Captive Management of Breeding Asian Elephants

By Jay Haight Washington ParkZoo, Portland, Oregon, USA.

I Perspective: for Elephants can be summarized in one word: staff. Although we need additional trained A large captive breeding herd of endangered personnel to work among our Elephants, the Asian Elephants has been managed for over a fact remains that our Elephants and our pro- quarter of a century at Washington Park Zoo. gram have enjoyed relatively great stability During this time, twenty-four calves have been in this regard. Our veterinarian has been with born, and the twenty-fifth birth is expected in us for over 17 years, and spends time each October of 1991 . day with the Elephants and staff. Of the four keepers on the Elephant management team, The success of Washington Park Zoo in none has less than some 6.5 years of ex- regard to Elephant propagation is rooted in perience with our animals and our facility. several easily understood factors. One factor To put it in different perspective, our Elephant of major importance is the facility itself; al- management team has accumulated over 67 though by no means perfect for Elephants, man-years of experience with Washington our facility has been designed and constructed Park Zoo's animals; providing a considerable such that housing and care for both sexes of base from .which to draw as our Elephant Elephants can be provided with a high degree management program continues to evolve. of safety, Evolution did not design Elephants to be chained for hours each day, but as Ele- Finally, we are fortuitously located in proxi- phants can, in a sense, be regarded as "intelligent mity to several scientists of high calibre, who bulldozers", chains have long been employed share our interests in Elephant biochemistry as means of ensuring that unsupervised animals and reproduction, and who willingly donate do not destroy their "house". Because of the their time, expertise, and even their money dangers associated with daily chaining of adult in pursuing these topics with us. Thanks to bull Elephants, the great majority of zoos them, we have been able to elucidate the oes- chose not to house them; those that have trous cycle of the Asian Elephant, to pursue a attempted to maintain adult bulls under such directed approach to artificial insemination circumstances have often paid the price - human for Elephanb, and to investigate such pheno- lives. mena as chemicalcommunication and musth.

Recognizing these facts, Washington Park Although much remains to be learned in Zoo built a unique facility - more or less "Ele- regard to Elephants, we know much more now phant proof". This eliminated the necessity for than has been known before. long-term chaining, afforded safer means for O handling Elephants, and permitted flexibility in our approach to Elephant management. As THE OESTROUS CYCLE a result, we have been able to house three adult bull Elephants, as well as a number of cows. Since Asian bult Elephants are solitary by Moreover, our hydraulic Elephant crush, added nature, it is reasonable to maintain captive bulls onto our facility over a decade ago, allows in that condition, rather than force them to us to provide needed medical and maintenance socialize with a herd of cows at all times. How- care for the bulls, in the safest possibte manner. ever, , this management r approach presents a dilemma; in order to breed the Elephants, one Another faetor of importance to the must be able to introduce the bull.to a cow Washington Park Zoo's management program at the proper time. Contrary to some published

21 reports, cows generally do not exhibit out- Our data (7,8) have conclusively demonstra- ward signs of estrous; our cows at lease, don't ted that the oestrous cycle for Elephants is engage in an "oestrus walk" nor croon "come much longer than previously imagined. hither" so.ngs (infrasonic or otherwise); But Dr Michael Schmidt, our veterinarian, was struck by a description of bull Elephant beha- BIRTH viour which led him to suspect that bulls might, by chemical mearis, be able to detect the oestrus The gestation period for Elephants is bet- status of cows. An experimental assessment ween 630 and 660 days. of this theory was therefore launched. Promptly dubbed "the Sniff Test" it involved backing Perhaps because of the time-frame involved, a cow - on a daily basis - toward the door many zoo staff seem to forget that birth is of a room housing a bull, opening'the door a natural phenomenon. Elephant cows live in a metre width, and allowing the bull to "check" herds. They give birth. This is a normal part of the cow. lt was determined that the bull could Elephant life. The only abnormal aspect, here, indeed discern the status of the cow - but is that of life in captivity. lt is unreasonable, this finding raised other questions. even inhumane, to isolate a gregarious animal such as an Elephant cow. Unfortunately, that The ieaction of the bull to a cow in heat is the first step taken by many zoos preparing was unmistakeable, but weeks and months for an Elephant birth. In general, this approach would go by with little or no reaction. imposes undue stress upon the cow, and should be avoided. For many years, it was accepted as fact that the oestrous cycle of the Elephant was On the other hand, inexperienced animals 18 to 22 days in length. What published lite- may feel threatened by the sudden appearance rature was available (1 ,2,3) agreed that such of an interloper (in this case, a newborn calf), was the case, and subsequent publications therefore, it is reasonable to secure these animals (4,5,6) supported that position. Our bulls' by meahs of leg restraints, provided that this feactions were not in accord with the pre- process is begun well in advance of the,projected vailing view. time of parturition. Since birth is a normal part of Elephant life, you must ensure the Ele- ln an attempt to correlate observed beha- phants' comfort within a "business as usual" viour with biochemistry, and in blissful ignor- format. ance of the established fact that it was impos- sibfe to do so, WPZ Elephant management At WPZ a strict "business as usual" protocol staff began drawing weekly blood samples is maintained; during normal visitor hours, from our cows. In time, it became apparent visitors are present. During non-visiting hours, that progestero.ne levels showed a perfect only Elephant management staff are present - inverse correlation with the relative level of mucking out the area as usual, feeding as usual interest exhibited by the bull tovards a cow; etc. Since our Elephants are used to staff inter- as P4 levels increased, interest declined - and action at all hours of the day or night, it truly vice versa. This phenomenon suggested that is "business as usual" as far as they are con- the oestrous cycle was not in accordance with cerned. that described in the literature, but was many times longer in duration; approximately 16 During the past few years, however, a weeks long, in fact. Using this information, number of problems involving parturition it became possible to "time" matings. We'have and first-time mothers have surfaced at insti- for example, put a bull and a cow together for tutions in the United States and in the United less than 10 minutes on one (and only one) Kingdom. Specifically, problems have occurred day - and achieved conception. at Tulsa, Oklahoma, San Diego, : California,

22 and Syracuse, New York (all USA) and at Port trunk, and will use her.trunk and frqnt feet in Lympne, UK. spirited attempts to get the calf up and onto its feet. Generally, the excited mothef ends up In Tulsa, the mother gave birth to a healthy knocking the calf over several times, as the calf calf, but would have nothing to do with it. Re- struggles to balance on round feet arid unsteady qa cently a similar event occured in San Diego. In legs. ?r both cases, an apparently healthy animal gave birth to, then rejected, a healthy and normal Normally, a mother does not kick the calf calf. Given more appropriate facilities, it seems with her hind feet; although her excited likely that these problems might have been attempts to induce the newborn calf to rise overcome. may appear rather rough, they involve only the front feet and the trunk. Clearly, a clean substra- With regard to an event in San Diego, and te, capable of providing good traction, will be events in Syracuse and Port Lympne however, helpful to the calf in its efforts to stand. As soon the problems arose prior to parturition. ln each as possible, it is wise to sterilizer the calf's case, a first-time mother was unable to deliver umbilicus with a solution of strong iodine. the calf. ln most cases, both mother and calf were lost (Port Lympne was fortunate, this year, The placenta and amniotic sac will not or- in that the cow survived in good condition). dinarily be consumed by the mother. We may hypothesize that physical condition and/or diet may play a role in these events. We can be relatively certain, however, that if COW-CALF MANAGEMENT the calf can be extracted within 24 hours of the time amniotic fluids are drained, its chances for In our experince, the training process can survival will be enhanced. begin for calves within a few months of birth' It is both possible and desirable to entrain basic The importance of ensuring that a team of management behaviours without removing the Elephant specialists can be quickly assembled calf from its social group. In this environment, cannot be overemphasized, where first time however, the option of force is severely rest- mothers are concerned. When informed ricted. Cows are generally very protective of decisions must be made quickly, any delay calves; instinctively rushing to their defense at increases the odds .against a desirable outcome. any sign of trouble. While it is important to maintain a "business as usual" approach, it is A normal birth sequence follows this general equally important that any new procedure pattern; the cow passes a large rubbery blob of (such as working with the calf) can be imple- mucous (the cervical plug). Within one to five mented with caution, in order to minimize the days following this event birth occurs. Signs possibility of arousing a defensive response of impending delivery include frequent shifting from the rest of the herd. of position by the uncomfortable cow, squirting of colostru m fro m en larged breasts, some This is not an insurmountable problem how- bleeding from the urogenital area, and finally ever, and we have trained calves to willingly a prominent lump below the tail. When the accept leg-chain restraint by the time they have cow goes into hard labour, the calf is normally reached seven to eight months of age. In a sense, delivered rear feet first, and very quickly. training calves within the context of their natal herd can facilitate the training process by lf the calf's mouth and trunk are covered by surrounding the calf with role models. The amniotic sac, it may be pulled away. Ordinarily, dominance hierarchy associated with herd struc- a calf will stand within five to fifteen minutes ture doubtless helps, as well; since Elephants of birth (though it seems considerably longer establish and maintain a dominance hierarchy, at the time). Under normal conditions, a mother and since this hierarchy is predicated upon phy- will frequently contact the new born with her sical force, dalves learn their position in the

23 dominance structure at a very early age. The less responsive, more domineeringr.and generally handler must, in order to work safely and truculent. Other herd members begin to show effectively among the Elephants, occupy the less tolerance for the young male. In the wild, topmost position in the dominance hierarchy, the young bull would eventually be driven from a! and the calf clearly understands position its in the herd. In captivity, the handlers must remove j relation to that of the handler. Thus the handler him. rt is able to begin the training program from a posi- tion of relative strength, and by extensive use of positive reinforcement, can elicit from the In the wild, the young bull may hang out on calf both a desire to cooperate - and its trust. the periphery of the herd for some time - per- haps one to two years - before establishing a solitary In management of Elephant cows and territory for himself. In captivity, it's calves, getting them to trust you and gaining pretty much an all or nothing affair. This their cooperation are the two most important raises some interesting problems. tools available to the handler - and all too often, the least used. Elephants have big ears, The young bull has been tractable all of his and excellent hearing. Yet we've all encountered life, and is tractable now. This circumstance handlers who yell commands Elephants at the allows handlers to bull themselves into believing in their charge, and handlers who seem a bit that they' may possess some unique quality overzealous in their use of the hook. As my which enables them to work with bulls. lt is senior partner, Roger Henneous, has noted, important to realize that Elephants kill more "The number people who honestly believe of personnel than all other species of animals kept that they can moke an Elephant do their bidding in zoos and circuses combined. There are is astonishing. point fact, there - In of are two many more captive cow Elephants than there things one make Elephant can an do, and are captive bull Elephants, but bulls account neither very pleasant: Elephants of them is for the majority of incidents. During the past can be made to run away, and they can be 3 ,years in North America, for example, bull made to kill (9) ... but one can get an Elephant Elephants have killed at least 4 personnel, and to do an amazing number of things". hospitalized at least 1 more. By contrast, cows have accounted for two hospitalizations In our experience, Elephants appear to (although cows have, on occasion, attacked and possess a strong sense of fairness where reward killed personnel, they are generally'much less and punishment are concerned. We find that likely to do so). In both cow incidenb, the staff immediate and consistent or undue punishment involved were inexperienc6d; whereas one of and inconsistent reward, on the other hand, the dead reportedly had 'l 8 years of experience can produce Elephants which require constant in Elephant work, and the others involved in vigilance. lt is important to note that consisten- bull incidents also had experience. cy does not imply rigidity or inflexibility. Consistency simply means "in agreement with" It is possible to work bull Elephants until the circumstance. The successful management - the moment when program for Elephant cows and calves will it becomes impossible. As Dr Schmidt has commented "Handling incorporate a high degree of flexibility. bull Elephants is like jumping off a 40.storey build- ing, and as you pass each floor saying 'so far so BU LL E LEPHANT MANAGEMENT good' the end result is always the same". ln order to provide high-quality care for these Eiephant cows and calves are highly social; dangerous animals, it is safest to condition therefore, juvenile males can be managed in a them to willingly enter a crush. Given a crush, social environment. As they mature, however, sufficient experienced staff, and time, virtually the temperament of male galves undergos a any necessary procedure can be safely and effec- subtle change, in that they become progressively tively carried out.

24 MUSTH Like humans, as Elephants age, their systems break down. Conditions of captivity may Having tracked serum, urinary and temporal accelerate. this process. Younger Elephants . gland secretion values for various hormones can seemingly survive almost anything, but throughout musth cycles, we know more than older Elephants seem increasingly susceptible s has ever been known about this phenoffi€lloll: to foot problems andlor general immune system . Regrettably, it isn't much. We don't know dysfunction. In circuses and in Zoos, when exactly what causes musth, but we know that Elephants are obliged to stand for much of it occurs in bult Elephants who are in iood the day on hard and unyielding surfaces, foot physical condition. We know that musth is problems emerge as a major pr,oblem as the characterized by significant fluctuations animals age. lt is increasingly evident that an in adrogenic hormone ratios, (10) that the aggressive program of foot maintenance must concentrations of ancillary (and presumably be pursued. This involves "round the clock" chemocommuncative) volatiles flucuate accord- waste removal, daily foot inspection, and trim' ingly (1 1) and that the process is under endor- ming of the soles and nails as necessary. crine control. We know that musth is not a rutting period, (1 2) in the classic sense of the Problems tend to start at the sole/nail term. interface. Once underway, infection seems to spread upward, via the soft tissues behind the Most likely, musth allows bull Elephants to nail, eventually erupting above the nail. In break through the inhibitions imposed by prior extreme cases, infection will migrate inward, learning experiences, and to challengo the affecting bone. established dominance hierarchy, humans be- come the target of musth bull challenges. The ideal Elephant foot lacks bulbous, Viewed in this context, the outcome is wholly protruding nails, and has a smooth sole predictable; when the handler is obliged to lacking flaps and divots, which provide ideal work directly with a bull Elephant, that handler homes for bacteria and fungi. will eventually be iniured or killed. This is nor- mal and expected behaviour for bulls; therefore, Zoonoses (in this case, human-vectored where bull Elephants are kept, facilities that diseases) may also influence the longevity of are able to contain bulls and to permit safe per' captive Elephants. Where the general public formance of routine management procedures is permitted to contact either Elephants or are mandatory. their captive habitat, the possibility of disease transmission exists. Elephants are susceptible to human tuberculosis and diptheria, for exam- GERIATRICS AND ILLNESS ple. lt:is therefore advisable to minimize the exposure of this endangered species to public Although a comprehensive discussion of areas, and to minimize the exposure of Elephant Elephant illness and diseases may be found habitat to the general public. ' elsewhere (13) it is helpfulfor Elephant handlers to bear in mind a few basic facts: Other known Elephant killers are anthrax, botulism and salmonellosis (often resulting ' Evolution has designed Elephants for longe- from contaminated feed), and tetanus'(iesulting vity. That is not the case for humans; until from hook wounds, generally poor environmen- the.turn of this century, the average human, tal maintenance, etc). : life span was less than 50 years. Medical in- tervention has permitted extension of the Tusk infections have also claimed the lives human life span roughly double that dictated of Elephants; most recently the bull "Tantor" by evolutionary design; by contrast, Elephants at Canada's Metro Toronto zoo. lt is important are designed for a 55 to 60 year life span under to remember that true tusks possess a pressure wild conditions. sensing nerve; the cavity of which extends

25 domineering, and generally dominanee structure at a very early age' The less responsive, more herd members begin to show handler must, in order to work safely and truculent. Other the young male. ln the wild, effectively among the E less tolerance for eventually'be driven from topmost position in the the young bull would must remove calf clearlY unde the herd. In captivity, the handlers and the t relation to that of the handler. Thus the handler him. rf is able to begin the training program from a posi' tion of relative strength, and by extensive use of positive reinforcement, can elicit from the calf both a desire to cooperate - and its trust' In management of ElePhant cows and calves, getting them to trust you and gaining their cooperation are the two most important tools available to the handler - and all too often, the least used. Elephants have big ears, The young bull has been tractable all of his and excellent hearing. Yet we've all encountered life, and is tractable now. This circumstance handlers who yell commands at the Elephants allows handlers to bull themselves into beligving in their charge, and handlers who seem a bit that they' may possess some unique quality overzealous in .their use of the hook. As my which enables them to work with bulls' lt is senior partner, Roger Henneous, has noted, important to realize that Elephants kill more "The number of people who honestly believe peisonne! than all other species of animals kept that they can moke an Elephant do their bidding in toot and circuses - combined' There are is astonishing. In point of fact, there are two things one can make an Elephant do, and neither of them is very pleasant: Elephants can be made to run away, and they can be made to kill (9) .'. but one can get an Elephant to do an amazing number of things". hospitatized at least 1 more. By contrast, cows have accounted for two . hospitalizations

1 years of experience and inconsistent reward, on the othir 'hand, the dead rbportedly had 8 in Elephant work, and the others involved in bull incidents also had experience.

It is possible to work bull Elephants - until the circumstance. The successful management ttre moment when it becomes impossible. As program for Elephant cows and calves will Dr Schmidt has commented i'Handling bull incorporate a high degree of flexibility'

BU LL ELEPHANT MANAGEMENT is safest to condition Eiephant cows and calves are highly social; dangerous 'animals, it willingly enter a crush. Given a crush, therefore, juvenile males can be managed in a them to experienced staff, and time, virtually social environment. As they, mature, however, sufjicient procedure can be safely and effec- the temperament of male palves undergos a any necessary carried out. subtle change, in that they become progressively tively

24 MUSTH Like humans, as Elephants age, their systems break down. Conditions, of captivity may Having tracked serum, urinary and temporal accelerate this process. Younger Elephants gland secretion valubs for various hormones can seemingly survive almost anything, but throughout musth cycles, we know more than older Elephants seem increasingly susceptible I has ever been known about this phenomenon. to foot problems and/or general immune system tl Regrettably, it isn't much. We don't know dysfunction. In circuses and in Zoos, when exactly what causes musth, but we know that Elephants are obliged to stand for much of it occurs in bull Elephants who are in good the day on hard and unyielding surfaces, foot physical condition. We know that musth is problems emerge as a major problem as the characterized by significant fluctuations animals age. lt is increasingly evident that an in adrogenic hormone ratios, (10) that the aggressive program of foot maintenance must concentrations of ancillary (and presumably be pursued. This involves "round the clock" chemocommuncative) volatiles flucuate accord- waste removal, daily foot inspection, and trim. ingly (1 1 ) and that the process is under endor- ming of the soles and nails as necessary. crine control. We know that musth is not a rutting period, (1 2) in the classic sense of the Problems tend to start at the sole/nail term. interface. Once underway, infection seems to spread upward, via the soft tissues behind the Most likely, musth allows bull Elephants to nail, eventually erupting above the nail.'ln break through the inhibitions imposed by prior extreme cases, infection will migrate inward, learning experiences, and to challengo the affecting bone. established dominance hierarchy, humans be- come the target of musth bull challenges. The ideal Elephant foot lacks bulbous, Viewed in this context, the outcome is wholly protruding nails, and has a smooth sole predictable; when the handler is obliged to lacking flaps and divots, which provide ideal work directly with a bull Elephant, that handler homes for bacteria and fungi. will eventually be injured or killed. This is nor- mal and expected behaviour for bulls; therefore, Zoonoses (in this case, human-vectored where bull Elephants are kept, facilities that diseases) may also influence the longevity of are able to contain bulls and to permit safe per- captive Elephants. 'Where the general public formance of routine management procedures is permitted to contact either Elephants or are mandatory. their captive habitat, the possibility of disease transmission exists. Elephants are susceptible to human tuberculosis and diptheria, for exam- GERIATRICS AND ILLNESS ple. lt is therefore advisable to minimize the exposure of this endangered species to public Although a comprehensive discussion of areas, and to minimize the exposure of Elephant Elephant illness and diseases may be found habitat to the general public. elsewhere (13) it is helpfulfor Elephant handlers to bear in mind a few basic facts: Other known Elephant killers are anthrax, botulism and salmonellosis (often resulting Evolution has designed Elephants for longe- from contaminated feed), and tetanus (resulting [' vity. That is not the case for humans; until from hook wounds, generally poor environmen- the turn of this century, the average human, tal maintenance, etc). : life span wab less than 50 years. Medical in- tervention has permitted extension of the Tusk infections have also claimed the lives human life span ro0ghly double that dictated of Elephants; most recently the bull. "Tantor" by evolutionary design; by contrast, Elephants at Canada's Metro Toronto zoo. lt is important are designed for a 55 to 60 year life span under to remember that true tusks possess a pressure wild conditions. sensing nerve; the cavity of which extends

25 we need the help of our organizational approximately one third of the distance of the them, general tuik's length, measuring from the sulcus out- managers and the Public- tusk wear often occurs in cap- ward. Unusual Neither will support that which they do can be ameliorated by Protecting tivity. This understand, nor will they support things by banding with a malle- not the iusks; for example, cannot feel good. In order t the event that the about which they able metal such as brass. In compelling, to iustify action, managers require I , nerye cavity is penetrated, infection wi!l occur; and unbiased, information. lf we are to motivate is imperative that provisions for therefore, it people toward the cause of preventing extinc- and effective daily treatment be allowing safe tion of entire genera, we need do only three available. things, we must show our concern, we must provide reliable information, and we must be to work with other END NOTE able PeoPle. our concern by how we inter- i From a management perspective, then, We can show with the animals in our care, and by how we it is clear that the most effective means of act \ interact with the human animals not in our care' Provision of reliable information requires the available knowledge bases familiarity with I in regard to captive Elephant management, the biology of wild Elephants. This involves I intensive training of animals and staff, and and effort, as questionable oi erroneous financial investment. In other words, they considerable theories are often presented as commitment commitment of resour- notions and require - hard, reproducible, and reliable ftot the organization as a whole, and fact. Cold, .., date are often hard to come by, and even these may be subject to varying interpreta- tions, as illustrated by the available literature which describes musth.

Working with other people may be among the most difficult of our challenges; as it re- quires that we abandon our reflexive black or white, offense or defense approach in favour of a shades of grey, compensatory, how can we move toward the ultimate goal approach. As *ith working among Elephants, flexibility, circumspection, and patience are key'ingredients support. that will likely help all to achieve the desired goal. helps me to reflect that, while I have Because we work directly among Elephants, lt of people'whom I consider to everything we do with them involves a degree met a number in their chosen endeavours, none of calculated risk. Because we spend a large be "experts" portion of our time in relatively dangerous have ever represented themselves as such. They just do the best work theY can. circumstances, we tend to develop what others , may perceive as "an attitude"- Though largely . Washington Park 7a, I thank aeflniive in formulation and application, this On behalf of this time, and hope that "attitude" is counterproductive, when viewed you for allowing me range of commu- in the larger context of our cause; whether it serves to stimulate a broader international basis, in regard we work with Asian or African Elephanfs, we nication, on an work with dying genera. In order to preserve to captive ElePhant management.

26 ACKNOWLEDGEMENTS 6. .'E D Ramsay, B L Lasley, G H Stabenfeldt. 1981. Monitoring the Estrous Cycle of the I thank Roger L Henneous and Dr Michael Asian Elephant. (Elephos maximus) Using J Schmidt for sharing with me their insights Urinary Estrogens. Am J Vet Res a2 Qlz and their knowledge. I also thank Mr Henneous 256-260. a for providing me a second lease on !ife, and a l. seemingly inexhaustible and ongoing colour 7. M J Schmidt, D L Hess, A M Schmidt, R L commentary. Henneous, D A Groves, J D Haight. 1981. The Estrous Cycle of the Asian Elephant. The management of Washington Park Zoo Proc. American Assn. Zoo Yet (1981):91- have been most supportive. WPZ Director, Y. 95. Sherry Sheng, General Curator, Dennis Pate, and Assistant Curator, Michael Keele have 8.' D L Hess, A M Schmidt, M, Schmidt, 1983. worked together to allocate scarce resources, Reproductive Cycle of the Asian Elephant including time and manpower, in order to ensure (Elephos moximus) in captivity. Biol. Re- my participalion here. prod.29 @l:767-773. Transportation funds were graciously pro- 9. R L Henneous. M J Schmidt, J D Haight, vided by FOZ (Friends of the Zoo) and are 1987. Deadly Dilemmasof Captive Elephant greatly appreciated. Breeding. in: AAZPA National Conference Proceedings. Finally, I thank Martin Smith and Neil

Spooner for their efforts in providing this 10. L E Rasmussen, I O Buss, D L Hess, M J opportunity. Schmidt, 19U, Test'qsterone and Dihydro- testerone Concentrations in Elephant Serum and Temporal Gland Secretions. Biol. of Reprod uction 30, 352-362. REFERENCES 11. L E L Rasmussen, D L Hess, J D Haight, 1. M R Jainudeen, J F Eisenberg, N Tilakerat- 1990. Chemical Analysis of Temporal Gland "1971. D€, Oestrous Cycle of the fuiatic Secretions Collected From an Asian Bull Efephant (Elephas maximus), in Captivity. Elephant During a Four Month Musth J. Reprod. Fert 27, 321 -328. Episode. Journ. of Chernical Ecol. 16 (7): . 2',67-2181. 2. J F Eisenberg. G McKay, M R Jainudeen, 1971. Reproductive Behaviour the of 12. M J Schmidt 1989. The Fihe Art of Ele- Asiatic Elephant (Elephos moximus) Beha- phant Breeding. Animal Kingdom 92 (51: viour 38; 3-4, 194--224. 44-51.

M R Eisenberg, 3. Jainudeen, J F J B )aya- 13. M J Schmidt 1986. Elephants (Proboscideo). singhe. 1971. Semen of the Ceylon Ele- in: Zoo and Wild Animal Medicine, second (Elephos phant, maximus) J Reprod. Fet. edition. Murray E Fowler, ed, W.B Saunders 24,213-217. Co.88L923.

4. I F Eisenberg 1980. Recent Resedrch on the Biology of the Asiatic Elephant (Elephas maximus)on Sri Lanka. Spolia Zeylanica35, t-||,2't3-218.

5. A.S.Abeyratne. 1982, Elephant Breeding - some scientific facts. Loris 16 (21:91-94.

27