THE MALAYAN NATURE JOURNAL ~.

Vol. 19, No. I May 1965

MALA YSIAN CA VES ISSUE

THE

MALAYAN NATURE JOURNAL

Vol. 19 MAY 1965 No. 1

CONTENTS

Page

Malaysian Caves: Introduction by J . A. Bullock - 1

The Formation of Limestone Caves in Malaya by D. J. Gobbett 4

Caves of Sarawak and Sabah compiled from The Geology of Sarawak and Sabah caves by G. E. Wilford 13

The Limestone Caves and Cave Deposits of Perlis and Nof~h

Kedah by C. R. Jones 21

Further Cave Exploration and Archaeology in East Malaysia by Tom Harrisson 31

Early Mahayana Buddhist Shrines III the Malayan Limestone by Alastair Lam:b

The Prehistoric Archaeology of Malayan Caves and list of

36

archaeological sites by B. A. V. Peacock - 40

The Ecology of Malaysian Caves (and a note on the faunistic list from Batu Caves) by J. A. Bullock - 57

Microcosms of Batu Caves and a List of Species collected at Batu Caves by H. E. McClure - 65

Gua Anak Takun: Ecological Observations by F. L. Dunn 75

Identification of Malaysian Cave Bats by Lord Medway 88

The Conservation of Caves in Malaya by P. R. Wycher/ey - 108

1

MALA YSIAN CA VES

Introduction

by

J. A. BULLOCK

The concept of a symposium on Malaysian caves originated with my predecessor in office, Mrs. J. U. Poore, who intended to include several articles on caves within a single issue of the journal. The subject of caves proved to be so large that such a treatment appeared to be inadequate and instead it was decided to make over a whole issue to the subject. Despite this prodigality, even a whole issue is insufficient to cover all aspects of caves in so far as they are of interest to naturalists. Thus, the great and important discoveries at Niah Great Cave, where human and mammalian remains have been recovered from deposits spanning the last 100,000 years, receive but scant mention. These finds have recently been summarised by Harrisson (1964) and Lord Medway (1964) who deal respectively with human remains and artefacts, and with mammalian remains. Those interested in pursuing this topic should consult the two articles in 'Studies in Speleology' and the many articles in the Sarawak Museum Journal.

Little also has been said about methods of study. This is partly because of lack of space but also because, in the case of archaeology, the extraction and examination of specimens is a highly specialised task. So far as the biologist is concerned, normal collecting methods are quite adequate to give a fair haul , perhaps supplemented with a light-trap for flying insects and a few Berlese funnels for the extraction of small animals from the guano. A recent collector's guide (Hamilton­Smith, 1962) gives a useful survey of the subject. It should be emphasised that indiscriminate collecting is most undesirable and can easily lead to the extinction of a population in a cave. Populations of many cave animals are quite small and maintain a tenuous balance with their environment. In many cases this balance is very fine and the casual removal of even a few specimens may reduce the population to a level below that at which it can s).lrvive.

Insofar as the archaeologist is concerned, a cave is any hollow which could provide permanent shelter for a group of human beings, offering protection from the weather and from enemies. To the geologist and biologist, the cave has to penetrate the substrate rather further and, in the case of the biologist, include an area of virtually complete darkness, in which only the truly cavernicolous forms can

Malay. Nat. J. 19(1): 1- 3.

2 MALAYAN NATURE JOURNAL

exist. This proviso is necessary since the twilight peripheral zone, which forms a gradual transition from bright sunlight to cavernous gloom, harbours many animals and plants which can tolerate and even thrive in low light intensities while not being able to exist in 'true' cave conditions. These grade at one end into the fauna and flora of the 'outside world'; at the other into the cave fauna (and flora) proper.

The most important and impressive caves in the Malaysian region are those found in the numerous limestone outcrops. In virtually everyone of these outcrops, caves occur and to this extent a distribution map of Malaysian caves is a map of the limestone outcrops. It should not be forgotten however that other caves do exist. On Pulau Tioman, Lord Medway and I visited at least six caves, all of them small but none calcareous, which yielded both archaeological (Medway, 1962) and biological data (Bullock, in press; Medway, in press) including a new species of toad (Hendrickson. in press) . Thus, although all authors in this issue concentrate on limestone caves almost exclusively, there are other caves which will repay study.

There are three main groups of scientists interested in caves. First there is the geologist who is interested in the form, structure, causation, etc., of the cave and its matrix. On this subject we have three contributions, ranging from a discussion of how caves are formed in limestone through a summary of the cave-bearing areas of Sabah and Sarawak to a more detailed study of a single cave-bearing area in Kedah and Perlis.

The second group interested in caves are the archaeologists whose interest stems from the considerable use made of caves by early man, first as a shelter and later as a 'holy' place for worship and/or burial. (This religious role is still retained to this day as witness the Hindu temple at Batu Caves and the temples around lpoh.) Here again we have a mixture of views including a discussion of the criteria, methods and difficulties involved in selecting caves of archaeological interest, an outline of the history of cave archaeology in Western Malaysia, and an account of very recent finds of Buddhist votive tablets in two caves in Perlis.

In the field of biology, interest stems partly from the many peculiar animals which live in caves and partly from the comparatively simple ecology of the cave as compared with the complexity of the Malaysian primary forest. The orientation of the contributions is entirely zoologi­cal since little appears to be known of the bacteria and fungi which inhabit the caves. The contributions in this field include some general

VOL. 19, MAY 1965 3

considerations in cave ecology, two differently orientated accounts of single caves, and a taxonomic account of one of the most important groups of cavernicolous animals, the bats.

Finally, we have a single article on the conservation of caves. The chief threat to caves lies in the utilisation of the limestone for various commercial uses; the partial destruction of the Batu Caves massif and of various hills around Ipoh for this purpose is well-known to many Malaysians. It is only through the constant attention of conservationists, and the cooperation of various government depart­ments, that any effective protection can be given. Other causes of damage and disturbance in the caves are the activities of guano-diggers and collectors of edible birds' nests. The guano-digger poses a danger mainly to archaeological remains although his interference must also affect the fauna to some extent. The birds' nest collector is relatively innocuous, since it is in his own interest in the long run to maintain the bird colonies- otherwise he will be faced with diminishing returns. Provided care is taken that he appreciates th_e simple tenets of good cropping and husbandry, there is no reason why his activities, which are often of long-standing, should pose any problem.

We are indebted to all those who contributed to this issue and to the many others who have assisted in different ways. We are especially grateful to the Editor of the Journal of Tropical Geography for the loan of two blocks used in illustrating Dr. Gobbett's article, and to the Director, Geological Survey, Borneo Region, and the Government Printer, Brunei , for the loan of the blocks for the two maps in the summary of Dr. Wilford's paper.

Literature cited

BULLOCK, J .A. (in press). Papers on the fauna of Pulau Tioman. Introductory report on the arthropods. Bull. nat. MilS. , Singapore.

HAMILTON-SMITH, E. , 1962. Allstralian Cave Fauna- Notes on collecting. 19 pp. (duplicated) published by the author, 17, Helwig Ave. , Montmorency, Victoria, Australia. (price sh. 5/ -).

HARRISSON, T. , 1964. Borneo caves with special reference to Niah Great Cave. Studies;n. Speleology J (1) 26- 32 (with 33 refs.)

HENDRICKSON, J.R . (in press). Papers on the fauna of Pulau Tioman. The' Amphibia. BIIII . nat. Mi.IS., Singapore.

MEDWAY, LORD, 1962. Archaeological notes from Pulau Tioman. Fed. MilS.

Jour . 7, 55- 63.

---1964. Post-Pleistocene changes in the mammalian fauna of Borneo. Archaeological evidence from the Niah caves. Studies in Speleology J (1) 33-5.

--- (in press). Papers on the fa una of Pul au Tioman. The Mammals. Bul/ . /1at . Mus ., Singapore.

4 MALAYAN NATURE JOURNAL

THE FORMA TlON OF LIMESTONE CA VES IN MALAYA

by

D. J. G OBBETT*

The Nature of the Limestone Areas

Limestone formations outcrop in many scattered localities in the northern half of Malaya (fig. 1). Although they vary considerably in geological age, most of these formations are composed of dense, recrystallized , massive limestones containing little impurity. They are eroded to form a karst topography of a particular type, forming characteristic hills with sheer rock walls and jagged summits rising like teeth from the surrounding landscape. The hills are often grouped into small massifs, for example in the Kinta Valley, but they also occur as isolated crags. Typically they are surrounded by a plain covered with alluvium but underlain by limestone. In the Langkawi Islands and northwest Perlis more extensive limestone massifs occur. Both massifs and isolated hills contain deep flat-floored depressions, known in Malaya as Wangs, and are riddled with cave systems.

This type of scenery has been termed "tower karst". It is extensively developed in the tropical and sub-tropical parts of southeast Asia (Wissman 1954) and a similar karst topography occurs in Cuba and other parts of the Caribbean (Lehmann 1954). The development of this form of karst thus appears to be controlled by external climatic factors and not by structural features of the limestone. "Tower karst" represents a late stage in the erosion of a limestone upland when a large part of the area has been razed level with the bottom of the major valleys and the drainage is mainly sub-aerial.

The origin of the Malayan limestone hills has recently been discussed by Paton (1964). He concluded that they are the result of sub-aerial erosion in which rivers and acidic swamp water have played a major part in dissolving the limestone, although in Perlis, Langkawi and possibly also in the Kinta Valley marine erosion in the geologically recent past has modified the form of these bills. I am in general agreement with this explanation but would like to stress the role of underground water and the abrasive action of solid particles, carried in surface and underground streams, in eroding the limestone .

.. Dept. of Geology, U niversity of Mala ya, Kuala Lumpur.

Malay. Nat. J. 19 (1): 4- 12.

Figure 1. ~,' 103 '

THE NORTHERN PART OF

MALAYA Show ing the Distribution of Limestone Hills

"

"

"

WangTangga ,~ Kota ..ln

=~ KorAl! :~ ~~ ~;~r vv~.,.~ Gunong K.,..oong

~~~~ ~ ~= :~:bun ~~ ::: •...... : KI(1 t(l VOlley 22 Batu 80loh

9 Gvnong Jasek

10 8<Jkl\ lakun 24 Goo PM,ngct ~ ... '1 Botu Cove$ 2!l Uu Kenyom "10

128uk'tCh;n\amani 26 Buk'tHongus ~ ." 13 Gl.'CIKecn,' 27 Svkit8,won ~

, _ _ ,_. _~_o_oog __ s,_o'_'m __ ~'W~' ________________ -T'~O" __ ~ K~IQLU~' ____ ~~ ______ l-~ __________ ~~'~ _______ ~ __________ ~'~'~' __ ~

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6 MALAYAN NATURE JOURNAL

Erosive Features of the Caves

Most, if not all, the limestone hills probably have explorable caves. Water filled caverns below the water table possibly also occur beneath both the hills and the surrounding plain.

The air filled cave systems are similar to those described from Sarawak and Sabah by Wilford (1964). The massive recrystallized limestone in which they occur has a low porosity and is impermeable to water. However, it contains planes of weakness parallel to the original surface of deposition of the limestone (bedding planes) and joint planes typically forming two sets at right angles to each other and at right angles to the bedding. It is in these planes that water can move through the rock and in which cave systems originate. Theoretically a cave system would thus consist of a rectangular frame­work of passages. In most Malayan caves horizontal passages are more extensive than vertical or steeply dipping ones. The main passages are in places enlarged to form high, domed chambers (e.g.

the Great Room of the Dark Cave, Batu Caves) which may contain openings to the surface in their walls or roof. Such chambers may occupy the greater part of a small hill which is then merely a hollow limestone shell. The north end of Bukit Charas, in east Pahang, is of this nature. Underground streams may occupy the main passages of caves in the larger limestone massifs, e.g. in northwest Perlis. They are generally absent in the more isolated limestone hills but these commonly show signs of the former presence of streams (PI. I).

Smaller passages may run parallel to the main passage and end blindly or be open at both ends. Other blind passages lead oft approximately at right angles from the main passage and commonly are steeply inclined because the joint and bedding planes of Malayan limestones are frequently steeply inclined , due to the tilting or folding of the rock mass. The floors of cave passages are typically uneven. This is partly due to secondary deposits but often the bedrock also

' has an irregular surface and shows no grading of longitudinal profile as would be expected along a stream bed. The roof is also highly irregular, with cavities and limestone pendents. Smaller, smooth, symmetrical cavities called scallops by Wilford (1964, p. 19) are common on the walls and roof and are often used by bats as resting places. Horizontal grooves cut in the sides of a cavern, usually in the lower half or at floor level, indicate the former presence of a stream meandering through the cave and may be associated with deposits of mud and sand and ripple-like etchings o.f the limestone surface (current scallops of Wilford 1964, p.21).

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VOL. 19. MAY 1965

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FIG. 2

Section through caves at the base of Gunong Tasek, north of Ipoh . (M : marine notches; W: freshwater (running) grooves ; S : s w amp (stagnant) grooves.) (from Paton. 1964).

Rock Shelters and Cave Entrances

Many Malayan limestone hills are undercut around their bases. Various types of notch or groove have been described from the Kinta Valley and the Kedah-Perlis plain and their origins considered (Walker 1955, p. 20; Paton 1964. p. 143). Paton's text figure 4 and his plate 8 are reproduced here (fig. 2 & PI. II) . Wide arcuate notches with a scalloped roof are attributed to marine erosion and may be compared with marine notches forming at the present day around limestone islands in Langkawi. Narrower grooves were probably formed by streams cutting laterally in the process of widening their valleys. and deep narrow slits by the solvent action of stagnant acid swamp water. These undercuts may modify the entrance to caves or form rock shelters independent of cave systems. They may be partly or wholly curtained off by dripstone deposits (see below) or by rock falls from above. In the latter case the fallen blocks may become cemented by dripstone. At Gua Kechil . near Raub. Pahang. a cave passage running around the base of the hill is formed largely in this way.

8 MALAYAN NATURE JOURNAL

Cave Deposits

A variety of deposits are found in caves, partly blocking the passages and occasionally entirely filling them. Solution of the lime­stone leaves behind the small amount of impurity it contained, and this accumulates to form a residual deposit of clay on the floors of the passages. The erosion of caves also leads to the gravitational collapse of parts of the roof. and fallen masses of limestone are common in the larger caves. Underground streams deposit clay, sand, and gravel derived from areas beyond the limestone outcrop. Extensive cave systems in the limestone massif of northwest Perlis were filled with tin-bearing river alluvium which is now being mined and the cave systems re-excavated (see Jones, this issue).

Secondary calcite occurs as deposits of dripstone, flows/one and rimstone. Dripstone is a convenient term for the pendent stalactites, stump-like stalagmites, pillars formed by the fusion of these, and thin curtain-like sheets of calcite, all of which are formed by dripping water. Flowstone deposits are smooth or rippled sheets of calcite deposited on the walls and floors of caves by running water, and rimstone is a similar encrustation of calcite formed around pools of water by precipitation of calcite from a water film slowly spilling over the side of the pool. A fine example of rimstone can be seen in the underground passage leading from Wang Tangga to Kaki Bukit in Perlis (PI. I). All of these secondary calcite deposits are precipitated from ground water which, by loss of carbon dioxide to the cave air, cannot retain in solution the calcite it dissolved in its passage under­ground. Precipitation from dripping ground water may also be accelerated by evaporation if the cave air is sufficiently dry.

Deposits of guano produced by large numbers of bats and, in some caves, by swiftlets are found in most Malayan caves and these are worked extensively for fertiliser. Beneath the guano, the limestone is often partly replaced by calcium phosphate to form rock phosphate.

Theories of Cave Formation

The formation of caves in limestone was for a long time vaguely explained as due to the solution of the limestone (corrosion) by carbonated ground water and to the development of underground river systems which further erode the rocks with solid particles carried in the water current (corrasion). The fact that many caves are now dry was explained by a postulated lowering of the water table resulting from climatic changes or local uplift of the cavernous limestone.