be twisted

in order to remove them. Usually the elephant

removes from a shrub or tree a small twig, which

is then placed directly into the mouth. If, however, a larger branch is removed, it is dropped and

may be held with one forefoot while smaller twigs

are removed from it with the trunk. Elephants

occasionally feed on the bark of certain tree species, such as Feronia. When feeding on bark, a

large branch is broken off from the tree and held

on the ground with one foot while smaller portions

of the branch are broken off using the trunk. These

smaller sections are then grasped in the trunk,

inserted in the mouth, and, by a turning motion

of the trunk tip, are turned either between the

molars or against a tush which serves to strip the

bark from the branch. It is interesting to note

that this stripping action involves rotation of the

branch against the parallel transverse ridges of the

molars. Richard Van Gelder (pers. comm.) of the

American Museum of Natural History has informed

me that Loxodonta uses a lateral pulling motion

rather than the rotation of Elephas, apparently

pulling the bark over the anteriorly projecting

ridges on the lophs of the teeth.

When feeding from trees or bushes, it is usual

for the elephant to remove either small twigs or

one or more large branches, leaving the main stem

of the tree untouched. Occasionally, however, trees

are pushed over or perhaps pulled over. No instance of this type of behavior was actually observed, so it is not possible to say which of the

two techniques is used. According to Hendricks

(1971) the African elephant generally pushes the

tree over using the forehead.

When feeding on certain types of very low growing shrubs, such as Acacia eburnea, which have

very long spines projecting horizontally from the

stem, the elephant first curls the trunk around the

stem and, with a rapid upward motion of this

curled trunk tip, breaks all of the spines without

actually removing them and without removing any

of the leaves. These spines can often be recovered,

entire, from the feces (p. 93). After this stripping

action has been performed, the stem is then grasped

and jerked free from the soil. If the jerking motion

fails to free the stem, then the stem will be grasped

in the trunk and then kicked closer to the ground

by one forefoot, thus disloding it. The stem is then

placed whole into the mouth.

One interesting feature of feeding behavior in

Elephas is the use of the forefeet in holding

branches and twigs while removing smaller portions. According to Sikes (1971:76—78) this pattern

is not displayed by Loxodonta. Rather, Loxodonta

makes extensive use of the tusks along with the

trunk to remove small portions of branches. I was

unfortunately not able to obtain sufficient observations on feeding by tuskers in Ceylon to determine

whether they followed the pattern shown by Loxodonta or that of tuskless Elephas. My few observations from two individuals would tend to indicate

the latter is the case.

DRINKING AND BATHING

Although drinking and bathing are not necessarily

related as functional categories of behavior, they

are included together in this discussion as they

often tend to occur simultaneously. When drinking, the elephant sucks water into the trunk then

raises the trunk inserting the trunk tip into the

mouth, accompanied by a slight raising of the head

as shown in Figure 29. This allows the water to

drain into the throat. Young elephants generally

tend to drink in the same manner as adults, although on a few occasions juveniles, estimated to

be about 5 years old, were observed to immerse

themselves up to the level of the mouth and drink

directly without any involvement of the trunk.

When drinking and bathing occur during the same

visit to water, drinking generally precedes bathing.

Elephants may drink from small bodies of water,

such as pools in the ground or in crevices in rocks,

or larger more permanent water sources such as

streams, rivers, and man-made reservoirs. The elephant stands either at the edge of the water or in

shallow water. Although surface water is generally

used for drinking, there are times during extreme

drought when surface water is not available in

many areas. At such times elephants frequently

tend to concentrate around particular sections of

streams which have a sandy bed. The elephants

then dig holes in the sand in order to reach the

sub-surface water which remains in such pockets.

The holes in the sand are excavated by a forward
NUMBER 125 47

FIGURE 29.—Photograph of male elephant drinking, showing typical posture of head and trunk.

kicking movement of the forefoot which results in

the formation of a hole with one sloping side and

one steep side, as figured by Tennent (1867). The

shape of the hole is a result of the means of digging

rather than any attempt by the elephant to prevent

caving in of the walls as postulated by Tennent.

Elephants appear to have traditional drinking

spots, both water holes and sandy stream beds

(p. 85). When bathing an elephant sucks water

into the trunk in the same manner as when drinking and then sprays the water onto the body. In

spraying the water, the trunk is swung forward

slightly, then swung backward either laterally, ventral ly, or vertically over the top of the head, releasing the water in a spray over the body. There

does not appear to be any general pattern or order

of spraying the various parts of the body. Some

individuals appear to spray the sides and ventrum

and dorsum in rotation while others will spray first

one side and then the other, then the belly, etc.

Young elephants generally tend to bathe by immersing themselves totally rather than by spraying,

frequently lying down and rolling in the shallower

portions of waterholes and tanks. Occasionally an

adult will be observed to lie down and roll in the

water, although the occurrence of this is infrequent.

Tennent (1867) described elephants apparently

regurgitating water and spraying it via the trunk

onto the body. No instance was observed among

wild elephants in Ceylon where water was sprayed

other than when bathing at a water hole. At a

government khedda conducted near Kakankote,

Mysore, India, in January 1968, a number of elephants confined without water in the roping stockade were seen to perform a series of actions which

appeared like those described by Tennent. Sev-
48 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

eral animals, standing in a group in the center of

the stockade were seen repeatedly placing the trunk

tip into the mouth. Following removal of the trunk

tip from the mouth they would swing the trunk in

the typical manner of an animal bathing, releasing

a spray of some liquid over the head and back.

Whether this action involves regurgitation as

suggested by Tennent, is impossible to say from

these observations. Other alternatives might be

salivation or condensation of water in the trunk.

Bannikov, et al. (1961:16) have suggested that the

expanded nose of the Saiga (Saiga tatarica) may

serve to condense water vapor. A similar mechanism might well occur in the elephant. In arid

areas this would undoubtedly act to conserve water

from exhaled air. Under conditions of extreme

heat stress and lack of free water this condensate

could then be used to help promote heat loss by

spraying it on the body.

MUD-AND-DUST BATHING AND RUBBING

Besides bathing with water, elephants also frequently cover the body with mud or dry soil. Bathing with mud may occasionally take the form of

wallowing or lying down and rolling in a mud

hole. This pattern, however, was observed infrequently and only with solitary males, never with

females or young. The more usual pattern is for

the animal to collect mud with the trunk tip by

curling the terminal portion of the trunk around

a bolus of mud and then throwing it onto the body

dorsally, ventrally, and laterally. A similar manner

of collecting by curling up the trunk tip is used

when throwing loose soil or dirt onto the body.

In the latter case, the soil is generally loosened

prior to collecting by the same kicking motion of

the forefeet which is used in loosening short grasses.

Covering of the body with mud generally appears

to occur independently of bathing in water (either

as an alternative to bathing in water or as a totally

independent phenomenon). Covering the body

with soil on the other hand appears to occur most

frequently after bathing in water although frequently elephants are observed to cover themselves

with dirt without having bathed immediately prior

to this.

After bathing with either water, mud, or soil,

elephants frequently rub the body against some object such as a tree or rock. A typical sequence is

for an animal to leave the water hole after bathing, stand for a few minutes on the bank, cover

the body with dirt, then move toward some tree

in the general neighborhood of the water hole and

proceed to rub against it. This pattern was observed frequently among males at Lahugala Tank

where animals upon leaving the tank would generally dust bathe and rub against a tree before

entering the forest.

In rubbing the animal generally approaches the

tree frontally and commences to rub the forehead

and trunk base against the stem of the tree, then

rubbing the sides of the head and the neck, followed by rubbing of the sides of the body and

lastly the rump and perineal region. If the tree

should have a low branch or if a rock is used

rather than a tree, the elephant will frequently

also rub the chin. Certain trees appear to be used

regularly and such trees as that shown in Figure

30 are obviously used extensively. The lower portions of these trees become covered with a layer of

mud and the bark often tends to become smooth.

Besides rubbing the skin against the tree, an elephant will often at the same time rub the tusks or

tushes against the bark often producing the elongated gashes in the bark (Figure 30).

Occasionally trees are found with gash marks

from tusks or tushes in the bark without any evidence of rubbing. Eisenberg and Lockhart (1972)

have postulated that this may be a form of marking,

particularly if the tree so marked were to have an

odorous sap. Within the Gal Oya area, the two

species of trees most frequently marked with gashes

from tusks were Pterocarpus marsupium and Careya arborea, both of which have a sap that has a

slight odor and for Pterocarpus marsupium a faint

pink coloration. Regardless of the odor of the sap

exuding from the wound in the tree, the odor of

elephant is always present at such sites. How long

the odor of elephant remains at such a rubbing

site is unknown but on the 10th of September 1968

we followed the path of an elephant, apparently

solitary, moving northward 2 miles south of the

Gal Oya near Nilgala. This elephant had broken

down 29 stems of Terminalia chebula, all within

the 15-30 centimeters dbh class, and marked with

the tusks a further 18 trees of the same size and

species. There was, incidentally, no evidence of

feeding from any of these trees. We guessed that
NUMBER 125 49

FIGURE 30.—Frequently used rubbing tree showing raudcovered area and gash-marks caused by tusks.

the probable cause of this activity was either displacement or redirected aggression after some disturbance (possibly by loggers who were working

nearby) along a nearby road.

The condition of the leaves on the trees which

had been killed and the condition of the pile of

dung found along the trail indicated that this activity had occurred not less than one and not more

than two days previously. The odor of elephant

was distinctly noticeable on all of the affected trees.

Besides rubbing against objects, the elephant will

also use its own trunk and tail to rub various parts

of the body. The trunk tip is frequently curled

and used to rub the region around the eyes and

the region of the neck, throat, chin, and behind

the ears. The tail is used to rub the perineal region and between the legs in the region of the external genitalia. Also one foot may be used to rub

the contralateral foot. Although captive zoo elephants have been observed by the author to pick

up objects such as sticks or twigs in the trunk and

use them to rub the body, no instance of this was

observed during field observations in the Gal Oya

area. In all cases the various organs of the body

were used directly or the body was rubbed against

some stationary object.

DEFECATION AND URINATION

During both defecation and urination, the animal

generally stands in a normal resting posture, although young animals were observed to squat occasionally upon urination and females often tend

to spread the hind legs apart somewhat. This

spreading of the hind legs was observed in a male

only once. During defecation the tail is usually

raised to a horizontal position. When a male urinates, the penis is partially erected to the point

that the glans is directed backwards. In the female

the clitoris may also be erected somewhat at urination. Urination may occur without defecation but

a defecation is almost invariably followed by urination.

Elephants may frequently urinate and defecate

when moving, leaving the feces and urine on the

trail along which they have been moving. No evidence was found for any site specificity in either

urinating or defecating but this does not in any

way prove that the urine and feces are of no value

to the elephant as a chemical signal. Whenever an
50 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

animal approaches reasonably fresh urine or feces

deposited by another elephant, it generally extends

the trunk tip towards it. On several occasions

males were observed, after extending the trunk

towards the urine or feces of another elephant, to

insert the trunk tip into the mouth. This action

has been described by Eisenberg, McKay, and Jainudeen (1971) in the context of sexual behavior

and it was concluded that this is probably, in part,

homologous to the flehmen response of many other

mammals.

Observations show that elephants generally defecate on the average of every one to I14 hours or

approximately 18 to 20 times per day. From 4 to

7 boluses are passed at one time, the average being

5. For an adult, each bolus may weigh between 1

and 3 kilograms upon deposition. A sample of 20

boluses from freshly deposited feces contained

45—75 percent water by weight.

EXPLORATORY BEHAVIOR

Whenever elephants are moving and even when

standing still, the trunk is generally constantly in

motion. The trunk tip is frequently extended directly ahead of the animal and towards the ground

as an animal moves along. In this way the elephant

appears to be sampling its olfactory environment as

it walks. Whenever the elephant encounters such

objects as the feces of another elephant or even of

other animals, or sign of man such as footprints,

the trunk will be extended towards such objects.

At frequent intervals during locomotion the

animal may stop and the trunk will be raised in a

sigmoid curve, extended outward away from the

animal and moved from side to side. This action

appears to be analogous to the pattern of raising

the head with a lateral movement shown by many

other ungulates: in other words, a means of testing

for potential scent in the wind. This pattern is

frequently accompanied by an extension of the

ears. When the elephant has apparently picked up

some indication of the presence of man or some

other species in the vicinity, the responses may include these latter components of the extension of

the trunk and of the ears and may also include

rotation of the entire body axis, as well as a variety

of other responses. For further discussion of the

responses of elephants to other animals including

man see Muckenhirn and McKay (n.d.).

Small objects that the elephant encounters are

frequently picked up with the end of the trunk

and, especially with plant material that can be

considered potential food, placed into the mouth

before being discarded.

FLAPPING OF THE EARS

Based upon the observations of Kuhme (1963)

made upon captive Loxodonta, it was postulated

that elephants might be able to thermoregulate by

means of inducing a flow of air over the ears.

Frade (1955:757-758) has described the large veins

and arteries connected by an extensive capillary

bed for the ear pinna of Loxodonta africana. Although the pinna of Elephas is comparatively

smaller with relation to body size, there is a comparably large supply of blood vessels. Examination

of two recently dead elephants from Ceylon showed

that th.e blood vessels of the ear lie particularly

close to the skin on the inner or posterior surface

of the pinna, the skin of the anterior surface being

somewhat thicker.

Between 19-23 July 1967 and 12-19 December,

observations were made on the ear-flapping rates

of seven adult males and three subadult males at

Lahugala Tank. The animals were observed

through a telescope with a 25 magnification ocular

lens and the number of flaps in a particular bout

was recorded. An interval is measured from the

last flap of a bout to the onset of the first flap of

the next bout. The number of flaps in the bouts

following the timed interval were subsequently recorded. Intervals were timed to the nearest 0.1 second using a stop-watch with an accuracy of ±0.5

seconds. For each set of observations, 10 such combinations of bout-interval-bout were timed and the

averages computed. Such data were recorded under

varying conditions of overcast and wind velocity.

Throughout all of the observations, the animals

were feeding in the tank and were completely away

from any potential shade. Under such conditions

the concept of temperature in the shade is relatively meaningless and the relative amounts of

heat stress to which the elephant is subjected will

depend more on the amount of direct radiation

from the sun and on the cooling effect of the wind.

The data obtained are shown in Appendix 2 and

Figures 31 to 34. As shown by Figure 31, the

number of fans of the ear in a bout preceding the
NUMBER 125 51

measured interval approximately equaled the number in the bout immediately following that interval. Since this equation satisfies all observations,

the first bout only will be considered in the presentation of subsequent data.

Figure 32 shows the relationships of the mean

number of flaps per bout to the prevailing weather

condition. During overcast conditions, the number

of Haps per bout was greater in the absence of

wind than with a light wind for both adults and

subadults, although the difference was greater. Under sunny conditions, however, the number of flaps

per bout was greater under a strong wind than

under a light wind. As shown by Figure 33, the

average interval between bouts of flapping was

longer the higher the wind for both overcast and

sunny conditions. For the two sets of observations

where the wind velocity was classified as light

(Force 1 on the Beaufort Scale), the interval between bouts of flapping was slightly longer with

an overcast sky than with direct sunlight. Figure

34 shows a summary of the relationships between

the number of flaps in a bout, the duration of the

interval, and the varying weather conditions. As

10

c

"o

I/)

c

CO

L L

2 4 6

Fans in bout preceding

FIGURE 31.—Relationship between number of ear fans in bout

preceding and following measured interval.

shown earlier the interval between bouts increases

with increasing velocity of wind and decreases with

the increased direct sunlight for any particular

wind condition. The number of flaps in a bout,

however, decreases with an increase in wind velocity and to a certain extent decreases with increase

in direct sunlight, but this decrease occurs only

up to a certain point. At the same time, the factors

of increasing wind velocity and change in overcast

or direct sunlight influence a change on the interbout interval and it appears that as the inter-bout

interval gets longer, the number of flaps per bout

increases slightly. The reason for this change is

not apparent.

Under higher wind velocities the adult males

tend to keep the ears extended during intervals between bouts of flapping. The subadult males did

Overcast

. 1

Sun

SA

8 Wind speed 1 2-3

FIGURE 32.—Relationship of number of fans per bout to

different conditions of wind velocity and overcast. A=:adult;

SAz= subadult; wind speed on Beaufort scale; means and

ranges indicated on graph.
52 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

not show this pattern. This pattern would definitely allow greater flow of air over the ear surface.

Thus a decrease in cloud cover or a decrease in

wind velocity, both of which would tend to increase the stress of heat on an animal standing in

the open, tend to result in an increase in the intensity of flapping of the ears. This increase in

intensity could perhaps also be measured by timing the number of flaps per minute but the data

collected would tend to indicate that the number

of flaps in a bout and the intervals between bouts

may be varied independently. Buss and Estes

(1971, fig. 3) timed simple flapping rates (flaps/-

minute) for Loxodonta, which show a similar trend

in that at higher temperatures some of the elephants kept their ears extended rather than increasing the flapping rate.

Thus it would appear that flapping of the ears

Overcast

4)

120

80

10

Su n

SA SA

Wind speed 1

A SA

2-3

FIGURE 33.—Relationship of interval between bouts to varying

conditions of wind velocity and overcast. See Figure 32 for

meaning of symbols.

does serve a thermoregulatory function and is not

"merely a nervous reflex" as Benedict (1936:159)

believed. Ear flapping is not, however, the only

thermoregulatory device employed. Others include

bathing with water (evaporation), mud, or soil

(providing a layer of lighter colored dirt which

will reflect more light energy than the elephant's

black skin).

Another aspect that may be considered is ear

flapping as a social signal. Kuhme (1963) considered that the social status of the individual affected its (thermoregulatory) ear-flapping rate.

Since all but six observations of Elephas were made

of solitary individuals the social status factor appears minimal. It would be interesting, however,

to compare ear-flapping rates for animals at varying distances from their nearest neighbors, but unfortunately I did not record this information.

A further interesting observation is that on windy

days the pattern of holding the ears extended was

50

3 0

10

x fans per bout

FIGURE 34.—Relationships between number of fans per bout

and intervals between bouts. Solid lines—overcast conditions;

dashed lines = sunny conditions; arrows = increasing wind

speed; A —adult; SA = subadult.
NUMBER 125 53

displayed by adult males only, not by subadults.

One might hypothesize from this that young animals who have not yet established a dominance

order, or at least an "acquaintanceship" with all

other males (p. 84) might refrain from using this

pattern in thermoregulation as it might be "misinterpreted" as an aggressive gesture.

Short-term Activity Patterns

Several studies have been made of the activity patterns of both Loxodonta and Elephas in captivity.

Kuhme (1963) reports on the activity patterns and

cycles shown by three captive Loxodonta. He

found that the three animals were distracted to a

large degree by visitors to the zoo throughout the

day and that social interactions were predominant

around the early hours of the evening after visitors

had departed. He also described the resting patterns of these three individuals including recumbent sleep, which occurred for periods varying from

3 to 7 hours throughout the night.

Benedict (1936:64-73) reports on the activity

patterns of one particular female and several animals that belonged to circuses. He acknowledges

that some of the data may be biased by the fact

that these animals were used for performance and

therefore their activity routine was somewhat artificial. Assuming, however, that the basic patterns were normal and would probably be displayed

by animals in the wild, Benedict maintains that

the elephant in the wild is probably nocturnal and

that the diurnal cycle has been imposed upon the

elephant by its captors. He also notes the sleeping

patterns of animals in circuses, mentioning that

they are generally fed after the last performance of

the day at around 11.00 P.M. and, after feeding,

then lie down to sleep.

Kurt (1960) also studied captive Asiatic elephants in circuses, with particular attention to the

sleeping patterns. He found that the animals generally tended to lie down to sleep at one particular

time and inferred that there was some social facilitation involved.

In considering the above data it should be remembered that much if not all of the routine of a

captive animal is determined by its keepers rather

than by its own biological clock. This is especially

marked in relation to feeding where captive animals are generally presented with a relatively concentrated supply of food at one particular spot and

often at the same time each day.

THE DAILY ACTIVITY CYCLE

Times of Activity

Figure 35 summarizes the times of observation for

all animals observed in the Gal Oya National Park

region including the area of the Amparai Sanctuary. There are, however, two biases introduced

in the data. The first bias is the activity pattern

of the observer. In Ceylon dusk generally falls between 1815 hours and 1830 hours depending upon

the season, and dawn comes between 0545 and 0600

hours. On a few occasions it was possible to obtain

some data from animals that had been under

observation prior to sunset for a further one to two

hours but only a few attempts were made to locate

animals prior to dawn. As a result the decrease in

the number of observations after 1800 hours and

the scarcity of observations prior to 0600 hours does

not in any way reflect the activity of the elephants

themselves. The other bias is the ease of observing

elephants at a greater distance in open habitat, such

as grassland surrounding tanks and in the savanna

areas. As a result, the number of contacts made

with elephants was greater for these open habitats

than for forested areas. It is this bias which undoubtedly accounts for the relatively low frequency

of observations around the midday hours, which on

sunny days are the hottest hours, as the sun is very

close to the zenith throughout much of the year.

Keeping these biases in mind, there is an interesting trend with regard to the times of observed

activity of males and of female herds. The males

tend to show one peak of activity around 0800

hours followed by a decline around noon with a

second peak of activity between 1600 and 1700

hours. Female herds, on the other hand, tend to

show a later peak in the morning around 1000

hours with a second small peak between 1300 and

1400 hours followed by a very large peak between

1530 and 1800 hours. When these data are com

pared to Figure 36, which shows a similar analysis

for observations in Ruhunu National Park from

April to October 1967 and January and February

1968, it can be seen that the males in Ruhunu National Park show a pattern very similar to those

in Gal Oya National Park. Female herds in Ru-
54

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

0)

c

o

(TJ

>

ID

(/)

n

O

2 0

10

10

2 0

30

Males

05 08 11 14 17 20

Time

FIGURE 35.—Times and numbers of observations of elephants in the Cal Oya region.

hunu National Park, however, do not appear to

show the peak of activity in the morning hours or

early afternoon hours; instead the observations of

herds in Ruhunu National Park showed a peak

around the hours of dusk.

A possible reason for these differences in time of

activity of herds in the two areas might be found

in the patterns of drinking and bathing (Figure

37). The drinking and bathing times for males

tend to be distributed throughout the day for both

areas with no apparent peak times. For the herds,

however, this is not true. Herds in Gal Oya were

observed to come to water for drinking and/or

bathing between the hours of 1030 and 1630

whereas herds in the Ruhunu National Park were

observed drinking and bathing only after 1730

hours. Although not all observations of herds in

open areas included periods of drinking or bathing

in either area, most of the observations in Ruhunu

National Park were made in open areas which surrounded water holes frequently used by elephants.

It seems likely, therefore, that the bias towards the

early evening hours in Ruhunu National Park is

caused not so much by the inherent activity of the

elephants themselves but by disturbance from numerous tourist vehicles moving along the roads in

the park (and these roads generally pass by and

connect the open areas, especially in the coastal

strip). As the females inhabiting the area of Ruhunu National Park are much less tolerant of vehicles and people than are the males resident in

the same area, this would appear to be the most

reasonable explanation.

Figure 38 shows the times of activity of elephants

at the Lahugala Tank, expressed as number of

elephant-hours per hour for the months of March,

July, October and December of 1967 and February

of 1968. It summarizes nine days of observation in

March, six days in July, three days in October,

eight clays in December, and three days in February. For all months the same trend is present in

that very few animals are out in the tank before

0700 to 0800 hours when they emerge from the

forest. The general trend then is for the number

of animals present in the tank to build up to a

peak some time between 1500 and 1600 hours. In
NUMBER 125

16

55

14

I/)

05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20

TIME

FIGURES 36.—Times and numbers of observations of elephants in Ruhunu National Park.

March and December the number of elephants present in the tank continued to increase right up until

dusk, but in the other three months the number

of animals began to decline after 1700 hours. Figure 38 shows only the data collected during daylight hours. Data collected by observers working

in shifts throughout the night in both December

1967 and February 1968 showed that for five nights

of observations at least, the number of animals in

the tank began to decline more rapidly between

2000 and 2400 hours and that most of the animals

were gone by 0200 to 0300 hours. On only one occasion was a single male present in the tank

throughout an entire 24—hour period and this was

an old-looking and emaciated male who had remained in one particular area bordering the tank

and just at the edge of the tank for a period of

four days.

The differences between the months December,

February, and March, which show a large number

of elephants present in the tank, and July and October, which show a relatively small number, are

due to the fact that elephants use this particular

tank for feeding. Lahugala Tank is very shallow,

and during the growing season (which begins with

the onset of the rains in late October and November) contains a lush growth of grasses. It is these

grasses on which the animals feed. By July the

tank is relatively dry and the growth of grass has

died back somewhat.

Patterns of Activity

Figures 39 and 40 show typical observations of the

types of activity patterns displayed by males and

herds, respectively. Figure 39, for five solitary

males and two male groups, shows the typical pattern of alternation between periods of feeding and

walking. The lengths of feeding bouts are variable,

but periods of walking without feeding are generally quite short. Feeding includes some locomotor

components, as an elephant generally tends to feed
56

CO

z

O

<

hi

CD

O

LL

O

cc

UJ

CD

5

4

3

2

1

0

1

2

3

4

5

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Gal Oya

Yala

Males

Females

05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20

TIME (HALF-HOUR INTERVALS)

FIGURE 37.—Times and numbers of observations of drinking and bathing by elephants in the

Gal Oya region and in Ruhunu National Park.

at one spot for only a few minutes. He then moves

one to several steps and begins to feed again.

The data obtained for herds shows a similar

trend of alternation. All of these protocols but the

last (Figure 40:5) show a high degree of synchronization between the members of the groups, although

there are slight exceptions. For example in the

second observation one female only stopped to

drink and bathe at a waterhole while the others

walked past. Similar exceptions are found in example 3 where one infant lay down three times

(each time in the shade of its mother) and two

males also lay down for a few minutes. This incidentally, was the only occasion on which adults

associated with a herd were observed to lie down

(see p. 45). In the fifth example the subadult male

began following the juvenile (presumed to be a

female) and was attempting to rest his trunk along

her back (typical precopulatory behavior) as they

disappeared into the forest.

FEEDING PATTERNS

Table 7 summarizes a number of observations of

the rate of feeding by both males and females. The

elephant, when feeding, takes a relatively small

portion of food with each mouthful. Several samples were collected of food or potential food that

had been dropped by the elephant and other attempts were made to simulate elephant feeding by

collecting what appeared visually to be a similar

amount of a particular type from which an elephant had been feeding (p. 95). The average

weight of such a mouthful is about 150 grams.

Therefore, to take in the required daily input of

150 kilograms or perhaps more, a large number of

mouthfuls must be taken during every 24-hour
NUMBER 125 57

TABLE 7.—Feeding rates of elephants

Date and

type of food Sex I Age

Rate

Number of Time (mouthfuls/

mouthfuls (min:sec) min.)

GRASS

3 Mar. 67

3 Mar. 67

3 Mar. 67

22 Apr. 67

2 July 67

2 July 67

2 July 67

1 Aug. 67

1 Aug. 67

5 Aug. 67

10 Aug. 67

10 Aug. 67

11 Aug. 67

11 Aug. 67

SHRUBS

30 June 67

8 July 67

8 July 67

8 July 67

11 Aug67

SHRUBS and

2 July 67

4 Aug. 67

FRUIT

30 June 67

GRASS

9 Aug. 67

9 Aug. 67

9 Aug. 67

11 Aug. 67

11 Aug. 67

11 Aug. 67

9 Aug. 67

9 Aug. 67

13 Mar. 69

13 Mar. 69

14 Mar. 69

8 A

S A

$ A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

8 A

GRASS

8 A

8 A

8 A

9 A

9 A

9 A

9 A

$ A

9 A

9 J

9 J

9 A

9 A

9 A

6

13

15

13

5

3

4

7

21

14

10

8

4

7

5

5

5

17

21

14

30

9

12

10

4

6

6

2

5

3

7

7

6:00

15:00

15:00

30:00

10:00

1:30

2:15

5:00

27:00

10:00

10:00

4:00

2:00

4:00

10:00

3:30

2:45

2:15

9:00

17:00

12:00

10:00

5:00

5:00

5:00

2:00

3:00

4:00

5:00

5:00

3:00

10:00

5:00

1.0

0.9

1.0

0.4

0.5

2.5

1.8

1.4

0.8

1.4

1.0

2.0

2.0

2.0

0.7

1.4

1.8

2.3

1.9

1.2

1.2

3.0

1.8

2.4

2.0

2.0

2.0

1.5

0.4

1.0

1.0

0.7

1.4

period. The rate of food selection, however, is not

uniform. The rate of feeding may be as low as

one mouthful every 2 minutes yet may be as high

as 2.5 mouthfuls per minute when feeding on

grasses or shrubs. The single observation of 3

mouthfuls per minute was of an animal which was

feeding on tamarind (Tamarindus indica) fruits

picked from the ground under the tree, and each

mouthful consisted essentially of one or perhaps

two fruits. The majority of observations fall between 0.5 and 2.0 mouthfuls per minute, although

the distribution tends to be relatively bimodal with

peaks around one-half to one mouthful per minute

and again around \i/2 to 2 mouthfuls per minute.

Figure 41 shows a more detailed analysis of feeding

for three adult males where the differences in feeding rates are not necessarily a reflection of the type

of food being used but rather are a manifestation

of alternate periods of relatively intensive and more

relaxed feeding. As described earlier (p. 46), feeding, especially when feeding on such plants as lowgrowing shrubs or grasses, is not necessarily a simple operation but actually involves a relatively

complex sequence of movements.

Table 8 summarizes 15 observations each of

TABLE 8.—Distances moved and average rate of

movement of elephants while feeding

Date

Time Length of Distance Average

observations observation moved rate

begun (min) (m) (m/hr)

MALES

25 May 68

12 Nov 67

8 Oct 67

10Jun68

10 Oct 67

10 Jim 68

15 Jul 68

5 Aug 67

12Aug67

3 Mar 67

29 Oct 67

12 Aug 67

1 Aug 67

28 Feb 67

28 Feb 67

0547

0630

0700

0750

0930

1350

1420

1505

1533

1600

1602

1625

1647

1650

1650

FEMALE HERDS

19Jun68

19Jun68

8 Apr 68

24 May 68

10 Oct 67

16 Mar 68

10 Apr 68

6Jul 68

14 Feb 68

15 Feb 68

6Jul68

18 Mar 68

15Jun68

!7Jun68

7 Apr 68

0635

0755

0855

0937

0930

0955

1015

1115

1140

1320

1323

1420

1445

1520

1633

25

540

53

30

270

30

60

25

60

210

50

12

35

30

15

30

60

170

25

270

50

240

45

120

60

60

100

120

90

30

100

100

600

75

100

20

500

150

500

250

120

250

120

150

100

20

100

25

100

100

50

1200

50

250

100

250

120

250

350

150

120

10

720

150

20

40

500

360

500

70

150

1500

220

300

400

40

100

10

240

20

60

300

60

125

100

250

70

125

230

300

Mann-Whitney U test; U — 60
58 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

16 —

o

Q 14

Q) 12 —

£10 -

l

8 "

"a e —

E

• C 4 —

<

IV 2 — fl

MJODF MJODF MJODF MJODF MJODF MJODF MJODF MJODF MJODF MJODF MJODF

0600 0700 0800 0900 1000 1100 1200 1300 1400 1500 1600

FU.LRE 38.-Times of activity of elephants at Lahugala Tank. MJODF = May, July, October,

December, February, respectively.

MJODF

1700

males and female herds where it was possible to

measure or estimate with relative accuracy the distance moved by animals during a period of feeding.

The distances moved and average movement rates

are quite variable, from as low as 10 meters per

hour to as high as 1.5 kilometers per hour. There

does not appear to be any correlation between the

movement rate and the type of food being utilized

nor is there any apparent correlation with the time

of day. There is, however, a significant difference

between the movement rates while feeding between

males and females with young, the latter feeding

and moving at a slower rate.

TIME AND ENERGY BUDGET

As can be seen from the examples of protocol which

were outlined above (Figures 39, 40), it is not possible to assign a particular time and energy budget

which will apply to all individuals or all groups;

rather, the amounts of time that an animal or

group of animals will spend in any particular activity will vary from day to day. Certain general

trends, however, can be drawn from these data.

For example, the five protocols of herds where observations were recorded in detail for all individuals plus a further two, which were not included

in Figure 40, give a total of 185 animal-hours of

observation. Of this total, 167.5 animal-hours or

91.1 percent were spent in feeding, including locomotor components of feeding. The next largest

category was that of locomotion or walking without

feeding which occupied 9.6 animal-hours or 5.4 percent. The remaining 3.5 percent was divided between resting (1.4%), bathing (1.8%), drinking

(0.1%), and all other activities combined (0.2%).

A similar estimate based on a much smaller sample size of 15 animal-hours for solitary males (Figure 39) gives 87.1 percent feeding, 10.1 percent

walking, 2.0 percent resting, and 0.9 percent for

all other activities combined. A much larger sample from Lahugala Tank for males is presented in

Table 9 for daytime hours only, which include data

from tour observation periods over a total of over

108,000 animal-minutes or 1600 animal-hours. Of

TABLE 9.— Time and energy budget for male

elephants at Lahugala Tank

Activity

Feeding

Walking

Contact-promoting

Play/Aggression

All other

Total

Total

animal-mins

101,223

2,091

52

3,593

1,052

108,011

Percent

93.5

1.9

0.3

3.3

1.0

100.0
NUMBER 125 59

1

2

3

4

5

6

7

Cf Ad

24 x 67

Cf Ad

12 xi 67

d*Ad

03 iii 67

Cf Ad

08 x 67

Cf Ad

14 iii 69

3Cfcf

28 ii 67

266

16 vi 68

F

I I I

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1 II

0630

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w

16

r

0715

SW

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 F

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 F

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1520

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II II 1 1

10

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ii " nil II

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1730

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1 1

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1 II II II II 1

0 9

1 1

0

18 19

]

18

L

L..

FIGURE 39.—Observations of activity patterns for five solitary males and two male groups. D =

drink, Def=defecate, F —feed, Ozrorient toward observer or other stimulus, R = rest, S=stan

W—walk.

this total, feeding occupied 93.5 percent, movement

1.9 percent, play and agonistic behavior 3.3 percent,

and all other activities combined 1.3 percent.

Within those 24—hour periods when it was possible to observe animals during the night, the relative proportions of resting or sleeping to feeding

or other activities did not vary significantly from

the daytime hours. Even if an elephant were to

sleep for two hours during the night which appears

to be much longer than would be expected, the

total time spent in feeding would still be in the

order of 80 percent. Several factors can, however,

influence the percentage of time spent in various

activities for given individuals. For example, two

animals, both males, which were observed frequently for short periods were undoubtedly ill.

The first of these was the male mentioned on page

55 who was observed for a period of several days

at Lahugala Tank. He spent approximately 20 to

30 percent of his time, depending on the day, in

resting (often leaning against a tree). Another

male, at Amparai, had been shot by cultivators and

for a period of slightly more than a week was observed every day resting in the tank. On one typical

day, for example, he spent approximately two hours

standing and resting in the water and only a half

hour, of the total 2]/2 hours observations, feeding.

Social interactions can also occupy fairly large

proportions of time for particular individuals. For

example, Figure 42 shows the relative amounts of
60 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

1

10 » 68

3A

2 1

1115 1200

25 x 67

A i

A2

A3

SAi

Ji

F

F

F

F

F

A4

SA2

SA3

J2

W

w

w

w

ww

w

iDBlw

IW

F

F

F

F

F

F

F

F

IW

IW

IW

IF

IF

IF

1600 1700

18 i 69

•OUp1

A

SA

A

A

I

I

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SAd1

SArf

Acf

F / W

F

F

F

F

W

F

F

F

F

F

L IW L

Iwb IF

ML |w

J

B If

F

F

1500 1600 1700

10 iv 68

A

I

A

A

A

J

I

F

F (S]F

F

W

F

F

F

R

R

R

0

I

F

F

F

JR

I

IB IR

IW IF

lW IF

|W~|F

IW IR IB IR IB IW IF

1015 1100 1200

F

F

F

F

F

F

F

R

R

R

R

R

R

R

p

-

F

F

F

F

1300 1400

Tl iv 68

A

A

SAtf

SA

J

I

F

F

F

F

F

F

IW 1

IW 1

IWJF

IT IF

|T|F WlRb IF IT IF lW

W 1

I WI

IW I

0820 0900

FIGURE 40.—Observations of daily activity for five herds. A = adult; B —bathe; D=drink; F =

Feed; I —infant; J—juvenile; L —laying down; N —nurse; R = rest; Rb=rub against tree;

T= throw dirt on back; W=walk.

time spent in various activities by one particular

subadult male for a period of six days. On the

first, third, and sixth days of these observations he

spent a relatively large proportion of time in interactions with other individuals in the area. The

other days he spent primarily feeding. A further

record of time spent by an individual during social

interactions was of a male who was associated with

a herd containing one or possibly two females in

estrus at Lahugala during 1967. This was reported

by Eisenberg, McKay and Jainudeen (1971:215).

Of 100 minutes of observation, 23.35 were spent in

sexual behavior, 18.35 in contact-promoting behavior, and 58.3 in feeding and other activities not

connected with his interactions with females. Of

the 58.3 minutes, 45.9 were spent actually feeding.
NUMBER 125 61

d A7

11 viii 67

05 viii 67

I I I I I I I I II II III til l I I I I

1015

I WALK W

I I I I I I I II I L L

1507

03 iii 67

I I I I I I I I I I > I II I I I I I

1616

M I I I I I

10 15 20 25

Mi nutes

FIGURE 41.—Detailed analysis of feeding for three adult males showing alternation between

periods of intense and more relaxed feeding.

From these latter observations it would appear that

even though social interaction is indeed important

to the elephant, a large percentage of time still

must be spent in feeding regardless of the necessity

for interaction with other individuals.

Data on the activity rhythms of Loxodonta are

not as yet available. Data such as those presented

by Blood (1963:91) for the bighorn sheep (Ovis

canadensis) show a pattern typical for a largely diurnal ruminant, i.e., three peaks of activity (movement versus nonmovement) with intervening

periods of inactivity.

The most interesting data available for comparison are those of Clough and Hassam (1970) for

the warthog (Phacochoerus aethiopicus), for which

they establish five classes of activity and present in

their figure the relative proportions of each perhour of daytime observation. Their data for the

warthog show several similarities to mine for the

elephant in that there is on the average an apparent

alternation of types of activity rather than specific

peaks. The warthog also shows a predominance of

feeding followed by walking as the major activity

types.

Schenkel and Schenkel-Hulliger (1969) discuss

the activity patterns for the black rhinoceros (Diceros bicornis) but do not make any attempt to construct a time-energy budget. They do point out

one facet of rhinoceros behavior which contrasts

with the elephant—the black rhinoceros apparently
62 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Mar 6

8 F

p

9 F

p

10 F

11 F

•2

TIM E

FIGURE 42.—Activity pattern of a subadult male over a period

of six days (Lahugala Tank). W = walking; F —feeding;

P=play-fighting; time scale = hours of day.

frequent areas of contact being the ear, mouth,

eyes, temporal gland, tail, anus, feet, and genitalia.

The neck and head region are also examined on

occasion as may be the mammae, if the animal is a

female. Occasionally examination of the genitalia

and anal region may be followed by insertion of

the trunk into the mouth (p. 65).

PATTERNS OF INTERACTION

Following initial contact, the responses of the interacting animals are highly variable. Some of the

potential response and interaction types, are considered under separate categories of interactions

with little or no contact and interactions with extended or repeated contact.

comes to water only at two to three day intervals,

as opposed to one or more times per day for Elephas.

Social Behavior

INITIAL ENCOUNTER

Whenever two elephants are in the same vicinity,

the first indication that one has become aware of

the presence of the other is generally the extension

of the trunk by one or both in the direction of the

other. This is generally followed by orientation of

the body axis towards the other animal, often accompanied by an extension of the ears. On at least

two occasions, however, in Ruhunu National Park,

two males were observed to be moving at approximately the same time over an open area and the

only noticeable reaction was the extension of the

trunk totally unaccompanied by any other response.

This initial response may be followed by either

approach or avoidance by either one or both of the

animals involved.

When one elephant approaches another, the

trunk is generally extended forward towards the

animal being approached. The ears may or may

not be held extended depending upon the situation, and the head is generally held in the normal

position or may be raised slightly. Initial contact

between two animals generally involves mutual examination by both animals; the trunk tip is extended towards the other individual, the most

Interactions with Little or No Contact

The following four examples are taken from field

notebooks and represent typical male-male interactions.

1. 24 September 1967, Yala, Heen Wewa, 1643 hours: A

large male which has visited the tank on the previous day

walks down the roadway, crosses over the bund with his penis

partially erect, walks down into the water and wades to the

far side, a distance of approximately 50 meters. About 2

minutes later a second male approaches from the same direction as the first one. The second male comes up onto the

bund and stands facing the water. The second animal now

goes down across the bund; the first turns and faces the

second as the latter enters the water and begins to drink.

After drinking, the second animal throws water over the sides

and back. The first animal now begins to move across the

water toward the newcomer. As the first male approaches

the newcomer, the second male turns sideways presenting

his side to the first animal.

At about this time, a third male appears on the far side

of the tank approximately 150 meters away from the two

under observation. As the first male approaches the second,

the penis of the second is partially erected. Both animals

extend the trunks toward each other but there is no contact

between them. The first animal has now come up out of

the water and is standing on the bank. The second animal

also moved out onto the bank and the two stand side by

side facing the same direction. During this time, the third

animal has approached the tank and is standing in the water.

The third animal has not been observed to react to the

presence of the first two nor have the first two shown any

response to the third.

2. 5 November, 1967, Kitulana Tank, 1725 hours: A large

adult male comes out into the northwest corner of the tank

and another large adult (a tusker) enters the tank from the

eastern side. The two begin moving: the first tuskless male
NUMBER 125 63

moving along the edge of the tank towards the east and the

tusker crossing the tank moving towards the west. At 1740,

the two meet and begin to move towards the east, coming

out into the tank. Both stop to feed at the edge of the tank,

then continue on eastward feeding occasionaly until at 1750

they disappear at approximately the same point where the

tusker came out of the forest. During the entire period of

observation, there was no actual contact between the two

animals.

3. 14 November, 1967, Lahugala Tank: A large male has

been feeding out in the tank since 1050. At 1200 hours a

second male comes out and moves towards the first. At 1203

the second animal stops about 150 meters away, standing

facing the first animal, but not showing any signs that it is

aware of the presence of the first animal. Three minutes later,

the newcomer begins to walk out into the tank moving

toward the south; the wind at the present moment is from

the northeast and the original animal is to the east of the

newcomer. After walking for about H/2 minutes, the newcomer turns and faces the first animal (they are now about

20 meters apart). The newcomer begins feeding and continues moving towards the first one. As they come to within

about 5 meters, the first animal raises its trunk in the direction of the newcomer; the second animal also raises his

trunk and as they make contact there is mutual trunk to

mouth contact. The animals then walk past each other and

at 1209 continue feeding. By 1245 they have moved approximately 200 meters apart and by 1345 they are about 500

meters apart.

4. 4 November, 1967, Kitulana Tank, 1745 hours: A large

adult male who is in musth is feeding in the tank along with

a herd of females and juveniles. At 1751 another adult male

comes out on the opposite side of the tank. The male in

musth orients towards the newcomer, extending his trunk,

and then begins to approach. After the male in musth has

gone 100 meters the new male turns and begins to move

away. The male in musth breaks into a fast walk and the

newcomer increases his pace to a run. As the new male disappears into the forest, the male in musth turns and walks

back and rejoins the herd of females.

As these examples demonstrate there can be a

wide range of responses on the part of an animal

once he becomes aware of the presence of a conspecific. There does not need to be any contact between animals in order to have an interaction as

is amply demonstrated by example 4.

The animals involved in examples 1 and 3 were

seen together on other occasions besides the ones

described here. For all of the first three examples,

one can reasonably conclude that the interacting

animals were familiar with each other. The fourth

example, involving an aggressive chase, is not intended to imply that males in musth are constantly

aggressive. This same animal tolerated the presence of a third male. For a further discussion of

musth, see Jainudeen, McKay, and Eisenberg (n.d.).

Interactions with Extended Contact

In encounters between two adult females, there is

seldom any interaction beyond the initial contact

which includes investigation with the trunk of the

portions of the body mentioned earlier. More complicated interaction patterns are observed, however, between adult males and adult females and

between juveniles of both sexes. The following

three examples will illustrate the variety of interactions observable.

1. 23 July, 1967, Lahugala Tank, 1615 hours: A group

of two adult females, three young, and a subadult male

tusker enters the tank and begin feeding. At 1655 two

subadult males of the same size as the subadult tusker appear

at the edge of the tank about 75 meters away from the group.

The two new males approach the group and one of them

extends his trunk towards the genitalia of the larger adult

female; he then turns and puts his trunk to his mouth. By

1702 the group has moved slightly to the northwest and the

two new males are following behind. At 1708 the two young

males moving together approach the subadult tusker. The

tusker backs off swinging his trunk. The two newcomers turn

and run towards the bank, one of them actually leaving the

tank and going up onto the bank. The subadult tusker follows this animal, rushing head on toward it with his ears

extended. He rams the side of the other male with the base

of his trunk, not with his tusks, and then as he backs off

he swings his trunk in the direction of the male. He then

repeats this rush and butting a further two times. Between

charges, he gives one of the threat displays which involves

the kicking of dirt, throwing the dirt over his own back, and

swinging the trunk in the direction of the other male. After

the third attack, the newcoming male dashes into the forest;

the young tusker follows him into the brush and about 30

seconds after he disappears from sight there is the sound of

squealing from the area where the two disappeared.

2. 12 February, 1967, Lahugala Tank 0910 hours. Four

adult males are feeding in the tank and two others are

standing on the north bank. Two of the adults engage in

typical contact-promoting behavior but soon continue feeding, moving toward the center of the tank, in a loose group.

At 1018 one of the animals which had been in the tank the

longest time (which I shall call A) approaches the larger of

the two new males (B) and begins to rub his trunk base

against the forehead of B. B then extends his trunk around

the trunk base of A. A now turns and they stand side by side.

He then takes a step backward, lifts the head up and with

the mouth open extends the trunk over the back of B. As

B turns now to face A, A's trunk and mouth are over B's

neck. They break and A moves around approximately 180°

to a position behind B and extends his trunk along B's

back. B now moves away; A follows extending the trunk

along the back again with the mouth open this time. Again
64 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

B moves away. A follows and again puts the trunk along the

back with the mouth open. B continues moving and A follows with his trunk along the rump of B. After they have

gone about 20 meters, A breaks away and both animals begin

feeding. They feed for 5 minutes with A standing side by

side with B. Then at 1024 A extends his trunk to the anal

region of B, then puts his trunk up over the back of B and

pushes B down into the water. B gets up and A pushes with

his trunk base against B's rump but this time B does not

go down, instead he remains standing with his flank towards

A. A continues pushing with the base of the trunk, then

raises his trunk over B's back and pushes downward. B goes

down into the water again. A now has his head down below

the level of the grass butting at B; B gets up again. A again

pushes against B's rump with the base of his trunk and

forehead. This again results in B falling down into the water

but this time when B rises he faces directly toward A. A

now lifts his trunk and head over B's head and presses downward forcing B into the water a third time. B gets up and

moves away about 3 meters. A then turns to a position

behind B and mounts him with forelegs extended along B's

back and during the mount which lasts about 30 seconds he

is hitting B's head with his trunk. A dismounts as B moves

away. B turns and stands facing A with trunk extended and

ears forward. This same type of pattern continues with two

more attempted mounts and with continual butting and

extension of the trunk over the back until 1051 when both

animals begin feeding.

3. 30 June 1967, Ruhunu National Park, Gonagala: Two

males are standing in the tank; one is a large adult male, the

second is the subadult with crossed tusks. At 1745 the larger

moves up onto the bund. At 1750 the tusker follows, feeds

from a small shrub and then stands scratching the inside

of his left forefoot with the right forefoot and with his trunk

resting on his tusks. He then turns, touching the side of his

head with his trunk tip, and begins pawing with the left

forefoot at the dirt. The larger male is now moving. The

tusker follows, moves along side the larger male, and they

make trunk to trunk contact. The tusker then backs away.

Time is now 1757. The larger male approaches the tusker

who continues to back off. They stand about 10 meters

apart for 2 minutes, then the larger male again approaches

the tusker. The tusker kicks at the dirt with his left forefoot

and they make trunk contact again. Both animals now turn

and begin to move away to the north. The tusker passes the

larger male; they both stop and again make trunk contact

as they stand side by side. The larger male now extends his

trunk towards the temporal gland region of the tusker and

both extend their trunks over the neck of the other. The

tusker suddenly lowers his head and then raises it rapidly

pushing his tusks up under the jaws of the larger male who

then faces the tusker. The large male is now standing with

his hind feet spread apart somewhat. Both animals again

extend their trunks to the head of the other and the large

male jerks his head upward attempting to throw his trunk

over the head of the tusker. The tusker again rams his tusks

under the jaws of the larger male, then turns and the two

are now standing side by side. They again make trunk tip

contact and the larger animal swings his trunk up over

the neck of the tusker. The tusker turns so that he is now

facing the side of the larger male and the two animals begin

pushing; the larger one with the forehead and the tusker with

the side of his right tusk. They break and turn standing to

face each other. The tusker then swings his head and trunk

toward the large male who backs off slightly, also raising

his head. The tusker then backs off two steps, stops, turns,

rubs the side of his head with his trunk, then rushes at the

larger male swinging with a lateral motion of the tusks, hitting the larger one on the side of the head. The larger animal keeps pressing forward and the tusker delivers two

more lateral blows with the right tusk. The larger animal

continues pushing and the tusker turns to move away raking

his tusk along the side of the larger male. The larger male

then moves away. The tusker turns, approaches him, and

the larger one continues moving, stops, and then backs up

rapidly hitting the side of the tusker with his rump. The

tusker then backs up and abruptly the interaction is over.

Time is now 1808 hours and both animals begin to feed.

Clearly the first example is an aggressive response. The third example would also appear to

be primarily aggressive. The second, however,

poses a number of problems; there are not only

patterns which would be associated with aggression, as outlined in the other two examples, but

also patterns which are more frequently encountered during sexual behavior as described by Eisenberg, McKay, and Jainudeen (1971). Two other

patterns have been observed which did not occur

during any of the three encounters; these are the

grasping of the tail of the second animal, putting

it into the mouth, and biting, and kicking with

one of the hind feet after backing into an animal.

All of the patterns described above, including

the last two, have been observed, not only between

adult males but between juvenile animals of both

sexes. Juveniles, and to a certain extent infants,

play among themselves for quite extended periods

and during these episodes of play, the patterns described above which could be grouped into contactpromoting, sexual, and aggressive are displayed

quite regularly. These observations thus raise two

questions. First, is the play of juvenile elephants

a mechanism for developing and practicing motor

patterns which will eventually be displayed under

particular discrete motivational states in the adult;

and second, is it possible to define a discrete motivational state in the adult except under particularly extreme circumstances? In other words, do

complex motivational states exist in the adult

which result in complex patterns of behavior resembling the play of the juveniles?
NUMBER 125 65

With field observations of this nature, it is impossible to answer these questions adequately without detailed experimental studies on animals of

a known social background. In these field observations, we have been dealing with animals whose

previous history is totally unknown and two males

who are observed as adults interacting in an aggressive manner for at least part of the interaction

may have been raised together as juveniles or at

least may have known each other as individuals

since attaining puberty. It could be hypothesized

that under such circumstances an interaction which

begins as an aggressive interaction could become

complicated by the fact that the two animals are

known to each other, having shared some previous

social experience, and from this a conflict could

arise between aggression and contact-promoting behavior. For these reasons I have termed all interactions of this sort "play-fighting," not to imply

any functional significance but simply to emphasize the similarity between the behavior of adults

and juveniles. Other evidence from the spacing

and grouping of males would tend to support the

above hypothesis (pp. 82-85).

Interactions between Males and Females

Example 1 (p. 63) illustrates a frequently observed series of acts which occur when a male approaches a herd of females. The response of the

females to such initiation of contact by a male

varies. The female may apparently ignore the male

but more frequently will respond by extending her

trunk toward the male's head. Such contact-promoting behavior may lead eventually to sexual behavior should a female be in estrus as was observed

on 14 November 1967 (Eisenberg, McKay and

Jainudeen, 1971:214-215) at Lahugala and on one

other occasion, 11 April 1968, at Inginiyagala.

On one occasion an adult female was observed

to react aggressively to a male who approached her

group. On 13 June 1968, at Hatpata, a number of

groups were feeding in the open in the mid-afternoon. At 1715 one male, who was also feeding in

the same area, approached one of the groups. He

made trunk to genitalia contact with one female

and moved on toward another. As he moved toward the center of the group, the largest female in

the group (an animal we had named Big Fanny)

turned and rushed toward him. The male turned

and moved at a fast walk toward the forest, Big

Fanny following. After about 75 meters Big Fanny

returned to the group. Five minutes later the male

returned to the group and again Big Fanny ran

toward him, chasing him about 150 meters.

Such aggressive interactions between males and

females were not observed frequently. No instance

of aggressive interaction was observed between

females.

COM M u N ICATION

Tactile and Chemical

As the external organ of olfaction and the primary

organ of tactile sensation in the elephant are combined in the trunk, it is appropriate to consider

the two together. Examples have already been

discussed of the manner of deployment of the

trunk in picking up scent presumably from objects

in the environment and from the wind, and

further discussion on this point is unnecessary.

Particular mention should be made, however, of

the action of placing the trunk tip into the mouth

following the sniffing at an object, especially of

urine. According to Eales (1926), the African

elephant, Loxodonta, has a jacobson's organ with a

patent opening into the buccal cavity. Examination

of the mouths of two Ceylonese elephants showed

that Elephas also has a visible jacobson's organ.

Whether this organ is functional in Elephas is

unknown but from the behavior of the animals it

would appear likely. Potential chemical signals in

the elephant include feces, urine, odors from the

body rubbed off onto trees, secretions from the

temporal gland of the male, and of the interdigital

glands. During contact behaviors the trunk tip, as

mentioned previously, is extended to various parts

of the body of the second animal and during such

contacts it is impossible to say whether chemical

information or tactile information is the more important.

Visual Communication

Although Rensch (1959) has shown that the visual

acuity of the elephant at close distances is good, it

would appear that its acuity at greater distances is

poor or at least that elephants rely very little on

vision for obtaining information about their en-
66 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

vironment. As long as one remains silent and

downwind, one can move about to a certain extent

in the vicinity of elephants as close as 10 meters

without attracting their attention. Rapid movement or movement over a large distance will, however, draw their attention. Also on two occasions,

the elephants under observation approached very

close to the observers and would undoubtedly have

blundered into them had not the observers reacted.

Nevertheless, it would appear that visual signals

may occasionally be used in interactions between

the elephants. One example would be the aggressive approach in which one animal approaches the

second with the head raised somewhat and the ears

extended forward or rather laterally. The position

of the trunk and head may also give a certain

amount of information to other animals in the

group about the motivational state of a particular

individual. Kuhme (1963) has attempted to describe postures for the African elephant which could

be related to certain motivational states, ranging

from the normal position of the head through 19

variations depending upon the angle of the head,

and position of the ears and trunk. From my own

observations, the postures (or to be more correct,

movements) of the various organs of the head are

as follows: In mild arousal or excitement, the

ears are extended at a 90° angle from the body axis

and the trunk is generally extended towards the

stimulus causing the arousal. As lateral mobility

of the head is limited, the body axis is usually

realigned so that the animal faces the stimulus. In

a mild or perhaps confident aggressive approach,

the animal approaches the stimulus with the head

raised and ears extended; the trunk is extended

toward the stimulus.

Three other patterns containing aggressive components also occur. The first two can be considered

threat gestures. In one threat gesture, the animal

stands facing the stimulus. Dirt is kicked with one

foot, using the same motion as in scarifying for

feeding, although this action often appears to be

more exaggerated. The dirt is then collected in the

"hand" of the trunk and thrown over the back and

then the trunk is brought slowly down and held

for a few seconds in the direction of the stimulus.

Throughout this display, which is undoubtedly

entirely visual, the ears are held extended.

The first display is very similar in some of its

components to the pattern of throwing dirt on the

back (always repeated) often seen after bathing. It

is, however, more exaggerated in the movements of

the trunk and foot. The foot may be kicked forward

to a 45° angle to the body during this display,

whereas during normal scarification it is generally

halted close to the ground and almost vertical. It

would seem possible that this display may have

evolved by a process of classical ritualization

(Tinbergen, 1952) from a displacement activity.

In connection with this particular threat display

it is instructive to look at one of the techniques

used by certain trackers to deter an elephant from

approaching too close. Piyadasa, a tracker at

Ruhunu National Park, told me of a favorite charm

used by many old jungle men which, besides the

verbal component (spoken, not shouted, incidentally), involves picking up a handful of dirt

and throwing it up in the air, leaving the arm

briefly in the laised position. Piyadasa who himself

demonstrated this charm for me on several occasions

was apparently unaware that he was mimicking the

actions of the elephant.

In the second display which is described both by

Tennent (1867) and by Sanderson (1878), the

elephant faces the stimulus with head lowered

slightly and the ears extended. The trunk is held

resting on the ground, raised slightly, and bounced

hard on the ground. As the trunk hits the ground

the animal exhales through the trunk producing a

snort and the combination of the snort plus bouncing of the trunk tip on the ground produces a

booming sound which can be heard for a great

distance. The effect of this threat is primarily

auditory. During attack, the head is lowered, the

ears are held back against the side of the neck, and

the trunk is curled ventrally. If the object of the

attack is another elephant, the atack generally

culminates in butting with the head of the attacker

against the side of the animal being attacked. An

animal presumed to be submissive generally turns

away from one displaying the aggressive posture.

The postures or movements described by Kuhme

(1963) as being defensive are typical movements

displayed by an animal which could be considered

to be in a conflict situation between a tendency to

attack and a tendency to flee.
NUMBER 125 67

Auditory Communication

Elephants have a relatively large repertoire of

vocalizations (Table 10; Figure 43). Muckenhirn

(1967) has shown that mammals can modify certain basic sounds in a variety of ways (i.e., by

changing the amplitude, temporal patterning, or

stressing of overtones), thereby producing a relatively large repertoire of noises using a relatively

small number of basic sounds. This same pattern

appears to be true for the elephant. The various

sounds of the elephant differ markedly in amplitude, some being of low volume and audible only

at close range, others being extremely loud and

audible for several miles. The temporal patterning

can also be changed. The elephant can also emit

sounds through the mouth or the trunk, which

appears to act as a resonating chamber changing the

subjective quality of the sound emitted.

If we take, for example, the low amplitude growl,

which appears to be a short distance contact call,

and resonate this sound through the trunk it becomes more of a rumbling growl with a clearly

resonant quality. This growl appears to be employed primarily during mild arousal. The same

growl can be increased in amplitude without any

apparent resonance through the trunk to produce

the roar. This roar is a long distance contact call

used primarily by juvenile animals who have been

separated from their groups, but also used by

adults. By apparently lengthening the time between

pulses and increasing the amplitude, the elephant

produces the long distinctly pulsed roar which can

best be described as similar to a small motorcycle.

This latter call has only been heard used by females

answering their young who were roaring. All of

these calls appear to be essentially pulsed calls and

of a relatively low frequency as measured by stress

on the lower harmonic.

The other basic vocalization of the elephant is a

squeaking call which appears to have the stress

primarily on higher harmonics. Two variations of

this have been heard and recorded. The first is a

series of short squeaks ("chirping," Figure 43)

which was heard in a variety of contexts and the

actual significance of which is uncertain. Sanderson

(1878) describes this as being a pleasure call. I

have recorded this call given by a captive animal

at the National Zoological Park, apparently as a

greeting to the keeper when the keeper enters the

cage. This call has also been heard in the wild in

Ceylon, but in each instance the animal giving the

vocalization was in a state which could be described

as conflict between attack and flight. The same

basic call when given as a single protracted sound

of extremely high amplitude becomes the scream

or trumpet which is given generally at the time of

initiation of flight. This was most frequently heard

when elephants had been startled by the observer

or some other human, but was heard once during

an aggressive interaction between two males. Both

of these calls appear to be resonated through the

trunk to some degree, although the correlation

between these calls and resonance through the

trunk is not certain. Eisenberg and Lockhart

(1972) mention an instance of a trumpeting sound

being given immediately prior to attack. I have

also observed the trumpet to be used in such a

situation only once. A captive female Loxodonta

TABLE 10.—Vocalizations of Elephas maximus

Basic sound Modified by Resulting sound Context

Growl 1. None

2. Resonate in trunk

3. Increase amplitude

4. 3. + change pulse rate

Squeak 1. None

2. Multiple short squeaks

3. Lengthen, increase amplitude

Snort 1. None

2. Increase amplitude

3. 2. -|- bounce trunk-tip

on ground

Growl

Rumble

Roar

"Motorcycle"

Chirping

Trumpet

Snort

Snort

Boom

Short-distance contact

Mild arousal

Long-distance contact

$ response to 3.

Not heard in wild

Conflict ?

Extreme arousal

Change in activity

Mild to strong arousal

Threat display
KHz

5

0

intensity,.

0

0

0

0

Sec.

FIGURE 43.—Sonograms of sounds made by Elephas maximus. a, snort; b, c, trumpet; d, chirping;

e, roar. Inverted frequency scales show intensity at different frequencies.
NUMBER 125 69

at the National Zoological Park was recorded using

a similar trumpet-like call when aggresively approaching her male cagemate. It is quite conceivable that such a call indicates not specifically

aggressiveness but rather a general phenomenon of

extreme arousal.

Elephants also make a snorting noise, which

although not strictly vocal is an audible sound

produced by exhaling rapidly through the trunk.

The low intensity snort was heard several times in

the field. This can only be heard by the human

observer at very close distance, less than 20 meters,

and appears to indicate that the rest of the group

should follow the action of the animal giving the

call. It can be used either to stop the group or to

start the group moving again, or to cause a change

in direction of movement of the group. It is thus

similar in apparent function to the rumble, although

the rumble is used simply to indicate a mild arousal

whereas the snort can be used both to indicate

arousal and to elicit a response in the nearby

animals. The louder snort is often heard when

animals are surprised. The snort can also be amplified extensively during the threat display described

above where the tip of the trunk is bounced on the

ground at the time of exhalation. This produces

an extremely loud sound which can be heard for a

distance of a mile.

Frade (1955:754) has described a perforation in

the septum of the trunk near the tip, in approximation with two cartilaginous valves. This structure has not been described by any of the early

anatomists, nor has its existence been confirmed by

the author. Should it exist, however, it could provide a mechanism for controlling and varying

resonance through the trunk. Regardless of the

presence of such a structure, it has been noted that

when captive elephants utter calls that appear

to be resonated there is a pronounced swelling of

the bump of the trunk base.

Besides these vocalizations, there are a number

of other sounds, such as flapping of the ears, noises

associated with feeding, flatulation and eructation

which have the potential of containing two signals.

The first of these would be a simple short-distance

contact sound, which could be of importance when

a herd is feeding and moving through dense scrub.

The second possibility is that the sudden cessation

of such sounds, which occurs when a herd is

disturbed by man, could indicate disturbance to a

member of the group who might be somewhat

separated without the need for any vocalization.

On several occasions we encountered groups of

elephants in forest too dense to see them. On most

of these occasions a vocalization (either the snort

or rumble) was heard, but in a few instances there

were none. For example on 16 February 1968, Anil

Jayasuriya, Gomis, and I were walking along an

elephant trail west of Inginiyagala. We halted upon

hearing the sounds of ear-flapping somewhere to

our right. After about 45 seconds all sounds stopped.

Looking through the brush I could see one elephant

who stood at a distance of about 20 meters. He

faced us for a few seconds before turning and

walked silently away. Anil saw at least one other.

As on several other occasions the retreat of the

elephants away from us was completely silent; not

even the sound of rustling branches could be heard.

MATERNAL AND INFANT PATTERNS

When nursing, the female stands in a normal resting posture and the infant approaches her from one

side, putting his head against the axillary region,

then raises his trunk up along the side of the

mother, grasps the nipple in his mouth and begins

to suckle. Small infants generally tend to spend

most of their time in close association with an

adult, even if there are juveniles present in the

group. Sanderson (1878) observed two calves

suckling from one female at the same time. This

was not observed during my field work but on 11

April 1968, at Inginiyagala, a small infant was

observed to suckle from his own mother and from

another adult female which was also in the same

group.

In a group containing infants, there are frequently more adult females than infants. In such

instances, all females appear to share equally in

the care of the young. Whenever the group of

females is feeding in a relatively stationary position,

older infants frequently stray from them and indulge in fairly extensive play behavior. Whenever

the group is moving, however, the infants tend to

remain very close to the females and, if any disturbance is present, the adults form a group with

the infants in the center. At such times, and also

at other times, the infants are frequently restrained

from straying by the adults who will extend their
70 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

trunks around an infant that is about to move away

and pull it back.

The converse frequently happens when the

adults are feeding while the infants play around

their feet. It has been observed several times on

such occasions that the adults will kick the infant,

often sending him sprawling onto the ground. As

the infants get older and begin taking solid food,

they frequently feed along side the head of the

mother. When the mother is feeding on grass, at

least, quite often the infants are allowed to take

food from the handful that the mother has collected.

Organization of Elephant Groups in Time and

Space

GROUP SIZES

Figure 44 includes all of the observations made in

the Gal Oya area from 1967 to 1969, including

multiple observations of particular individual males

and particular herds of females. Individual animals

were frequently observed in groups of various sizes.

For example, a particular female might on one day

be with two other animals and the following day

in a group of eleven. Similarly, with males, an

animal which may be solitary on seven or eight

observations is occasionally seen in company with

another male. Therefore, these data are not to be

interpreted as an indication of stable group sizes,

but rather as an index of the relative amounts of

time that an elephant will spend in a group of a

particular size. These data include all observations where it is reasonably certain that the

total number of elephants present in the group

had been counted. Brief observations of one or

more elephants under conditions of poor visibility

(such as animals seen moving away from the road

as the vehicle or observer on foot approached) are

omitted, as it was not possible under such conditions to estimate the size of the group.

Figure 44 is divided into two sections, one being

those groups that contained at least one adult

female, and the other, those groups that consisted

of one or more males with no females present. The

total number of observations is 120 for groups

containing females and 99 for those containing only

males. The majority of the groups containing

females was small: Of the total observations 50

percent were of groups of 6 or fewer individuals;

75 percent were of 9 or fewer; and 90 percent of

14 or fewer individuals. Groups of 15 or more individuals comprised only 10 percent of the total

observations. For the males, 80 of the 99 observations were of single animals and 14 were of 2 adult

males. The groups of 3 to 5 individuals made up

only five observations out of the 99 or approximately 5 percent. Data for Yala (Tables 11, 12)

show a similar trend where, for groups observed

between February and September 1967, 14 out of

30 observations were of groups between 1 and 5; 7

were of groups between 6 and 10; 6 were of groups

between 11 and 15; and the remaining 3 groups

consisted of between 16 and 25 individuals. Males

for Ruhunu National Park also show a trend

similar to Gal Oya, in that, of 123 observations 101

were of solitary animals, 20 of pairs, and there were

only single observations of a group of 3 and a group

of 4 adult males. Sizes of male groups for Lahugala

Tank (Table 11) were noted as they were seen to

emerge from the forest to enter the tank. Of 170

such observations, 103 were of solitary males; the

remainder being made up of groups from 2 to 7 in

size. These Lahugala data differ quite markedly

TABLE 11.—Composition of elephant male groups

Number in

group

1

2

3

4

5

6

7

> 7

2

Gal Oya

2

80

14

3

1

1

0

0

0

99

Yala

101

20

1

1

0

0

0

0

123

Gal Oya

and

Yala

181

34

4

2

1

0

0

0

222

Wet

season

89

31

16

3

S

1

5

0

148

Lahugala

Dry

season

14

6

1

1

0

0

o

0

22

103

37

17

4

3

1

5

0

170
NUMBER 125 71

TABLE 12.—Composition of Elephant herds

Number in

group

1-5

6-10

11-15

16-20

21-25

> 25

Wet

season

30

29

9

3

2

3

76

Gal Oya

Dry

season

23

13

5

1

1

1

44

2

53

42

14

4

3

4

120

T

Yala

14

7

6

2

1

0

30

Lahugala

Wet

season

5

2

2

2

0

12

23

Dry

season

0

3

0

0

1

0

4

2

5

?

?

1

12

27

from the observations of Gal Oya and Yala in that

only 62 percent represented solitary individuals as

opposed to 80 and 82 percent, respectively, for the

other two areas. Using the average percentages of

the Gal Oya and Yala distributions as the expected

distribution and applying a Chi square test to the

80'

2 0 -

a

o

O)

o

n.

1 5 -

5 -

0 I..

Lahugala data shows that the difference between

Lahugala and the other two areas is significant at

the .001 level. A similar difference was also found

between Lahugala and the Gal Oya and Yala areas

with regard to the sizes of herds containing females

(Table 12). At Lahugala 12 out of a total of 27

observations consisted of herds of more than 25

individuals. This difference is also significant at

the .001 level.

The effect of season appears to be relatively slight

with regard to the males at Gal Oya but appears

to be somewhat important at Lahugala (Table 11).

The seasonal effects at Gal Oya for female herds are

slightly more apparent than for the males. Eight

observations of groups larger than 15 were obtained

in the Gal Oya region between the months of

November to April as opposed to only 3 for May to

Males

Herds

n n n

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 - - - -_>45

30 35 40 45

Number of individuals per group

FIGURE 44.—Frequency of observation of groups of elephants in the Gal Oya study area.
72 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

October. There is, however, little noticeable difference in the sizes of groups in the Gal Oya which

could be attributed to seasonality. Of the total 27

observations of groups, 12 groups containing more

than 26 individuals were seen between the months

of October to February at which time such large

groups were observed twice as frequently as groups

of 15 or fewer.

The distribution of group sizes is similar to that

reported for Wilpattu by Eisenberg and Lockhart

(1972). Data for Loxodonta (e.g., Laws, 1969b;

Buss and Savidge, 1966) also show a high frequency

of small groups.

To explain the observed differences in grouping

tendencies between males and females and between

the different areas requires a more detailed analysis

of the composition of the groups.

COMPOSITION OF GROUPS CONTAINING FEMALES

Of the total 120 observations of herds containing

females, 73 were of sufficient duration to distinguish

the size and sex classes of a significant number of

animals. Those groups which consisted of 15 or

more individuals always contained adults, subadults, juveniles, and infants. Groups which contained fewer than 15 individuals, on the other

hand, did not always contain members of all four

developmental classes. Table 13 shows the breakTABLE 13.—Frequency of composition for 53

small groups

HERD ACE STRUCTURE

Juveniles

Subadults

Adults

No. OF INFANTS

IN EACH STRUCTURAL

TYPE

0

1

2 ...

>2

i, 2

0

0

1 +

0

7

0

10

0

1 +

<t

5

2

13

1

1 +

6

7

1

2

16

1 +

1 +

7

5

0

14

2

16

24

9

4

53 2 2

these are the groups which contained only adult

females and infants. In the second, groups which

contained adult females plus one or more subadults

and infants; the third column contains those observations where subadults and adults were present

plus one juvenile, and the fourth column, subadults

and adults plus two or more juveniles. The rows

in this table list the number of infants present in

these different catgories. As can be seen from this

table, 3 of the 53 groups contained only adults,

i.e., sexually mature animals, and 13 contained

adults and juveniles only with no infants. On the

other hand, 20 groups contained only sexually

mature females and infants with no juveniles. A

further 10 groups contained sexually mature

females with one or more infants plus a single

juvenile and the remaining 7 groups consisted of a

mixture of mature females, 2 or more juveniles,

and one or'more infants. If these data are treated

as a 2x2 contingency table:

No infants

Infants

No juveniles

3

20

Juveniles

13

17

down of 53 groups which contained 2 to 15 individuals. This table is divided into four major

columns on the basis of the presence or absence of

subadult and juvenile individuals. In the first of

and tested using the Chi square test, the result is a

significant difference at p<0.05.

These data show that there appears to be a

division between those groups that contain juveniles but not infants (and which I shall term

"juvenile-care" units) and those groups that contain infants but no juveniles (which I shall term

"nursing" units). The following examples should

help to illustrate this difference.

These observations are taken from one particular

herd of elephants which inhabited the area of the

eastern portion of the Gal Oya National Park. This

herd was seen from March to June 1968 and again

intermittently from October 1968 through April

of 1969. For the moment I will tentatively

refer to a herd of approximately 40 individuals

from which the animals mentioned in this section

form a part. In June of 1968, the herd was observed

all together at Hatpata on three successive days

after which time they moved to an area inaccessible

by road and were not observed again until late in

October.

On the 25th of October, two adult females accompanied by a subadult male, two juvenile males,

and an infant were observed at Hatpata. One of
NUMBER 125 73

the females was readily identifiable by a cyst on her

right shoulder and the second was identifiable by

a group of cysts on her right rump. The infant

apparently belonged to the latter female as determined by the fact that he spent most of his time

with this female plus the similarity in the shape

of the ears and of the hairs at the tip of the tail.

On the 28th of October, the two adult females and

the infant were observed again at the same place.

The group was not observed again until the 7th

of November when one of the two females, that

with the cyst on the shoulder, was observed in

company of two other adult females, one of which

had an infant, the same subadult male, and a

juvenile. The other adult female from the previous

observations with her juvenile were observed feeding separately from this group with the extremely

large male-looking female which we had named

"Big Fanny." On this day it was possible to observe

the animals and it was noticed that the female

with the infant accompanying Big Fanny had a

fairly large hole in her left ear. As the result of

this she was then named "Hole Ear" in order to

distinguish her from the other female who was

termed "Cysty."

On the 8 th of November, Big Fanny, Hole Ear,

and her infant were at the same place. They were

not seen on the 9th of November but on the 10th,

the three were seen again feeding and Cysty was

out feeding with the same females she had been

with on the 7th, plus several other animals for a

total of 8. These groups were not observed again

for approximately a month but on the 7th of

December Big Fanny, Cysty, and her infant were

joined by Hole Ear.

During this period, other members of the herd

were in the area including a group containing

juveniles and a female who had only a single left

tush, a small notch in her left ear, and very long,

backward folding ears. Up to December, this female

had not been accompanied by an infant but when

observed on 16 January 1969, she was accompanied

by a very small infant which still showed traces of

the lanugo on the head and back. Both this adult

female, known as "Lefty," and her infant had the

same pattern of ear lobes including the backward

fold ^nd a similar twist of the hairs at the tip of the

tail. On 16 January, Lefty was observed with her

new infant and with a juvenile, size class 4, which

had the same ear pattern and twisting of the tail.

They were also accompanied by another adult

female. Three other adult females accompanied by

three other juveniles were present and feeding

about 150 meters away.

On the following day Lefty, her infant, and the

same juvenile were observed with Big Fanny. On

the 18th, Lefty, her infant, and Big Fanny were seen

with Cysty and her infant, while the juvenile had

joined another group consisting of three adult

females and three juveniles. One of the other juveniles had the same pattern of the ear lobes and

tail as did Lefty and her presumed daughter. The

two groups were observed feeding separately as

they emerged from the forest at approximately 1500

hours, but by 1630 hours both groups had moved

together and the two juveniles that resembled

Lefty had moved over in advance of the rest of the

group to join Lefty and her infant. On the 19th

and 20th, these animals were not observed but on

the 21st of January, the entire group was out

feeding together, including Big Fanny, Lefty, Cysty,

and Hole Ear plus several other females and

juveniles for a total of 32 in two groups, one of

23 and one of 9. On 22 January, Lefty and Hole

Ear were seen with their infants while the group

containing adults and juveniles fed in a separate

section of the bay. Big Fanny and Cysty were the

only members of the group which were not observed

on this occasion. They were not observed again

until 13 March when Big Fanny, Hole Ear with

her infant, Lefty with her infant, and Cysty with

her infant were observed with a juvenile.

Similar observations from the herd of elephants

occupying the area around the Amparai airport

also showed divisions of animals into groups of

these types. What the data from the Hatpata herd

show is that the adult females with their infants

tend to remain together in one or two groups,

while the other females form a group with the

majority of juveniles, some of which are the daughters of the females with infants. These two groups

usually feed separately, but they do come together

at feast while feeding in an open area near the

water.

Assuming that this is a general pattern for all

herds (although it cannot be proved for lack of

observation), it can be postulated that the females

within the herd form two classes of groups: females

with their nursing infants and females with juveniles. A mixture of juveniles and infants within
74 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

a single group (Table 13) occurs when the two

groups come together, such as seen on 18 January

1969, where Lefty and her new infant were joined

by Lefty's daughters.

The tendency to form two different types of

groups is caused by the propensity for females with

infants, who cannot obviously travel at any great

speed or for any long distance, to remain in association with each other and, on the other hand, for

juvenile elephants to remain with other juveniles.

Therefore, it can easily be seen how two different

types of groups can emerge, for each kind moves

at different rates, often in different directions.

Thus, for the Hatpata herd during this six

months period of observation there existed two

major subdivisions, one including Hole Ear, Lefty,

Cysty, and another female with an infant and

the other group consisting of five other adult

females plus a number of juveniles. The two major

divisions came together frequently while at Hatpata

but were usually observed separately. The only

observed transfer of a female from one type of

group to the other was the case of Lefty who

appeared and joined an infant group after the

birth of her infant some time between December

and January. Juveniles moved back and forth

between groups several times during this period,

particularly those juveniles which apparently were

the daughters of Lefty but who remained most of

the time with the females without infants and other

juveniles.

Within each of these two types of groups, however, the number and composition of individuals

varied. On some occasions Lefty was observed in

the company of Hole Ear and on others Hole Ear

was observed with Big Fanny. Although Hole Ear

was most frequently seen with Big Fanny, she was

also seen in the company of the other females with

infants. Similar transfers between members of

juvenile care groups were also observed. Thus the

structure of an elephant herd (Figure 45) may

be divided into a "nursing unit" and a "juvenile

Nursing unit Juvenile - care unit

HERD

FIGURE 45.—Hypothetical internal organization of an elephant herd.
NUMBER 125 75

care unit." Within these two groups, there is a

certain flexibility in which females may associate

together at any one time and depending upon the

size of either type of unit it may subdivide frequently into two or perhaps even three subunits.

These subunits and units remain in relatively close

contact with each other and there is potential

interchange on a short-term basis for juveniles and

on a longer term basis for adults (dependent upon

their status as lactating or nonlactating) .

The totality of the unit members is what I will

term a herd, which shares a common range. The

ranges of herds appear to overlap, sometimes extensively, but transfer of individuals between herds

does not appear to occur even when two herds

happen to be in the same area at the same time.

At the moment there are not sufficient data

available for Loxodonta to state whether a similar

phenomenon occurs in that species also. The data

of Laws and Parker (1968) would tend to indicate

that small groups consist of mothers with their

daughters—but it must be remembered that their

data are obtained by shooting and examining an

entire group, not by observing the grouping and

subgrouping tendencies over a long period of time.

Data for other ungulates show a gradation from

solitary female with infant (Diceros bicornis;

Schenkel and Schenkel-Hulliger, 1969), to family

group (Equus burchelli; Klingel, 1969), to family

group within a herd (Cervus elaphus; Darling,

1937), to a relatively amorphous herd (Connochaetes taurinus; Talbot and Talbot, 1963). This

same pattern of specialized subgrouping tendencies

has not been described for other ungulates. This

would appear to be due in part to the long developmental and growth phase of the elephant and in

part to the differences in mobility between infants

and older juveniles (and the fact that this difference

is present for long periods of time).

MEDIUM-TERM ORGANIZATION OF GROUPS

The data presented above for the Hatpata herd

showed that for periods of one to several weeks the

organization of a herd, as evidenced by the compositions of its various subgroups, tends to be somewhat flexible. As previously mentioned, there is

a definite tendency for units and subunits of a herd

to remain in fairly close proximity to one another.

Figure 46 shows the movements and approximate

area (approximately 10-20 square kilometers)

covered by the Hatpata herd during November 1968

to February 1969. The units remained in fairly

close approximation throughout the entire period

although there was some spatial separation; the

total herd was seen together on only three occasions,

although most of the members of the herd had

contact with each other by switching back and forth

between subunits.

The foraging distances and areas covered appear

to be somewhat different for infant-nursing groups

and juvenile-care groups. Unfortunately the number

of observations from which it is possible to extract

these types of data are few, but it would appear

that the nursing groups cover a smaller area within

any given unit of time than do the juvenile-care

groups as shown on Figure 46. This would appear

to be reasonable in view of the differences in

mobility between young infants and juveniles.

Since juveniles have a tendency to stay together

and move with females unaccompanied by infants

and assuming that the infant groups are less mobile

than the juvenile care units, the division of the

herd into these two unit types would appear to be

somewhat advantageous to the group; such divisions

would tend to reduce possible competition for food

between the more sedentary nursing females and

the other more mobile members of the herd.

Figure 47 shows the movements of a group of

14 elephants which constituted part of a herd

inhabiting the Ruhunu National Park from 25

July-12 August 1967. During this 18-day period

they stayed within an area of about 25 square

kilometers moving on the average less than 5

kilometers per day. This group consisted of one

nursing unit and one juvenile-care unit which appeared to remain together most of the time.

Whether they foraged separately is not known but

they certainly came together at water holes on each

day of observation. This shows that the temporal

and spatial separation of units of the herd need not

always be so marked as at Hatpata. The system is

undoubtedly subject to variation depending on

such factors as availability of water. It is possible

that the scarcity of water in Ruhunu National Park

during this period accounted for their remaining

together in the vicinity of water holes.
76

Senanayake

Samudra

12-23

Nursing unit

Juvenile-care unit

0.5 1 km

FIGURE 46.—Movements of Hatapa herd groups between November 1968 and February 1969.

Dots=nursing units; circles—juvenile care units.

LONG-TERM ORGANIZATION OF THE HERD

Figures 48 and 49 show the movements and areas

covered by two herds, the Hatpata herd and the

Amparai airport herd over periods of one year

each. As can be seen from both of these maps, each

of the herds remained in a particular area for a

period of 2 to 6 weeks, although the Hatpata herd

did remain primarily in the Hatpata region itself

for the period extending between October 1968

and April 1969. From March to June 1968, the
NUMBER 125 77

FIGURE 47.—Movements of a group of 14 elephants in Ruhunu National Park,

25 July-12 August 1967.

animals were moving fairly regularly and covered

an area of approximately 40 square kilometers

throughout this period. In June they were observed

making a long movement into an area east of

Jayanthi Wewa where they remained between July

and October. It was unfortunately not possible to

follow the group in this area during the dry season

so it is not possible to compare their movements

during this time. The movements of the Amparai

airport herd (Figue 49) were somewhat similar

in that the animals used only small areas of their

total range for periods of one to three months.

The entire Hatpata herd was seen together in

June 1968 and again in January 1969. From 10 to 13

June 1968, they were observed feeding in Hatpata

Bay on four consecutive days, in association with

another herd, which also shared this region as part

of its total range. The subsequent movements of

the Hatpata herd between the 14th to 16th of June,

indicated that the herd had gathered for the purpose of making a relatively long movement to a

geographically separate subsection of their total

range. A similar movement of a large group of

28 was recorded in October 1967. It would appear

that when herds are present in a particular area

for any length of time they tend to remain dispersed, but when they are moving from one sector

to another they gather together and move as a

group. If this is the case, then these movements

will account for the majority of the observations

of groups larger than 15 in the Gal Oya area.

The situation for the Amparai airport herd,

however, seems to be somewhat different as does

that for the herds in the region of Lahugala. The

Amparai airport herd lives in an area that is

surrounded by agriculture. When making major

movements the herd appeared to move in subgroupings, but when observed as a whole—December

1968—it gathered at one particular spot, which was

an area of abandoned paddy fields. This gathering

appeared to be more of a concentration or aggrega-
78 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Mar

— —Apr

May

—-— Jun

Jul-Oct

Nov-Apr

—» Movements, Jun 1968

FIGURE 48.-Movements of the Hatpata herd 1968-1969.

tion at a particular food source rather than a

gathering associated with movement.

It might be postulated at this point that the

reason for this difference between this herd and the

herds of the Gal Oya National Park is that the

airport herd has a relatively small and compact

home range in which the various subsectors that

the animals use are not geographically separated

by any large distance as is the case for the herds in

the Gal Oya National Park.

The movements of the Gal Oya National Park

groups are definitely seasonal. Figure 50 shows this

seasonality in range utilization for three of the

herds from which such data were obtainable. The

movement of the herds was away from the National

Park during the dry season and was correlated with

the concurrent relative unavailability of grasses

within the national park (pp. 88-90).

Similar seasonality is also observed in the appearance of herds at Lahugala Tank. Large herds were

not observed at Lahugala throughout most of the

year, small groups only being present during the

months of February to September. During the

months of November to January, however, large

groups were observed in both 1967, 1968, and

1969. The reason for these congregations of herds

at Lahugala (Table 11) would appear to be the

seasonal increase in availability of swamp grasses

which are preferred foods. During 1967-1968 three

herds were congregated in the area and during

1 mi.

Nov - Dec

Jan - Feb

Feb - Mar

Apr - May

Jun - Oct

w Tanks

1968

1969

„

M

FIGURE 49.—Movements of the Amparai Airport herd

1968-1969.

FIGURE 50.—Seasonal ranges of three herds (Hatpata, Baduluwela and Talawa) in the Gal Oya study area. Dry season

ranges are shaded. Note overlap during wet season.
NUMBER 125 79

1968-1969 five herds were at the tank. These herds

always entered the tank from the forest as a complete unit, not as subunits. On eight occasions when

two or more herds were present, each herd maintained its integrity without transfer of individuals.

Figure 51 shows two herds over a period of approximately one hour, during which time they were feeding and moving. These photographs show how. the

herds approached each other, fed in close proximity for a short period of time, then began to

move off in different directions. This was particularly noticeable on 14 November 1967 when

two herds were under observation at Kitulana

Tank. The herds maintained relative integrity over

a very large area of the tank, covering approximately 40 percent of the tank's breadth. At 1710

hours, however, the animals were alarmed by the

appearance of a jeep. Upon sensing its presence,

they clumped and ran off toward the forest reforming into the same two tight formations in which

they had originally emerged from the forest.

From all of the above observations, the following

conclusions can be drawn regarding the long-term

organization of herds. A herd, which generally

consists of between 15 and 40 individuals, tends to

remain distinct from all other herds which may

occur in the same general area. The herd does not,

however, remain together as a whole throughout

any long period of time but tends to forage as

units as outlined above. These units forage over

relatively small areas of the total range of the herd

throughout periods of varying lengths but there

does not appear to be any strict division of areas of

feeding between the units and subunits. Rather the

differences are temporal and depend upon the

movement rates of the animals making up any given

unit. There is, however, a spatial distinction which

can be made over a period of a year or more and

this appears to be seasonally determined. Thus a

particular herd uses a portion of its range during

the wet season and another portion during the dry

season. These then can be termed rainy-season

range and dry-season range, the total of which adds

up to the herd range. This could be likened to the

concept of home range as applied to other animals,

although it might be more accurate in this case to

consider two seasonal home ranges for the majority

of herds.

Ranges of herds overlap to a greater or lesser

degree. There does not appear to be any strict

seasonality to the tendency for home ranges to

overlap; but it can be shown from the above data

that the home ranges of herds in the Gal Oya

National Park area tend to overlap more extensively

during the rainy season than during the dry season

(Figure 50). A similar trend appears at Lahugala.

(For the potential factors which may cause the

tendency to overlap home ranges see pages 88, 92.)

Although it is impossible with the data available

to make a definite statement regarding the separation of elephant populations, Figure 22 shows the

approximate total ranges of the herds in the area

of the Eastern Province included in this study.

From this, it would appear that two relatively

distinct populations occur, one around the Gal Oya

National Park and the Amparai area, and a second

around the Lahugala-Ruhunu National Park area.

The herd around the Amparai airport is relatively

small and its distinctiveness may be due not so

much to the traditional movements of the animals

themselves but to the fact that they have become

relatively isolated due to expansion of agriculture

in this area. The two populations are relatively

large, being an estimated 260—300 for the Gal Oya

National Park and 150 for the Lahugala area (see

pp. 34-36). The population of elephants around the

Lahugala area apparently draws its member herds

from the areas to the north of Lahugala and to the

south, perhaps as far south as the Kumbukkan Oya.

Unfortunately, I have few data for the animals in

the region of the Kumbukkan Oya but the apparent

movements of these animals indicates that those

from Block 4 of Ruhunu National Park move

northward during the latter part of the dry season

and probably contribute to the herds seen around

Lahugala during November. The movement patterns of elephants in Blocks 1, 2, and 3 of Ruhunu

National Park—distinct from those of Block 4—tend

to be more towards the west.

Similar distinct seasonal ranges were documented

by Eisenberg and Lockhart (1972) for Wilpattu

National Park indicating that this might be a

general phenomenon for all elephant populations

in at least the drier parts of Ceylon.

Singh (1969), who has studied the elephant in

Uttar Pradesh, India, states that some herds, especially those in the eastern and western regions of

his study area, showed distinct seasonal movements.
80 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 51.—TWO herds feeding in Lahugala Tank, 15 November, 1967.
NUMBER 125 81

Others, such as the elephants in the Kalagarh region

show little seasonal movement—a difference he

attributes to the constant availability of food and

water in this latter area.

Khan (1967) followed a herd of nine elephants

over a period of 5 years in Perak, Malaysia. Although these animals did range over distances of

10-15 kilometers or more, there was no apparent

regular seasonality to their movements.

The literature on the African elephant contains

many references to long migrations of a seasonal

nature (for example Sikes, 1971:105-107) but the

data presented by Laws (1969b) would indicate

that the seasonal shifts in home range are not so

great but are consistent with the data obtained

from Ceylon.

THE ROLE OF THE MALE

The majority of males that were observed not

in association with females were single individuals

(see page 70). Those data, however, do not

take into account the males that were observed

in association with herds (Table 14). Of the 73

counts made of herds in which sexes could be

determined accurately 44 were not accompanied

by males. The remaining 29 herds (or 40%) were

accompanied by at least one male. The majority of

such herds were accompanied by a single male,

with three accompanied by two males, three accompanied by three males, and one each accompanied by 4 to 8 males. If these 29 observations

of males associated with herds are added to the

other 99 of males not associated with herds, it

TABLE 14.—Number of males in association with

herds

Number of males

with herd

Number of

herds

0

1

2

3

4

5

6

7

8

>8

Total

44

18

3

3

would tend to show that males are on the average

in association with herds for approximately 25

to 30 percent of the time.

Table 15 shows the observations of males seen

associating with the Hatpata herd (or parts of that

herd) over a 5-month period. As these data show,

no given male associates with the herd for a period

longer than a few days. Indeed, the fact that any

number of males were present only during January

would seem to indicate the likelihood that one or

more females were in estrus at that time.

TABLE 15.—Males associating with the Hatpata

herd, November 1968-March 1969

Number of females Number

Date and young in group of males Identity of males

1968

7 Nov.

8 Nov.

10 Nov.

7 Dec.

8 Dec.

1969

15 Jan.

16 Jan.

17 Jan.

18 Jan.

21 Jan.

22 Jan.

8 Mar.

12 Mar.

13 Mar.

9

3

11

8

5

7

10

13

10

6

20

23

3

3

8

0

0

0

1

0

1

2

I

5

2

3

5

0

0

0

YA-1

YA-1

YA-1 YA-2

A-3

A-4 A-2 YA-1

YA-2 YA-3

A-3 A-5

A-3 YA-1

1 unidentified

A-3 A-l YA-1

2 unidentified

0

73

A=adult, YA=young adult.

Figure 52 shows a superposition of the approximate home ranges of four adult males known to

inhabit the Hatpata area on the home range of the

Hatpata herd. It can be seen from this that the

home ranges of males tend to be somewhat smaller

than the home ranges of herds. These are, in some

cases, smaller than a temporary monthly range of

the herd. Not all males, however, show this particular sedentary pattern. The examples in Figure

52 were chosen specifically to show this pattern. A

second pattern was recorded for two males which

were marked during an experiment on tranquilization (see Gray and Nettasinghe, 1970) as well as
82 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

some others which had been identified from their

own physical pecularities. The patterns for the two

marked males (Figure 53), demonstrate that these

individuals tend to move in a manner similar to

the herds, in that they spend two to several days

in one locality, often covering an area of less than

1 square kilometer, then move to another area

where the same pattern is repeated. Male No. 2 in

particular was remarkably sedentary when in any

one area but made fairly extensive movements on

three different occasions. He was seen feeding primarily on Mimosa pudica and his movements from

one section to another were, at least, unidirectional.

He did not return to an area that he had just left

for when he moved on the Mimosa from that area

had been almost totally uprooted and eaten.

The home ranges of males overlap quite extensively and, in many cases completely. Correlated

with this, there is no evidence of male behavior

that could be described as territorial. On the

other hand, it would appear that there is a great

amount of tolerance between males with the possible exception of periods when a female is in

estrus. Aggression between males was observed once

when a female was definitely known to be in estrus

during November of 1967, as reported by Eisenberg,

McKay, and Jainudeen (1971), and on three other

occasions where aggressive behavior was seen between males in association with a herd. In these

three latter instances, the behavior of the males

towards the females indicated that there might be

a female in estrus in the group, although it was not

possible to determine this positively. It would

appear that the males remain relatively dispersed,

at least throughout most of the year, and that they

tend to remain restricted to relatively small home

ranges. Throughout most of this longer period, they

are solitary or associate temporarily in male groups.

\

1 km

FIGURE 52.—Home ranges of four adult males superimposed

on the total annual range of the Hatpata herd.

1 mi.

FIGURE 53.—Movements of two marked males (Nos. 2 and 3)

during October and November, 1967. Circles represent No. 2;

squares, No. 3. The largest circle and square indicate the site

of marking; the smaller symbols, centers of activity on subsequent days. The number of days spent in any one place is

indicated by the number beside the symbol.
NUMBER 125 83

Male groups were observed relatively rarely in

the Gal Oya National Park itself, but on those

occasions where groups were observed they consisted of animals which had overlapping or at least

adjoining home ranges. A similar phenomenon undoubtedly occurs at Lahugala Tank where the tank

apparently provides a focal point in the home

ranges of a number of adult males. The fact that

the lush growth of grass in Lahugala Tank provides

a nutritional attraction to males would appear to

facilitate the formation of groups in this area, as

there is a relatively high probability of more than

one animal using that particular portion of its home

range at any one time. This then would appear to

account for the higher frequency of male groups

observed at Lahugala as opposed to those observed

in the Gal Oya and Ruhunu National Park areas.

Even at Lahugala, however, the groupings of males

are temporary. Figure 54 shows the composition of

male groups observed during March 1967. It can

be seen from these observations that the members

of any particular group on any particular day vary

considerably.

Although there is no apparent stability in the

Mar. 6 A 2 A3 SA4

A

9 SA12 SA13

8 A2 A 9 A17 SA4 SA6 SA13 SA14

| A 2

| A 9 SA4] |A17 SA6 | | SA13 SA14]

10 A 2 A21 SA6 SA13 SA14 A1 9 SA2 Q |

11 A2 A17 A2 2 SA4 SA6 SA1 4 |

12 An A1 7 A2 2 SA6 SA13 SA2 Q |

13 A 2 SA4

S A 6 |

14 SA12] |A 2 2 SA4 SA6 SA13 SA14

FIGURE 54.—Composition of male groups at Lahugala Tank over a period of eight days in

March 1967. A—adult; SA—subadult.
84 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

composition of any particular male group, temporary organization would be dependent upon the

relative dominance of the members. It is not possible to say from the data available whether there

is any strict hierarchy between the animals but

observations of aggressive behavior between males

in groups (pages 62-65) would indicate that there

is a recognized relationship between individual

males. Hendricks (1971:116) found a similar situation among male groups in Loxodonta where

group composition was constantly changing but

individuals could be categorized according to their

relative dominance rank. Unfortunately when one

takes a short time slice out of the lives of these

animals, it is impossible to know their previous

A 2

social history. It would appear, however, that adult

males of perhaps 30 or more years of age probably

have known each other for a large percentage of

that time and a dominance relationship may have

been set up several years prior to any observation.

This is a reasonable assumption in the light of

observations at Lahugala which show a greater

frequency of social interaction between subadult

males than between fully adult males, especially

with regard to the occurrence of play-fighting (page

65). Figure 55 indicates the amounts of time

spent in play-fighting by four subadult and five

adult males over a 6-day period at Lahugala in

March 1967.

A similar dominance phenomenon appears to

A 3

A 9

A 11

A 17

6

7

8

9

10

11

6

7

8

9

10

11

SA

14

08 10 12 14 16 08

TIM E

10 12 14 16

FIGURE 55.—Amounts of time spent in play-fighting by four subadult (SA) and five adult (A)

males at Lahugala over a period of six days (March 1967). Lines indicate time of day (in

hours) animals were observed in the tank. Black bars indicate time spent in play-fighting.
NUMBER 125 85

occur when males are in association with herds. For

example, on 15 November 1967 a large male, which

had been in association with a herd containing

one or possibly two estrous females, was seen to

drive a subadult male away from the proximity of

those females on three occasions within a period

of half an hour. A similar phenomenon was observed in June 1968 with the Hatpata herd as they

were feeding at Hatpata and at Kossapola where

several males were in association with the herd but

one particular male was seen to interact with and

chase another male which attempted to approach

the herd. Also, observations of the Amparai herd

on 4 December 1968 included a sequence during

which a large adult male and three smaller adult

males were in relatively close association with the

herd. The smaller males were feeding about 30

meters away from the larger adult when two of

the smaller males began to fight. As the fight progressed, the two began to move closer to the large

adult. The large adult did not approach the two

who were fighting but as these latter two came

closer to the adult male, they broke from fighting,

both moved over toward him, and initiated mutual

trunk to head contact with the large adult. After

the brief contact, the males all went back to feeding.

Males appear to leave the herd and become

solitary at about the time of puberty. Juvenile

males of size classes 5 to 6 are frequently seen

feeding at greater distances from the rest of the

group, often moving in advance of the main herd.

On three occasions at Lahugala during November

1967, the first members of a herd to emerge from

the forest and enter the tank were subadult or large

juvenile males. As they get older, they appear to

extend these wanderings from the herd until at

some point they become solitary. Unfortunately

during the period of this study, no instance was

actually observed where a known juvenile left a

herd.

Subadult males appear regularly at Lahugala.

On a few occasions these individuals would remain

in the vicinity for several days, but the majority

(such as two young tuskers observed in March 1967

and a third tusker seen in July 1967) were seen on

only one or two occasions, then never again. It

seems probable that these were transient individuals

which had not yet settled in a particular home

range. For adult males, on the other hand, there

were more residents than transients as shown by

the following data from 1967:

Adult

Subadult

Resident

18-20

2

Transient

2-5

6-8

The patterns of distribution shown by males

indicate that although there is no overt territoriality, there is an effective spacing based on the

relative restriction of individual males to small

home ranges. There does appear, however, to be a

certain amount of dispersal on the part of the

males which although not definite may be greater

for the younger animals. If there is extensive

dispersal on the part of young males, which only

studies over several years would be able to prove,

this would enhance the degree of potential outbreeding for any given population. As the herds

of females tend to be relatively stationary, the

potentiality for outbreeding will also be enhanced

by the fact that a herd in any given period of time

moves over an area which includes the home ranges

of several adult males. It is possible, therefore, for

a herd whose constituent females apparently come

into estrus at different times to be exposed to a

large number of males, a significant proportion of

which will be animals not related to the females.

Movement Patterns and Habitat Utilization

THE HOME RANGE

The general pattern of movement by elephants

within the home range was discussed in an earlier

section but there are several aspects of the use of

the home range which deserve more attention.

These concern various fixed points which occur

within the home range of any herd.

Water

One of the most important environmental factors

for the elephant is the presence of free water. Each

of the ranges of the herds contains at least one river

system and generally one or more small tanks or

a portion of a large irrigation reservoir (Figure 50) .

Throughout the Gal Oya—Lahugala area, rivers and

streams are abundant, and within the past 25 years

many tanks have been constructed, impounding

large areas of water. Water distribution in Gal Oya
86 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

National Park differs from the other two parks in

Ceylon. In Wilpattu National Park, as reported in

Eisenberg and Lockhart (1972), the streams and

rivers tend to be somewhat localized and a large

portion of the park is characterized by vertical

drainage rather than lateral drainage, and in this

area occur a large number of circular water holes

known as villus. In Ruhunu National Park, the

rivers as in Wilpattu are widely separated and with

relatively few tributaries; villus are absent. There

are several lagoons along the coastline of Ruhunu

National Park which contain water of varying

salinity and there are a large number of water holes,

some permanent, some dependent upon seasonal

rainfall, distributed throughout the park.

The areas used during any given monthly period

by the herd at Hatpata were always close to a

source of water (Figure 48). For the greater part

of the year, this source of water was the Senanayake

Samudra. A similar pattern is shown for the Amparai airport herd where no matter what section

of the home range they were using at a particular

time, they are relatively close to one of the several

tanks in the area or to the irrigation channel which

passes through to the north of their range. Elephants appear to move towards water and to drink

and bathe once a day; as such they cannot afford

to move very great distances away from water

during times of feeding. Eisenberg and Lockhart

(1972) have shown that the herds in the Wilpattu

National Park area tend to move from one villu

to another. A similar pattern is shown in Ruhunu

National Park (Figure 47) where the herd moved

from water hole to water hole. In some cases, it

moved in a direct line; in other instances it moved

over a large front through the forested areas. As

such water holes are not abundant in the Gal Oya

area, this particular type of movement pattern

was not observed in that region. Elephants in the

Gal Oya region tend to move from one stream

valley to another and frequently show a pattern of

moving along the streams, even along rivers, or

in the case of the lower Gal Oya valley, irrigation

channels.

Elephants generally do not drink at any point

along the stream or channel but have particular

drinking spots which they visit regularly, as well as

particular crossing points. One particularly heavily

FIGURE 56.—Heavily used crossing point on left bank channel near Amparai airport.
NUMBER 125 87

used crossing point of the left bank channel is

3 kilometers south of the Amparai airport where

the banks of the channel have been broken down

by continued use by the elephants (Figure 56).

Trails

As elephants tend to move to and from particular

points in their home range rather than over a broad

area, there results a series of trails which undoubtedly have been built up over the years by successive

generations of elephants. In grassy areas, such as the

Talawa savannas of the western Gal Oya National

Park, the trails occur as areas of ground which have

been denuded of vegetation. Sometimes the trail

is cut into the surface of the soil as much as 5-7

centimeters. In forested areas, the trails, besides

being characterized by a disturbance or absence of

the ground vegetation, are also characterized by the

lack of undergrowth growing around the trail

itself, as it would appear that elephants and other

ungulates moving to and fro along these trails tend

to feed while moving, thereby removing much of

the new growth of saplings, etc.

"Rest Rooms"

When walking along one of the elephant trails, one

occasionally encounters an area of 50 to 100 square

meters where the ground vegetation is completely

lacking and the shrubs have been uprooted or

broken down. Occasionally branches may also be

pulled from several trees in the area. This tends to

give such an area an open room-like nature (Figure

57). These "rooms" often tend to occur at the intersection of two trails and are found widely spaced

FIGURE 57.—Room-like clearing used for resting.
88 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

around the Gal Oya Natioanl Park, being particularly prevalent around the periphery of Lahugala

Tank. On two occasions, elephants were actually

observed standing and resting in one of these rooms

where there is usually a large number of relatively

fresh dung piles. It would appear that they are

used primarily for resting in that they provide an

area relatively clear of vegetation which also provides shade from the direct radiation of the sun.

Rubbing Trees

Around any particular water hole or tank or portion

of stream that is used regularly for bathing by

elephants, there can be found one or more trees

that are used by the animals for rubbing (p. 48).

Buffalo and boar also use these trees, but the

identity of the species using the tree can easily be

told from the height of the mark. Around Lahugala

Tank, for example, 33 trees used by elephants were

found in one 700 meter segment of shoreline.

Some of these trees were within the forest adjacent

to the tank but most were either at the edge or

solitary trees away from the edge of the forest

(Figure 30). Most of the trees used for rubbing are

relatively large. In fact, of the 33 examined at Lahugala, 6 had a diameter of greater than 75 cm.

10 of 50 to 75 cm, 16 of 25 to 50 cm, and only one

had a diameter of less than 25 cm. As was also

mentioned earlier, these trees are often marked

with the tusks or tushes as well as being used for

rubbing and of the 33 examined at Lahugala, 24

were rubbed only, 5 were marked with the tusks

only, and 4 were used for both purposes.

The importance of such fixed points in the home

ranges of animals has been discussed in detail by

Hediger (1951) and further discussion of the primary function of each type of fixed point is not

necessary here. There is, however, a secondary

function which I believe to be quite important for

the elephant. These fixed points facilitate regrouping by members of a herd who have been foraging

alone or as small units. Water holes appear to be

especially important in this regard. With few exceptions, whenever various subgroups of a herd

were observed coming together this took place in

the vicinity of a frequently used watering place.

SEASONALITY OF MOVEMENTS

Figure 50 shows the home ranges of three of the

herds in the Gal Oya area for which details were

known of their seasonal movements during 1968.

As mentioned earlier (page 26), large areas of the

savanna land in the western portion of the national

park and surrounding areas were burned during

June and July of 1968. Up to the beginning of

July of that year, the southwestern herd was resident in the northern portion of its range (Figure

50). The Talawa in that area was burned between

the 5th and 10th of July of that year and following

which, tracks of elephants known to be there were

found heading towards the southwest. Later in the

month, the herd was located in the vicinity of

Baduluwela further upstream along the Sellaka

Oya. A portion of this herd or more likely the herd

to the north moved during this same period along

the Gal Oya down toward the region of Kotabowa.

The movement of the Hatpata herds, which took

place in June, has been described earlier (Figure

48) and was from the area of Hatpata towards the

area east of Jayanthi Wewa. Similar seasonal movement patterns took place in 1969, but earlier than

in 1968, as conditions of drought began in March

and April and continued throughout the normal

dry season due to the failure of the rains which

normally fall during the spring intermonsoonal

period.

In each of these movements, the relative amounts

of available water in either half of the home range

were approximately equivalent; thus, availability

of water can be effectively eliminated as a potential

factor in causing these movements. For the herds

which reside in the western portion of the national

park and to a certain extent for the herd around

the Amparai airport, it is quite likely that the

major factor influencing the movement was the

availability of grass. In other words, after the

burning of extensive areas of grassland in parts of

their ranges, they moved to a separate area where

fires had not been so extensive; in the case of the

one herd in the southwest portion of the national

park, it moved to an area which was primarily

forest.

The movements of the Hatpata herd can also

be explained by a change in the abundance of grass

as a food. During the growing season of early

1968, the banks of the Senanayake Samudra in the

area of Hatpata and Kossapola contained large

areas of grass (Figure 58a). By June, however, the
NUMBER 125 89

FIGURE 58.—Grassland on the banks of the Senanayake Samudra: top, during growing season;

bottom, after cropping by buffalo and scarification by elephants.
90

grass over this entire area had been cropped extremely short by herds of buffalo which are grazed

in this area. As a result the elephants in order to

feed had to collect the remaining grass by scarifying

with the forefeet. This resulted in large bare areas

(Figure 586). Grass is a very important constituent

of the elephant's diet. Although the grass was not

unavailable in quantity, the relative scarcity of the

grass may have been one factor in determining the

movement of elephants out of this area.

Seasonal movements in Wilpattu National Park

(Eisenberg and Lockhart, 1972) appear to be influenced by availability of both food (wet-season

movements to the large grassy villus in the West

Sanctuary) and water (dry-season movements to the

permanent water in the center of the park).

The factors causing seasonal movements by

African elephants appear to include both food and

water. Buss (1961) mentioned concentrations of

elephants around Lake Albert and the Victoria

Nile during the dry season. He also mentions

animals moving to forested areas but concludes this

is primarily for shade. More recent data (Wing and

Buss, 1970) have shown that the forest areas are

extremely important as a source of food. Buechner,

et al. (1963), working in the same area, considered

that the most important factor in elephant movements was the availability of food, particularly

grass. As the availability of grass is affected in turn

by the season (and by fires during the dry season),

and as the weather is seldom the same from one

year to the next, it is not surprising that there is

no strict annual cycle. There is rather a varying

cycle depending on the weather and grass conditions in any one year. Thus there is a great

similarity between the types of movement patterns

shown by both species, the main feature of which

is the ability of both to move long distances when

necessary. That this response appears to be triggered

by proximate factors rather than an annual (photoperiod or whatever) cycle is particularly adapted to

the variable climates in which they live.

USE OF HABITAT TYPES

Table 16 shows the total numbers of hours of

observations for both males and herds in the Gal

Oya area classified according to the habitat type in

which the animals were seen. A large percentage

of the observations were made in grassland or other

SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

TABLE 16.—Observations of elephants in Gal Oya

habitat types

Habitat type

Forest

Forest (chena)

Forest-scrub

Scrub

Savanna woodland

Shrub savanna

Grassland

Water

Agricultural land

Forest/Grassland ecotone

Total

Total hours

Males

18.0

0

7.0

9.5

3.0

0.5

50.5

6.0

2.0

15.5

112.0

of observation

Female herds

8.0

0.5

0

0

10.0

14.0

35.5

1.0

0

35.5

104.5

open habitats such as the ecotone between forest

and grassland, or savanna lands. While these data

do not indicate an accurate representation of the

total time spent by elephants in different habitats,

they do point out a few interesting facts.

First, elephants, both males and herds, tend to

spend a relatively large amount of time at interfaces between forest and grassland. There are two

possible explanations for this. First, they are able

to feed on grasses without venturing too far from

the relative safety of a forested area and, second, by

moving and feeding in an ecotone area, they have

available a greater variety of potential food plants

during any given feeding period than they would

were they in the forest or further out into the

grassland. Another interesting fact to come out

of this is that elephants, especially herds, are seldom

encountered in agricultural land during the daytime. In the area around the Gal Oya National

Park their depredations on paddy lands and on

sugarcane generally take place at night (see

pages 102-103).

Figure 59 shows the times of observations of

elephants feeding on grasses or shrubs in half-hour

intervals throughout the day. The peaks of feeding

show the same patterns as the general times of

activity for both males and female herds (Figure

35) although the morning peaks for both males

and females for feeding on grasses are earlier than

those for feeding on shrubs. The explanation for

this would appear to be that elephants are more

liable to be found in open areas in the cooler hours

of the early morning than the later hours around

noon.
NUMBER 125 91

Min

45

4 0

35

3 0

2 5 -

2 0

15-

10-

5 -

0

5 -

1CH

15

Male

Female

Shrubs

0500 0700 0900 1100 1300 1500 1700 1900

Half-hour intervals

FIGURE 59.—Times at which elephants were observed feeding on grasses and shrubs in Gal Oya.
92 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

Table 17 shows the results for observations of

elephants in Ruhunu National Park during 1967,

classified according to different habitat types. As

in Gal Oya, observations were more frequent in

open habitats than in closed ones. Lahugala Tank

(Figure 38) was more heavily used during the

growing season than during the dry season. Since

the major difference between the two seasons in the

habitat is the lush growth of grass, which follows

the onset of the northeast monsoon in November,

it is obvious that the major attraction of Lahugala

Tank for the elephants is the abundant supply of

food. Similarly concentrated food supplies were

found in an area of abandoned paddy land immediately south of the Amparai airport and during

November and December of 1968, the entire herd

from that area congregated in this one spot to feed

for a period of three weeks, coming in every evening to the paddy.

TABLE 17.—Number of elephants observed in various

habitats of Ruhunu National Park, 1967

Habitat type

Riparian forest

Medium-stature forest

Scrub with emergents

Scrub

Savanna ...

Grassland

Dunes

Water (tank, lagoon)

Males

12

2

26

3

31

32

0

10

Herds

0

0

6

4

2

7

0

3

Total

12

2

32

7

33

39

0

13

The important fact to keep in mind is that the

elephants have a variety of vegetation types within

this region of Ceylon and that they make use of

all of them. Wing and Buss (1970) have reviewed

the literature concerning the food habits and

habitat utilization of Loxodonta and have concluded that the optimum habitat for that species

is one which contains an interspersion of forest

and grassland or savanna types. Their own study

area contained 60 percent forest and 40 percent

grassland—a ratio they considered to be close to the

ideal. They (Wing and Buss, 1970:66) concluded

that the declines noted in some East African elephant populations (e.g., Buss and Savidge, 1966;

Laws and Parker, 1968) can be attributed to an

imbalance in this ratio: "an increase in grassland

probably favored the elephant population until

browse reduction reached a threshold below which

elephants ate grass in excess of their optimal

nutritional requirements." They also state that

under the optimal conditions, such as those present

in their own study area, the elephant populations

appear to be in equilibrium with their environment and no significant destruction of woody vegetation (as reported by Laws, 1970) occurs.

Thus it would appear that existing conditions

in the Gal Oya region are very similar to those

judged to be optimal in Africa. (For further

similarities between my own data and those of

Wing and Buss (1970), see page 96).

FOOD PLANTS

Table 18 lists the plants occurring in the Gal Oya

area which were known to be used for food by the

elephants (nomenclature after Abeywickrama,

1959). This is an extremely long list and includes a

relatively large proportion of the total plants found

in this area. Grasses were used extensively; the

most important being Brachiaria, Cymbopogon,

Cynodon, Eleusine, and Imperata. Most species of

the genus Cyperus were not used but a relatively

large-sized one abundant at Lahugala Tank was

eaten extensively.

Bananas (Musa), paddy (Oryza), and sugarcane

(Saccharum) were the three cultivated crops fed

upon most frequently. The bananas and paddy

are planted widely throughout the area, but the

sugar is concentrated in one large plantation south

of Amparai.

Of herbaceous plants other than grasses the most

important is Ipomoea (Convolvulaceae). This genus

includes several species which grow as herbaceous

vines in the dry zone of Ceylon. Ipomoea is

especially abundant in abandoned chenas, at

ectones between forest and grassland and particularly in the drier areas of the banks of the

Senanayake Samudra and other man-made tanks.

Mimosa pndica, which is also heavily used by the

elephant, is also abundant in these disturbed

habitats.

Woody vines or lianas, such as Hugonia and

Cissus, are occasionally eaten. With these plants

the elephants generally pull down a large section

of vine and eat the bark and stems rather than the

leaves. The bark of Feronia limonia is frequently

eaten during the dry season; that of Pterospermum,

only occasionally. Calamus, a small shrub which

grows along the banks of the Gal Oya, of which
NUMBER 125 93

Family

HERBACEOUS

Gramineae

Cyperaceae

Convolvulaceae

Leguminoseae

VINES

Linaceae

Loranthaceae

Vitaceae

TREES AND SHRUBS

Rutaceae

Palmaceae

Musaceae

Sterculiaceae

TREES AND SHRUBS

Ulmaceae

Moraceae

Anonaceae

Lauraceae

Cappardiaceae

Leguminoseae

TABLE 18.—Plants eaten by elephants in the Gal

Species

Digitaria sp.

Brachiaria sp.

Panicum repens

Oryza perennis

Oryxa sativa

Imperata cylindrica

Saccharum officinarum

Ischaemum sp.

Cymbopogon confertiflorus

Themeda sp.

Cynodon dactylon

Eleusine indica

Eragrostis sp.

Paspalum sp.

Cyperus sp.

Ipomoea sp.

Mimosa pudica

Crotalaria sp.

Hugonia mystax

Loranthus sp.

Cissus quadrangutaris

(Bark, roots, etc.)

Feronia limonia (bark)

Calamus sp. (roots)

Musa paradisiaca (stem)

Pterospermum canescens (bark)

(Leaves and smaller stems)

Celtis cinnamotnea

Fiscus spp.

Polyalthia longifolia

Polyalthia persicifolia

Alseodaphne semecarpifolia

Crataeva regiliosa

Capparis grandis

Butea monosperma

Pterocarpus marsupium

Cassia fistula

Cassia roxburghii

Bauhinia tomentosa

Bauhinia racemosa

Dichrostachys cinerea

Acacia eburnea

Acacia plantfrons

Family

Erythroxylaceae

Rutaceae

Meliaceae

E u phor biaceae

Anacardiaceae

Celastraceae

Sapindaceae

Rhamnaceae

Tiliaceae

Malvaceae

Sterculiaceae

Flacourtiaceae

Datiscaceae

Lecythidaceae

Combretaceae

Myrtaceae

Melastomaceae

Sapotaceae

Ebenaceae

Longaniaceae

Apocynaceae

Boraginaceae

Verbenaceae

Rubiaceae

Oya region.

Species

Erythroxylon moonii

Glycosmis pentaphylla

Pleiospermium alatum

Aglaia roxburghiana

Chukrasia velutina

Phyllanthus emblica

Drypetes sepiarta

Mischodon zeylanicus

Bridelia retusa

Macaranga peltata

Dimorphocalyx glabellus

Mangifera zeylanica

Elaeodendron glaucum

Lepisanthes trichocarpa

Glenniea unijuga

Euphoria longana

Zizyphus oenoplia

Zizyphus xylopyrus

Pi tyrant he verrucosa

Berrya cordifolia

Grexvia polygama

Grewia tiliaefolia

Thespesia populnea

Helicteres isora

Pterospermum canescens

Hydnocarpus venenata

Tetrameles nudiflora

Careya arborea

Terminalia chebula

Anogeissus latifolia

Syzygium aromaticum

Syzygium cumini

Eugenia sp.

Memecylon sp.

Mimusops elengi

Manilkara hexandra

Maba buxifolia

Diospyros ovalifolia

Diospyros oocarpa

Diospyros malabarica

Strychnos nux-vomica

Strychnos potatorum

Carissa spinarum

Cordia domestica

Premna lati folia

Randia dumetorum

lxora parvifolia

Morinda tinctoria

only the roots and lower stems are eaten is occasionally uprooted. In areas such as the lower

Mahaweli Ganga basin, where this palm is more

abundant it is heavily used (Nettasinghe, pers.

comm.). When elephants feed on the banana or

plantain (Musa), they generally discard the leaves

and outer portions of the stem, eating only the

central part.

Several of the plants eaten by elephants (Acacia,

etc.) have large spines. These may be broken before

ingestion but are not removed from the stem. From

a sample of 33 boluses collected in Ruhunu Na-
94 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

tional Park during August 1967, 19 contained large

numbers of Acacia eburnia spines, indicating heavy

usage of this species.

The diet of the elephant includes a large proportion of twig and leaf material gathered from shrubs

and smaller trees. Table 18 includes more than 60

species belonging to 30 families. This list is not

intended to be a complete catalog of the plants

used, by the elephant, even in this region. Undoubtedly, a closer examination would reveal that

elephants consume at least small amounts of most

of the plants found in the area. The significant

point is that the elephant is not a restricted feeder.

It is capable of using many if not most of the tree

species available to it. This does not imply that all

plant species are eaten with equal frequency.

Certain species, such as Cassia fistula, Bauhinia

racemosa, Euphoria longana, Helicteres isora, are

heavily used wherever they are abundant.

Fruits are occasionally eaten but, except in one

instance when an animal was observed eating

Tamarind (Tamarindus indica) fruits, these were

generally consumed along with the leaves and twigs

of the plant. It would thus appear that the majority

of fruits are eaten accidentally in this way.

Table 19 shows the caloric densities determined

for some of the more important food plants. The

TABLE 19.—Caloric densities of selected food plants

Part used

Leaves

Leaves and

Stem

Stem

Bark

Species

Celtis cinnamomea

Polyalthia persicifolia

Polyalthia sp.

Drypetes sepiaria

Berrya cordifolia

Grewia tiliaefolia

Hydnocarpus venenata

Careya arborea

Diospyros oocarpa

Ixora parvifolia

Digitaria sp

Cymbopogon confertiflorus

new

green

dry

Cynodon dactylon

Eleusine indica

Eragostis sp.

Carex sp.

Loranthus sp.

Pterospermum canescens

Kgcal/gm

4.60

4.85

455

3.84

4.S0

4.10

3.79

3.88

4.29

4.46

3.01

3.38

3.87

3.75

334

359

4.18

2.96

4.02

3.74

majority of these plants have caloric densities which

vary between 3—4 Kgcal/gm. The grasses generally

have a lower caloric value than the shrubs. This

difference between caloric values of grasses and

shrubs is probably due to the differences in chemical constituents (fats and proteins). These factors

will be considered in more detail elsewhere (McKay,

Kalpage, and Jayasinghe, n.d.).

Chemical compositions were determined for

eight species (4 grasses and 4 shrubs) at bimonthly

intervals during 1969. The compositions of four

grass species showed little variation throughout the

year but Cynodon and Brachiaria had a relatively

higher proportion of nitrogen-free extract to fiber

than did Imperata and Cymbopogon. All of the

shrubs sampled had a consistently higher proportion of protein in their leaves than did the grasses.

Four other species were examined, but not at

regular intervals. Three (Mimosa pudica, Bauhinia

racemosa, and Phyllanthus emblica) were legumes

and contained a higher (2X) proportion of "crude

protein." This figure was undoubtedly biased by

the non-protein nitrogen present in members of this

family. The fourth, Eleusine indica, a grass, resembled Cynodon in its composition. For further

discussion of the differences in chemical composition of these plants the reader is referred to McKay,

Kalpage, and Jayasinghe (n.d.).

FEEDING BEHAVIOR

An elephant, when feeding, seldom spends much

time feeding on one particular plant species. The

major exceptions to this are instances where the

animals come out into the short grass zone of the

banks of the Senanayake Samudra or other irrigation works in the area, which consists primarily of

Cynodon, Brachiaria, and Eleusine. The other

major exception noted to this was the animal

marked as No. 2 (p. 82), who spent long periods

of time feeding on Mimosa pudica. Otherwise, the

general feeding pattern is to alternate between two

or more different types of food (Figure 41). Table

20 shows a typical set of observations recorded from

Ruhunu National Park of the time spent by elephants feeding on different types of food. These

were recorded during 1967 and are expressed in

animal minutes. As can be seen from this, the

greatest amount of time spent was on feeding on

short grasses including leaves, stems and roots. The
NUMBER 125 95

TABLE 20.—Time spent feeding on various types of

vegetation, Ruhun.u National Park, 1967

Food type

Long grasses

Short grasses

Leaves/twigs

Whole twigs

Fruits

Total .

AprilMay

62

1410

29

10

0

1511

JuneJuly

28

44

12

192

10

286

JulyAugust

18

1110

40

56

1

1228

Total

108

2594

81

258

11

3025

next highest category was feeding on branches of

trees or shrubs followed by feeding on long grasses.

Figure 59 shows the amounts of time spent by

elephants in the Gal Oya National Park feeding

on herbaceous vegetation and shrub vegetation and

again the majority of the observations are of feeding on grass.

Elephants take in relatively small amounts of

food with each mouthful. These are gathered in

the trunk, inserted into the mouth, and chewed

prior to swallowing (page 45). On several occasions

it was possible to collect handfuls of food that an

elephant had dropped for one reason or another

prior to inserting it in the mouth and when these

were weighed it was found that the wet weight of

such mouthfuls of vegetation, whether grasses or

shrubs material, varied between 100 and 200 grams.

I also collected, by visual comparison, bunches of

grass and twigs which were estimated to be approximately the same size as those taken by elephants when feeding on different types of plants

and these also weighed approximately 100 to 200

grams each. Based on Benedict's (1936:159-167)

data on the food intake of Asiatic elephants and

on observations made in Ceylon on captive animals,

an adult elephant appears to have a daily food

intake of approximately 150 kilograms wet weight

per day. At an average weight of 150 grams per

mouthful, this would mean that the elephant would

have to take in approximately 1000 mouthfuls of

food during a day's feeding. If the elephant were

feeding steadily at the rate of one mouthful per

minute, this would take approximately 17 hours or

at two mouthfuls per minute 8.5 hours. Elephants

vary the rate of feeding, but time spent in actual

feeding would, by extrapolation from these data,

be approximately 12 to 14 hours per day. As there

are other locomotor components involved in the

feeding, this time can then be expanded appropriately and it would appear that the calculations

based on required food intake do not differ greatly

from those of observations of time spent feeding

(p. 58).

Using the average daily intake of 150 kilograms

(wet weight) per day and allowing for the water

content of the food (most plants measured averaged

40% dry matter, 60% water), the intake is approximately 60 kilograms of digestible material.

Using an average value for caloric density of 4

Kgcal/gm (see Table 19), this amounts to a daily

caloric input of 240,000 Kgcal/day. With a digestive efficiency of 40 percent, according to Benedict

(1936), this produces an estimate of digestible

energy of 96,000 Kgcal/day. Benedict (1935:265)

measured the resting metabolic rate of one large

adult female Elephas and found an average of

65,000 Kgcal/day. Comparing these estimates it

can be seen that if the data extrapolated from field

observations is correct the elephant, in the wild, is

existing on a daily caloric input only 50 percent

greater than the resting metabolic rate.

From similar calculations, based on studies in

Africa, Petrides and Swank (1965) have concluded

that the elephant is a relatively inefficient herbivore

in that it produces much less growth for the

amount of plant biomass consumed than do voles,

deer, or cattle, despite its larger standing crop. If,

however, the elephants maintenance requirement is

only 50 percent higher than resting requirement as

opposed to 100 percent for ruminants (Crampton

and Lloyd, 1959), it would appear that the elephant

is more efficient with respect to maintenance. The

significant point here, I feel, is that the stratagem

of the elephant is to put energy into maintenance

of a high standing crop (at the expense of rapid

growth) while that of the ruminant is to put energy

into growth and reproduction. Both are efficient

for the maintenance of a population. In fact one

could state that the elephant is more efficient in

that it has a lower ratio of forage consumed to

animal biomass than do the ruminants (Petrides

and Swank, 1965) but I do not think it legitimate

to compare the efficiency of maintenance of a

standing crop to the efficiency of growth.

When feeding on shrub or tree vegetation particularly, the total amount of plant matter which

is removed from tli-e tree is not ingested. In fact

a relatively large proportion is dropped to the
SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

ground. When feeding on some types of plants,

this amount may be quite low but when feeding

on others, a relatively large proportion of plant

biomass may be discarded and not eaten. This

occurs especially when the animals are feeding on

bark, when they tear off an entire branch and

consume only the bark of that branch. If then we

consider the foraging efficiency of the animal to be

the ratio of plant biomass eaten to the plant

biomass removed but not ingested, this would appear to be on the average about 50 percent when

feeding on the leafy matter of shrubs and trees. It

will be higher, probably in the order of 80 percent,

when feeding on grasses and much lower, in the

order of 20 to 25 percent, when feeding on the

bark of such plants as the wood apple (Feronia

limonia).

The other factor which must be considered in

connection with feeding behavior is the number or

proportion of trees from which the elephant feeds.

Detailed counts were not made of all trees fed

upon in any of the plots sampled (page 18) but

estimates were made using the scale: <5%, 5-10%,

10-25%, 25-50%, >50%. In all savanna plots

sampled the amount of feeding on trees was

estimated to be in the lowest category. In forest

plots the relative amounts of feeding were estimated

to fall within the second and third categories. Thus

it would appear on the average that the elephants,

although they eat a large percentage of the species

present in an area, feed from only a small percentage of the individuals.

The feeding habits of the elephants in the Gal

Oya study area show a remarkable similarity to

those reported for Loxodonta by Wing and Buss

(1970) both in the manner of feeding and in the

types and amounts of food taken. That this differs

from the observations of Buss (1961) and Buechner

and Dawkins (1961) who found a great deal of

destructive feeding and a diet consisting almost

entirely of grass is attributed by Wing and Buss

(1970) to greater elephant densities and habitat

destruction by man-made fire in the areas studied

in these earlier works.

It would appear then that under optimal conditions, both species show a variability in their

diet, taking both herbaceous and woody material.

Also they crop only a relatively small percentage of

the plants in any area. That deviations from this

norm can be ascribed to the influence of man now

seems apparent. These latter factors are of great

importance in any consideration of conservation of

the elephant (pp. 101-105).

DENSITY AND BIOMASS

Considering now an area of 720 square miles which

constituted the major study area, the overall density

of elephants in this area is 0.43 animals per square

mile (0.17/km2). If we consider only the undeveloped land, that is, leaving out agricultural land,

village sites, and tanks, this amounts to a total area

of 515 square miles. The density then is approximately 0.60 elephants per square mile (0.23/km2

).

Since some portions of the agricultural land are

used by the animals especially at the onset of the

rainy season, a more correct estimate of crude

density would probably lie somewhere between

these values, estimated to be in the region of 0.49

to 0.50 animals per square mile (0.19/km2).

Based on weights recorded for tame elephants

by Kurt and Nettasinghe (1968) and allowing for

the frequencies of different size classes, it is estimated that the average weight per elephant is

about 4000 pounds (1800 kg). Using this estimate

as a base, the total elephant biomass for the area

is 600 tons and the average biomass density is 1.2

tons per square mile. As was demonstrated in

Figure 22, however, the distribution of elephants

within this area are not uniform and the crude

density, which has been estimated above, does not

necessarily apply to any particular area; these

densities and biomass estimates will differ for each

of the areas concerned. Density and biomass of

elephants are highest in the regions around the

Amparai airport and in the Hatpata area. Even

breaking down the density and biomass on this

basis does not give a true picture for any one time

but simply the overall average for an annual period.

As was discussed previously (pages 75-78) elephants

spend relatively long periods of time in very small

areas, so for any given day or week the effective

density in any given area may be as high as 30

animals per square mile giving a biomass density

of 50 tons per square mile.

The observed overall density of elephants in the

Gal Oya region is similar to that reported by

Eisenberg and Lockhart (1972) for Wilpattu

(0.12/km2) and probably represents the average
NUMBER 125 97

for Ceylon. Comparable estimates for other parts

of Asia are not available but one can extrapolate

from the data of Hislop (1961) and Stevens (1968)

that the density in Taman Negara, Malaysia, an

area of 1677 square miles (4300 km2) with an

estimated elephant population of 23 must be very

low indeed.

Comparisons of estimates of densities reported

for Elephas and Loxodonta are shown in Table 21.

TABLE 21 .—Comparison of biomass density estimates

for Elephas and Loxodonta

Region

Elephas

Gal Oya, Ceylon

Wilpattu, Ceylon

Uttar Pradesh, India

Loxodonta

Albert National Park,

Congo

Bunyoro, Uganda

Tsavo, Kenya

Murchison North, Uganda

Muichison South, Uganda

Mkomasi, Tanzania

Density / km2

0.19

0.12

0.39

0.2-3.36

3.43±1.00

ca. 1.1

1.5

2.2-4.0

<1.0

Authority

McKay (herein)

Eisenberg and

Lockhart (1972)

Singh 1969)

Bourliere and

Verschuren (1960)

Laws, et al. (1970)

Laws (1969a)

Laws (1969a)

Laws (1969a)

Laws (1969a)

With the exception of the lowest estimate by

Bourliere and Verschuren (1960) (which was only

for one small part of Albert Park), all of the estimates for East Africa show densities 5 to 20 times

greater than those existing in Ceylon. All of these

areas censused have been in some way affected by

man. Bourliere and Verschuren (1960) attribute

the large elephant population of Albert National

Park to immigration from surrounding areas. This

view is supported by Hubert (1947) who reports an

increase in the elephant population of a 1200

square kilometer sector of the park from 150 in

1931 to 500 in 1940. Similar increases are reported

for other areas (Laws, 1970). These increases, and

the problems they have caused, are at least in part

a result of man's intervention (see page 42).

While the elephant is certainly the most important terrestrial herbivore in the Gal Oya National Park, it is not the only one. There are large

populations of water buffalo (Bubalus bubalis),

particularly in the eastern portion of the park and

of wild boar (Sus scrofa) particularly on the eastern

fringe of the park (Figure 60). Two species of deer

also occur, the sambar (Cervus unicolor) and the

axis (Axis axis), which are relatively thinly distributed throughout the entire region. Table 22

shows the estimates of the densities and biomasses

of all the herbivores in the Gal Oya National

Park and its immediate surroundings, a total area

of 450 square kilometers, as determined during the

wet season of 1968. During this period, it was

estimated that an average of 100 elephants were

using this area at any one time. The data for the

other species are estimated of the total populations

for these species within the intensively studied

area. The elephant contributes almost one-half

of the total herbivore biomass of this area during

this period. The only other herbivore with a

biomass density in the same order of magnitude is

the water buffalo, the remaining herbivores contributing only about 20 percent of the total

biomass. One fact should be mentioned at this

TABLE 22.—Density and biomass of elephants and other herbivores in Gal Oya National Park and environs

(175 mi2)

Species

Elephas maximus

Bubalus bubalis

Cervus unicolor

Axis axis

Sus scrofa

Lepus nigricollis

Presbytis entellus ....

Macaca sinica

Total

Estimated

total

population

100

470-500

175-250

250-300

200-250

2,650-3,500

1,500-2,000

200-250

5,545-7,850

Mean weight

(Ib)

4,000

600

300

100

60

5

10

8

Numerical

density

(animals/mi*)

0.6

2.6-2.9

1.0-1.4

1.4-1.7

1.2-1.4

15.0-20.0

9.0-12.0

1.2- 1.4

32.4-41.4

Total biomass

(Ib)

400,000

280,000-300,000

52300- 75,000

25,000- 30,000

12,000- 15,000

13,250- 17,500

15,000- 20,000

1,600- 2,000

799,350-859,500

Biomass

lb/mis

2,280

1,600-1,820

300- 430

145- 170

72- 84

75- 100

90- 120

10- 11

4,752-5,015

density

kg/km>

405.0

282.0-320.0

52.8- 75.7

25.5- 29.9

12.0- 14.8

13.2- 17.6

15.8- 21.1

1.8- 1.9

808.1-886.0
98 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 60.—Distribution of buffalo herds and wild boar in the

Gal Oya National Park. A —50 buffalo; B—100 buffalo; 25-50

boar; C=10ntbuffalo; D —50-75 buffalo; E = 250-300 buffalo;

100-125 boar.

time—more than half of the buffalo in the eastern

sector of the National Park are tame animals that

are herded by villagers from Dewalahinda and

other surrounding villages and grazed in the national park.

These data give an indication of the relative

effects of the different herbivores on the vegetation.

The elephant is a generalized feeder, feeding on

ground vegetation and on woody vegetation up to

a height of approximately 10 feet. The buffalo is

primarily a grazer although it does take some

browse and the wild boar is partially a grazer but

feeds mostly on the roots and tubers which it digs

up out of the ground. The axis and sambar within

this area are almost totally browsers; they seldom

come out into the grassy areas to graze. The hare

(Lcpus nigricollis) is a grazer and the gray langur

(Presbytis entellus) is an arboreal herbivore which

would be considered a browser in that it feeds

quite extensively on the leaves of trees and shrubs

although it does occasionally come down to the

ground where, among other things, it feeds extensively on the flowers of Mimosa pudica. Considering the relative biomasses of these various

herbivores, the competition with the elephant for

browse is relatively slight, whereas the competition

from the buffalo for grass is quite heavy (page 90).

Table 23 shows a comparison of the biomass

densities in Gal Oya with those in Wilpattu as

reported by Eisenberg and Lockhart (1972). The

total biomas at Gal Oya is only slightly larger

than that at Wilpattu. The major difference between these two areas is not in the presence or

absence of certain species but in their relative

abundance. Buffalo are more numerous in Gal Oya

while all species of deer are more numerous in

Wilpattu.

TABLE 23.—Comparison of biomass densities (kg/

km-) in Gal Oya and Wilpattu National Parks

Species

Elephas maximus

Bubalus bubalis

Cervus unicolor

Axis axis

Muntiacus muntjak

Tragulus meminna

Sus scrofa

Lepus nigricollis

Hystrix indica

Presbytis entellus

Macaca sinica

Total

Gal Oya Wilpattu

405.0

282.0-320.0

52.8- 75.7

25.5- 29.9

12.0- 14.8

13.2- 17.6

• •

15.8- 21.1

1.8- 1.9

808.0-886.0

217.2

73.4

157.9

262.8

5.9

1.9

8.1

14.9

5.3

19.0

• *

766.4

•Data from Eisenberg and

••Not estimated.

Lockhart (1972) .

The reasons for this difference in the abundance

of deer would seem to be in the suitability of the

habitat. The low scrub vegetation in Wilpattu is

probably capable of supporting more of these

browsers than is the forest of the Gal Oya region

with its relatively sparse understory. Mr. C. S.

Wickremasinghe, Divisional Game Ranger, Inginiyagala, has stated (pers. comm.) that deer have

always been scarce in the Gal Oya region and there

is no evidence to show that any disturbance or

shooting during construction of the dam at

Inginiyagala caused a decline in numbers. More

detailed studies of the deer (primarily Axis) will

be needed to attempt to answer this question.

The only comparable data from mainland Asia

are those of Schaller (1967) from India. He found

biomass densities of wild ungulates in Kanha National Park to be in the order of 600-700 kg/km2

.

With domestic stock added the total biomass

density for this area is 2400-2500 kg/km2. Without
NUMBER 125 99

the domestic stock, his data are comparable to ours

from Ceylon.

Spillett (1966) estimated the numbers of

ungulates in the Kaziranga Sanctuary, Assam.

Using his data it can be estimated that the biomass

density of herbivores in that region is about 3800

kg/km-. As his figures for elephant seem unusually

high, probably representing a seasonal concentration, a more reasonable estimate would be in the

order of 2000-2500 kg/km2.

The literature on biomass densities of ungulates

in Africa is quite large and includes several reviews

(e.g., Bourliere, 1963a, b; DeVos, 1969), but as

emphasized by Talbot (1964) the variety of means

by which various authors arrived at their estimates

makes any meaningful comparison difficult. An

adequate treatment of this subject would require

more space than can reasonably be included in this

discussion. As such it is necessary to only emphasize that a wide variety of biomass densities have

been reported (see Bourliere, 1963a), the variety of

which is influenced by many factors including the

influence of man and his domestic animals (DeVos,

1969). Some communities appear to be able to

support a larger standing crop of ungulates than

others but, as DeVos (1969) adequately emphasizes,

more detailed research is necessary before we can

understand the factors causing such differences.

If the situation in Africa is unclear, the situation

in Asia is moreso. We do not at the moment have

sufficient data to make meaningful comparisons

between habitats within that continent. Without

such data, and without a more detailed study of

the primary and secondary productivity of areas

such as Gal Oya, it is not possible to assess what

the carrying capacity of an area like Gal Oya

should be.

EFFECTS ON THE HABITAT

The elephant produces several effects on the habitat

which, besides affecting the plant communities

themselves, can affect other animals living in the

same area.

Water Holes and Trails

Elephants frequently dig holes in sandy stream-beds

during the dry season (see page 47). Mongooses

were observed in the vicinity of such water holes

and it seems likely that they will also be used by

deer, monkeys, and other mammals.

Trails which are used and maintained primarily

by elephants are regularly used by other terrestrial

mammals. A list of species encountered by us along

such trails includes: buffalo, sambar, boar, leopard,

and mongooses. Man, of course, also makes use of

thes trails.

Effects Associated with Feeding

In general an elephant when feeding on a tree or

shrub does not tear down the entire plant; rather

it tends to remove small twigs, and for certain

species, entire branches. In the plots surveyed

around the Gal Oya area (see page 18), the relative

proportions of trees and shrubs fed upon by elephants were found to vary between 10 and 25 percent of the total trees in the area (see page 96).

This would appear to be somewhat lower than

those data obtained by Eisenberg and Lockhart

(1972) for Wilpattu and Mueller-Dombois (n.d.)

for Ruhunu National Park. As discussed by

Mueller-Dombois (n.d.), the patterns of feeding by

the elephant can in some instances alter the shape

and form of the tree. This is particularly true of

low growing trees and shrubs where the elephant

has access to the crown rather than simply to the

lower branches. Species which are particularly

affected in this way are Feronia limonia and

Dichrostachys cinerea. As was mentioned, a few

species of trees may be broken down completely.

One species in the Gal Oya area that is particularly broken down in this manner is Bauhinia

raccmosa. Several instances were found where the

elephants had broken this tree down but the tree

remained growing in an almost horizontal position

(Figure 61). This species of plant seemed particularly resistant to total destruction by the elephant

whereas some other species which were broken

completely, such as Terminalia chebula and

Atiogeissus latifolia, died after being broken.

The amounts of food which an elephant consumes must have an effect on the plant community.

Based on the estimate made earlier of a daily food

intake for a mature (4000 kg) elephant of 150

kg/day the annual consumption of food will be

55,000 kilograms. Correcting this value for the

average size of elephants in this population gives

a value of 27,500 kg/animal/yr. At the observed
100 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

FIGURE 61.—Bauhinia racemosa shrubs broken down by elephant, Amparai, August 1969.

density, and with an average feeding efficiency of

50 percent, the plant biomass "used" by elephants

will be approximately 27,500 kg/mi2 (approximately 10,500 kg/km2

).

As mentioned earlier, not all the plant material

pulled from a tree is eaten by the elephant. Buss

(1961), Buechner and Dawkins (1961), and others

have described how various ungulates may browse

upon branches removed from trees and left on the

ground, thus gaining access to material which

otherwise would not be available to them. No

instances of this were observed during my study,

but the possibility cannot be denied. Besides providing these potential symbiotic relationships, the

removal of branches by elephants could make them

potential competitors with primates. Struhsaker

(1967) in his study of the vervet monkey in East

Africa found that the greatest competitor for food

was the elephant. Regardless of their usefulness to

other mannals these broken branches are readily

used by termites.

The effects of feeding do not end with ingestion.

As stated previously (page 50), an adult elephant

defecates approximately 18 to 20 times a day,

producing some 180-200 kilograms of feces. These

feces are fed upon by a variety of insects. In

Ruhunu National Park especially, and in most of

the drier areas of Ceylon, dung beetles (Carabidae)

are extremely common and at least three species

of these carabids were observed to feed upon the

dung of the elephants. Another insect which was

found to feed on elephant dung was termites. The

termites frequently invade a bolus of feces and on

two occasions were observed over a period of days

to begin construction of a nest beneath a pile of

feces. On both of these instances, the feces were in

a roadway of dry compacted earth. One of them

unfortunately was destroyed at a relatively early

stage by vehicular traffic but another one on an

infrequently traveled road grew to the size of a

typical termite mound. Although there are very

few data to support this, it would appear that the

elephant dung deposited on trails is very frequently

used by termites in establishing new colonies. Sev-
NUMBER 125 101

eral instances were observed where termite mounds

occurred in the pathway used by elephants. After

the termite mound has grown, the elephant pathway is diverted around the side.

A further effect that the elephant can have on

the environment is in the distribution of plants by

ingesting the seeds when feeding on branches.

Observations from feces collected in Ruhunu

National Park and in the Gal Oya area during 1967

and 1968 showed that seeds were present in anywhere from 40 to 80 percent of the samples of feces.

In most of these instances, the seeds were entire,

the seed coat not having been broken and it seems

quite possible, as discussed by Hladik and Hladik

(1967), that these seeds would remain viable although no tests of the viability were made. In this

way the elephant can act as a potential distributing

agent for many of the species which it feeds upon.

The final effect of elephant on habitat is cropraiding, which is as much the effect of man as of

the elephant. (For further discussion of this aspect

see pages 102-103).

Elephant and Man

THE CURRENT PROBLEMS

Agriculture and Movements

As was mentioned in the description of the study

area, the Gal Oya valley has been subjected to rapid

agricultural development over the past 25 years.

Figure 17 shows the distribution of agricultural

land in the vicinity of the Gal Oya study area as

of 1969 and projected areas of expansion for the

1970s. As can be seen from this map, the greatest

amount of agricultural development has been concentrated along the coastal strip and in the vicinity

of Amparai, with a second major block of paddy

land between Amparai, Namal Oya, and Inginiyagala. Smaller blocks already developed exist in the

region along the irrigation canal coming from

Jayanthi Wewa and in the vicinity of Ekgal Aru.

Development plans call for a further extension of

agricultural development in the areas north of

Amparai and south and east of the present limits of

agriculture between Inginiyagala, Ekgal Aru, and

Ambalam Oya. The development areas around Ambalam Oya were already under construction in

1969. At the moment concrete plans for development are in existence only for the drainage of the

Gal Oya valley, although plans without any definite

timetable also exist for development of the Heda

Oya which drains past Lahugala Tank towards

Pottuvil on the east coast. Smaller isolated patches

of agriculture exist around Buddama, Baduluwela,

Bulupitiya, Mullegama, Siyambalanduwa, and a

few other small villages. The Gal Oya region is

bounded on the west by agricultural land in the

vicinity of Bibile and Moneragala. The land around

Bibile itself is developed primarily for paddy although as one moves west from Bibile into the hills,

tea becomes predominant, while around Moneragala the primary crop is rubber.

The herd that inhabits the areas surrounding

the Amparai airport, north of the town of Amparai,

is at present almost completely surrounded by

agricultural land. The Hatpata herd, which inhabits

the southeastern sector of the Gal Oya National

Park, while not completely surrounded by agriculture, is affected by the presence of paddy cultivation along the Pallang Oya and around the

Jayanthi Wewa reservoir. Considering this latter

herd first, it was observed during the period of this

study that the various groups that constituted this

herd did tend to move directly eastward from the

National Park area itself into that section of land

which has been slated for development lying between Inginiyagala and Ekgal Aru. At the time of

this study, the elephants were known to raid the

paddy fields of the Pallang Oya development area

and the cultivated areas of an agricultural settlement area which was established at Ekgal Aru. It

seems highly probable that with increased expansion of agricultural land in this particular area

the amount of crop raiding by this herd will increase and the numbers of elephants in this herd

will probably be reduced by shooting on the part

of the cultivators.

Considering now the Amparai airport herd, Figure 62 shows the eastern portion of the home range

of this herd with the areas of agricultural land and

natural vegetation demarcated. The dashed arrows

on this map indicate the commonest routes of

movement between sectors of the home range used

by the elephants during 1968 and 1969. These, as

can be seen, pass through two narrow necks of

natural vegetation between areas of agriculture and

one actually passes through a narrow belt of agri-
102 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

A Agriculture

F Forest

A Crop damage

FIGURE 62.—Movements of the Amparai airport herd in relation to agricultural land. Triangles indicate sites at which

crop damage occurred during 1968-1969.

culture along the irrigation canal. In this latter

area, the land on the eastern side of the channel

was only opened for agriculture during 1967 and

1968 and by the end of 1969 the elephants were

still using this newly opened land as a regular

pathway. The presence of men in this area did

not appear to deter the elephants at all from

moving through.

According to observations made by Mr. Bevis

Ekanayake, the Game Ranger from Inginiyagala,

and Mr. Joe Pereis, the Public Relations Officer

for the River Valleys Development Board at Amparai, the members of this herd were at one time

accustomed to move towards the south along the

narrow belt of forest between Kondavatavan Kulam

and Amparai Kulam, the two tanks which are

situated to the west of Amparai town. In the early

part of the 1960s the land to the south of these

two tanks was developed in part for paddy and in

part as a sugarcane plantation and for several years

after the initiation of these projects, the elephants

would move southward through this neck of forest

in order to feed in the paddy and sugarcane.

Several attempts were made during the 1960s to

discourage the elephants from coming down in this

direction including an attempt to drive the elephants toward the west, and the erection of an

electric fence running along a line between the

two tanks about a half mile north of the main

road. According to Mr. Ekanayake, the drive was

without result, but after several years of operation,

the electric fence has proved to be a sufficient

barrier and the elephants are no longer a problem

in the fields to the south of this region. During the

period of this study, no movement of elephants into

this area was observed. A second stretch of electric

fence was constructed between the western edge of

Kondavatavan Kulam and the limits of the village

of Paragahakelle, approximately two miles to the

west, in a further attempt to limit the southward

movements of this herd. As far as limiting the movements of the herd, this particular fence would seem

to have been effective, but between 1967 to 1969

sectors of the fence were broken down on three

occasions by solitary males who inhabit the area

around Kondavatavan and Himidurawa Tanks.

Further experiments with electric fences have

been made by the River Valleys Development Board

including the erection of a fence around the sugarcane in the vicinity of Ambalam Oya and along the

Namal Oya to the north of the town of Inginiyagala. These two fences have met with varying

success in that herds were frequently known to

break them down in order to pass through during

1967 and 1969.

Crop Raiding

Except for those few observations outlined above,

the majority of times that elephants were known

to come out into agricultural land were for purposes

of feeding rather than for movement through the

agricultural land. As one example from the Amparai airport herd, the black triangles in Figure 62

show the locations of crop damage by these elephants during 1968 and 1969. The areas where

crop damage occurred were distributed on both the

north and south sides of the range of this herd

although the most severe damage was incurred in

the three westernmost areas on the north side

around the Amparai airport itself. The westernmost

of these was in the region of the Youth Scheme

agricultural area at Mahakandiya on the western

side of the Left Bank irrigation channel. The

second was a small development area immediately

to the south of the airstrip; this particular village

was abandoned by the villagers in 1968 as a direct

result of the continued depredation on their crops

by the elephants. The villagers then moved to the
NUMBER 12 103

area to the south of Mahakandiya directly along

the Lett Bank channel which is right in the center

of the main migratory path of this herd. The

results of this unfortunately short-sighted move will

undoubtedly be evident even by the time of this

writing.

Unfortunately no data exist on the financial loss

caused by these crop raids and no such records are

kept by the River Valley Development Board, but

my own observations during 1968 indicated that

approximately 350 to 400 acres of paddy land were

either disturbed or rendered unproductive by the

elephants constituting this single herd.

Crop raiding by elephants in the Gal Oya area

is not restricted to this one particular location. It

occurs also in the areas around Paragahakelle,

Namal Oya, Ekgal Aru, and the Pallang Oya development. In all of these locations, the animals

known to come out and feed on the crops consisted

of both solitary males and herds. Such raids by

elephants on paddy land invariably occur at night

and a variety of devices used by the villagers to

attempt to frighten the herds including fires, noisemakers of various kinds, shouting, and the discharge

of firearms, often prove to be ineffective especially

towards solitary adult males. One particular adult

male terrorized the villagers in the region of Pallang

Oya during March and April of 1969. Whenever

the cultivators from this village attempted to

frighten the animal off by shouting or flashing

lights, he would respond by attacking and over

a three week period damaged approximately 25

buildings on the outskirts of the village.

In many parts of this region, the defenses taken

by cultivators towards the depredations by elephants are not restricted to fires or noise-making

devices. In fact, as is indicated by the large number

of elephants throughout the area who carry visible

cysts and wounds on the body and the observation

that 8 out of 14 elephants known to have died in

the area died as the result of gunshot injuries, it

is obvious that shooting of elephants is widespread

throughout the region. It would appear that, until

more adequate nonlethal devices are in general

use for deterring elephants from invading paddy

land, the high mortality from gunshot injuries will

continue for some time.

At the time of this study there were no herds

in the Gal Oya area which did not come into contact with agricultural land and cause at least some

crop damage.

Competition from Domestic Stock

There are some 200 domestic buffalo being grazed

within the Gay Oya National Park (see pages

97-98). These animals quickly reduce the grass on

the banks of the Senanayake Samudra to the point

where elephants must scarify the ground in order

to feed on the short grass.

In the Amparai sanctuary there are large numbers

of domestic stock which compete in a similar manner for the grasses there. If the trends observed

during 1967—1969 continue in this area, the combination of heavy grazing and frequent fires will

probably lead to a degradation of this savanna type

by reduction in the abundance of shrubs and

replacement of native grasses by the less palatable

Imperata cylindrica.

THE OUTLOOK

The problem faced at the moment has two aspects:

How to maintain a population of elephants, and

how to maintain an ecosystem?—neither of which

can be considered alone. As the human population

of Ceylon is increasing, more food, and thus more

agricultural land, is required annually. As the

production of food for human consumption and the

maintenance of natural ecosystems are competitive

there is an urgent need for the assignment of

priorities. Decisions must be made concerning the

amount of land that can reasonably be preserved

in a natural state. As emphasized over a decade ago

by Norris (1959), these decisions must be based on

a knowledge of the various factors affecting the

ecosystems under consideration.

Rapid, unplanned agricultural expansion can

result in the destruction not only of the land "developed" but of land intended to remain under

natural conditions. That such has happened in East

Africa has been well documented by Glover (1963),

Laws 1969b, 1970), and Laws, et al. (1970). A

combination of factors, including the forced movement of elephants into reserves as a result of agricultural expansion along with man-made fires and

suppression of poaching, have resulted in large

increases in the elephant populations of many East

African reserves. In many of these (especially Tsavo
104 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY

and Murchison Falls) the increasing pressure from

the elephants has resulted in drastic degradation of

the plant community, reducing savanna and even

forest to grassland. There is evidence to show that

the elephants may be capable of responding to

such changes by regulating their population increases (Laws, 1969a, b) and even evidence that

there may be a long-term cycle of which the present

trend is only a part (Boughey, 1963; Laws, 1969a);

but as reserves get smaller the probability of such

habitat degradation leading to the extinction of

entire faunas increases.

The question then is how can Ceylon benefit

from the experiences of Africa? With regard to

the elephant, the first approach to this question

is to determine what size of population is to be

maintained. Once this has been determined the

next step is to delimit an area known to contain

one or more herds approximating that number

and containing their entire annual ranges and

securing such an area as a park or other reserve.

It would be extremely naive to assume that this is

all that must be done. These are only the first steps

in a continuing process, but as the present urgent

need is rapidly becoming a crisis these are measures

which must be taken immediately. The often-heard

plea of "let us not do anything until we know

everything" (see Harthoorn, 1966) has no place

when an approximate solution can at least allow

time to investigate the finer details (Laws, 1969b).

The following recommendations are, admittedly,

approximate, being based on a preliminary study.

The data reported in this study represent little

more than two years observation of elephant

ecology in the Gal Oya region. That continued

research is needed, particularly on the seasonal

movement patterns, food utilization, and effects on

the plant community, cannot be overemphasized.

Nevertheless, it is my opinion that, if certain

measures are taken as soon as possible and if

research is continued to augment and revise these

plans, then a population of elephants and a unique

ecosystem can be maintained in the Gal Oya valley.

RECOMMENDATIONS

1. No herd of elephants spends the entire year

within the present boundaries of the Gal Oya

National Park (Figure 22) . The boundaries of the

park must be extended or some measure taken to

halt the expansion of agriculture into the dry season

ranges of the herds that are to be maintained.

If all four herds which currently use the park are

to be maintained, then the park boundaries must

be extended to the north, west, south, and southeast. As the land to the north is generally unsuitable

for agriculture, such an extension might be limited

to the west, south, and southeast with little danger

to the northern herd.

2. A buffer zone should be established between

the park and areas of extensive agriculture. Within

this buffer zone the only form of agriculture which

should be allowed is the chena. Restricted chena

rights within this zone could be given to those

villagers already resident in the areas around Baduluwela, Buddama and Bulupitiya. The buffer

zone should be outside the normal home ranges of

the herds or at least on their fringes. Some cropraiding within this zone will be inevitable but the

presence of the buffer itself should cut down or

eliminate raids on paddy fields outside the zone.

3. If crop raiding should continue beyond the

buffer zone into areas already settled and in areas

where such a zone is impractical (Pallang Oya,

Namal Oya), further experimentation should be

made with the use of electric fences which have

proven effective as long as they are regularly

patrolled and maintained.

4. All grazing of domestic stock within the park

(and the buffer zone) must be stopped. Grazing

by domestic buffalo was the only adverse effect

recorded in the park and other than this measure

no other form of control over potential competitors

is immediately necessary.

5. No attempt should be made at the present

time to suppress fires in the Talawa savanna. Research should be undertaken on the optimum

frequency of burning so that in the future, productivity can be maintained at an optimal level.

But until such information is available, the present

conditions should be allowed to prevail.

Burning of areas other than the Talawa should

be suppressed. The fishermen who use the Senanayake Samudra should not be permitted to remain

ashore and light fires in the short-grass zone.

6. Unless all further agricultural expansion

within the Amparai sanctuary is halted the herd

inhabiting the area around the airport is doomed.

Two alternatives are open.
NUMBER 123 105

a. Halt all further agriculture within this area

and relocate the villagers who have already settled

along the Left Bank channel. In this way the herd

will be able to maintain its normal movement

patterns. In addition, the presently large herds of

domestic cattle grazed in the area must be reduced.

These steps will not eliminate the crop damage

caused by these animals but they will ensure survival of the present level of interaction.

b. If expansion of agriculture in this area cannot

be halted and eventually reversed to provide even

a narrow buffer zone, then the elephants should

be removed. This population is so small and has

no other refuge so further interaction will inevitably be detrimental to both the elephants and man.

A kraal should be held under supervision of the

Department of Wild Life Conservation and the

animals, once tamed, sold at auction. No attempt

should be made to drive these animals into the

National Park.

7. Further research is needed, but the suggestion

made by Norris (1959) for an "elephant corridor"

between Ruhunu National Park and Lahugala

Sanctuary should be examined seriously as this may

well afford protection to a further population of

about 150 elephants. If this is to be done, the

Lahugala Sanctuary itself should be expanded and

elevated to the status of National Park.

At the time of this study the populations of

elephants and other mammals in the Gal Oya

National Park and surrounding areas were in a

relative state of equilibrium. A certain amount of

poaching on sambar and buffalo existed but the

Department of Wild Life staff were already in the

process of attacking the problem. If at least the

first five recommendations listed above are considered and followed, this equilibrium can be maintained. The Gal Oya National Park offers more

than a unique ecosystem, worthy of conservation

for that reason alone. The lake, surrounded by

abrupt, rugged hills, the ever-changing distant view

of the central mountain range, the sunsets which

each day are never the same, the immense flocks

of water-birds, all combine to make any visit,

however short, to this area a unique esthetic

experience. Perhaps it is this view, rather than the

coldly ecological one of the need to provide a

habitat for one spectacular species which will ultimately prove the more important argument for

the preservation of this area. If the elephant should

be a symbol for both views, its continued existence

here will be essential and must be assured.

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Appendixes

Maha

Oy

81° 81° 30' 81° 55'

FIGURE 63.—Map of southeastern Ceylon showing some place names used in text.
Appendix 1: Gazetteer of Place Names Used in Text

Name

Akkaraipattu

Alutnuwara

Ainbalam Oya

Amparai

Amunuhela

Andella Oya

Baduluwcla

Batticaloa

Bibilc

Buddama

Bulupitiya

Bulupitiyahcla

Damana

Daniagla

Dewalahinda

Divulana

Ekgal Am

Embilipitiya

Gal Oya

Gal Oya National Park

Gonagala

Hambantota

Hambegamuwa

Hatpata

Heda Oya

Heen Wewa

Himidurawa

Iginiyagala

Jayanthi Wewa

Kalmunai

Karanda Oya

Katagamuwa

Kataragama

Kirindi Oya

Kitulana

Kondavatavan Kulam

Latitude

o t

07

07

07

07

07

07

07

07

07

07

07

07

07

07

07

07

07

06

07

07

06

06

06

07

06

06

07

07

07

07

06

06

06

06

06

07

13

19

10

17

17

28

05

43

10

12

15

15

12

15

10

28

15

20

18

11

20

07

32

10

50

21

17

13

08

25

55

24

25

12

53

17

Longitude

0 t

81

80

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

80

81

81

81

81

80

81

81

81

81

81

81

81

81

81

81

81

81

81

51

59

46

40

19

43

13

42

13

29

20

19

39

23

34

35

42

51

46

29

27

07

57

32

46

26

36

32

33

49

45

24

20

18

23

38

Name

Kossapola

Kotabowa

Kumana

Kumbukkan Oya

Lahugala

Maduru Oya

Mahakandiya

Maha Oya

Mahaweli Ganga

Medagama

Menik Ganga

Moneragala

Mullegama

Namal Oya

Navakiri Aru

Nilgala

Palatupana

Pallang Oya

Panama

Pannela Oya

Paragahakelle

Passara

Pottuvil

Rote Kulam

Ruhunu National Park

Senanayake Samudra

Sengamuwa

Siyambalanduwa

Tanamalwila

Tangalle

Timitar

Tirrukkovil

Wadinagala

Wellawaya

Westminster Abbey

Wila Oya

Yala

Latitude

07

07

06

06

06

07

07

07

08

07

06

06

07

07

07

07

06

07

06

07

07

06

06

06

06

07

06

06

06

06

07

07

07

06

07

06

06

09

06

31

30

54

52

21

32

27

02

22

52

20

16

28

11

17

07

45

08

15

56

52

55

21

11

54

54

26

01

01

07

07

44

02

46

22

Longitude

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

81

80

81

81

81

81

81

81

81

30

17

42

42

42

31

34

21

13

16

31

20

27

31

43

22

24

32

48

47

36

09

50

48

27

29

46

33

08

48

52

51

32

06

32

48

31

111
Appendix 2: Data on Flapping of Ears

Heather

RAIN

OVERCAST

Wind=0

OVERCAST

Wind= l

Animal

Ad-D

Ad-L,,

X

Ad-ht

Ad-ht

Ad

Ad

Ad-L,.

Ad-Lj

Ad-L,

X

SA

SA

S A T

SA

X

Ad ht

Ad

Ad

Ad

Ad-D

Ad-L,

X

SA-t

Date

121267

191267

210767

210767

210767

210767

191267

191267

191267

210767

210767

210767

210767

190767

190767

210767

210767

121267

121267

190767

Time

1430

1100

1510

1600

1510

1600

1300

1300

1300

1510

1600

1600

1130

1545

1545

0825

0830

1545

Fans/Bout

(xof5)

before/after

15/1.3

1.0/1.0

0.8

1.0

1.5/1.6

2.1/15

1.5/2.0

1.2/1.0

1.4/1.2

2.6/2.8

3.8/2.8

2.4/35

3.6/5.4

1.0/15

1.4/15

2.4

3.5/3.4

7.5/9.0

3.8/2.6

6.6/5.2

2.0/2.4

1.6/2.4

4.2/5.4

3.4/5.1

4 5

15

1.4

2.0

1.9

1.8/1.6

0.9/1.2

2.4/2.4

2.0/2.4

1.2/1.0

1.2/1.2

1.9/1.4

0.9/0.9

1.6

1.7

1.6

Interval

(sec.) Ears

(xof5) extended*

8.1

3.1

11.7

7.6

5.0

7.3

5.6

5.3

25

1.8

25

2.8

3.4

10.4

5.8

4.7

25

25

3.3

2.5

3.8

3.5

4.8

3.7

3.25

75

15.4

3.6

45

5.9

3.3

4.8

5.5

4.0

5.9

13.6 +

5.4 -f

6.6

8.8

85

1.65 8.5

112
NUMBER 125 113

Appendix 2:—Continued

Weather Animal Date Time

Fans/Bout

(x of 5)

before/after

Interval

(sec.)

(x of 5)

Ears

extended

OVERCAST

Wind=2-3 Ad-ht 190767

230767

1705

1600

Ad

SA-T

SAT

SA-t

230767

190767

230767

190767

1600

1705

1600

1705

1.1

1.0/1.0

1.2/1.0

_

1.1

1.2

1.7

1.0/1.0

2.2

11.9

2.9

4.0

_

6.3

5.3

4.0

9.2

6.4

—

_

_

Stands with

ears extended 10 min.

_

_

_

_

1.5 62

SUN

Wind=l Ad=:ht

Ad-ht

Ad

Ad-pt

190767

230767

230767

230767

1110

1100

1100

1100

SAT

SA

230767

230767

1600

1550

3.2

1.6

1.1/1.6

1.1/1.1

2.0/2.0

2.4/2.0

1.0/1.2

1.2/1.0

1.7

1.6/1.4

1.6/1.6

1.8/1.4

1.7

4.8

3.8

7.0

62

2.8

5.8

4.9

7.9

5.5

2.0

6.4

6.1

4.8

SUN

Wind=2-3 Ad

Ad-ht

X

S A T

SA-T

SA

230767

230767

190767

230767

230767

0755

0820

1035

2.2/1.0

2.0/1.9

3.0/3.0

2.8/25

2.5

2.2

2.2

2.2/2.0

3.6/2.6

3.0

4.2

19.7

8.6

112.0

25.5

41.4

3.1

3.3

19.9

18.3

8.6

3.0

2.9 9.5

* -f=yes; -=no.

U. S. GOVERNMENT PRINTING OFFICEi 1971 484-342/34



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