Zoo Biology 4:219-223 (1985)

RESEARCH ARTICLES

The Species Survival Plan and the Conference on Reproductive Strategies for Endangered Wildlife William Conway

New York Zoological Society, Bronx, New York

The application of advanced reproduction technology to the breeding of vanishing species in captivity, as planned by the Species Survival Plan (SSP) of the American Association of Zoological Parks and Aquariums, may be crucial to practical long- term propagation of some species. However, current techniques are usually spe- cific to domestic animals and man. Major modifications and new approaches, on a species-specific basis, will be required for broad application to specialized wild animals. Prerequisites include basic studies of unique species’ physiology and basic care requirements. The current SSP program needs a major research component.

Key words: Breeding technology, conservation, endangered wildlife, reproduction, Spe- cies Survival Plan

INTRODUCTION

The Conference on Reproductive Strategies for Endangered Wildlife is related directly to the Species Survival Plan of the American Association of Zoological Parks and Aquariums, a plan designed to strengthen and coordinate zoo efforts to preserve vanishing species [Conway, 19821: Broadly, the conference reaffirmed the need for concerted scientific attacks upon the problems of reproducing vanishing species in captivity. Specifically, the confererice provided an update on the status of reproductive science with domestic species and recent applications to wild animals. SPECIES-BY-SPECIES APPROACHES

Hopes for a rapid acceleration of the propagation of rare species through new reproductive technologies and consequent species security were not supported by conference papers. Today, artificial breeding techniques for mammals are based on decades of research on thousands of domestic animals through scientific protocols supported by the millions of dollars available to agribusiness. Much of the technology is cow-specific-more Roy Rogers than Buck Rogers. In contrast, zoo reproduction scientists face a research struggle against the odds of inadequate samples of animals and inadequate support compounded by their often delicate subjects, which are almost infinitely specialized and exceptional. The necessity for a species-by -species approach was emphasized and reemphasized.

This paper was received for publication in the 1984 Proceedings of the Cincinnati Conference on Reproductive Strategies for Endangered Wildlife. Due to an office error it was omitted from the Volume 3, Number 4 issue of ZOO BIOLOGY. The editorial office regrets the error.

Adbess reprint requests to William Conway, New York Zoological Society, Bronx, NY 10460.

0 1985 Alan R. Liss, Inc.

220 Conway

Among the sobering observations of conference speakers were accounts of repeated failures not only in sophisticated (and not so sophisticated) efforts at inter- and intraspecies embryo transfer but also in “simple” artificial insemination (AI). Conference biologists noted that successful sperm storage techniques may vary be- tween, for example, crane species even of the same genus (Grus); that capacitation of sperm can present species-unique problems; and that gaining a basic understanding of the reproductive cycles of creatures as different as giant pandas (Ailuropodu meluno- leucu) and elands (Taurotrugus oryx) is complex science. Consequently, many current sperm bank efforts may be useless for reproduction. It is “not enough to just put sperm in a freezer and call it a ‘frozen zoo’.’’

This conference concentrated on mammalian reproductive technology. There were no significant contributions concerning reptiles and few on birds. This is an understandable focus for a meeting of this size and brevity, but regrettable. Specialists in particular animal classes have much to learn from one another. Thus far, the only effective uses of “hi-tech’’ reproductive techniques for the benefit of vanishing species have been with cranes (Gruidae) , waterfowl (Anatidae) , pheasants (Phasianidae) and birds of prey (Falconidae, Cathartidae) where artificial incubation and A1 techniques have been applied. Recent investigations of seasonal temperature control and the effect of varying incubation temperatures with various reptiles are deserving of broader scrutiny [eg, Lazlo, 19791. Indeed, the improvement of captive management in the broad sense as the first prerequisite for serious long-term wild-animal propa- gation programs was an often unstated assumption in the presentations of conference speakers [see Benirschke et al, 19801. It needs to be stated, repeatedly.

THE NEED FOR IMPROVEMENTS IN BASIC CARE

In speaking of Siberian tigers (Panthera tigris altaicu), one speaker noted correctly that “producing young in zoos has become a trivial exercise of zoo science for many species. ” However, for many more, including a disproportionate number of vanishing species, it has not.

An adequate knowledge of nutrition, disease, social and behavioral require- ments, environmental needs, and physioIogica1 norms is extremely rare for zoo species unrelated to domestic forms. Simply increasing the rate of survivial of young would do a great deal for many species with critically low populations-the okapi (Okapiu johnstoni) and some of the langurs (Pyguthrix, Nasulis) for example. Entire families of birds have not yet been satisfactorily maintained, much less bred in significant numbers. Of the 433 endangered avian taxa [King, 19811, only 37 were bred in captivity, and only 17 produced 25 young or more, according to the 1979 International Zoo Yearbook census [Olney, 1981; see also Muller, 1982; Conway, 19831. It seems that the advancement of artificial reproductive strategies for many species will have to wait for advances in the basic job of learning to care for wild animals better. Why, then, is there so much zoo interest in artificial reproduction technology, even for that growing group of creatures for which breeding has become a “trivial exercise”? The principal reason is lack of space.

THE IMPLICATIONS OF ADVANCED REPRODUCTIVE TECHNOLOGIES

Zoos have so little room, only about 20,000 acres in the United States including all space devoted to administration and visitor facilities [Wagner, 19831, that they are

Breeding Technology and the SSP 221

unable to provide for large, secure populations of more than a few species. Besides the worry of catastrophic disease, accidents, and the like, zoos must contend with the potential for genetic and demographic problems in their small, isolated populations. By contrast, the rich reproductive technologies now in common use with domestic animals by the species-poor agribusiness, as set forth at this conference, can only be seductive to the species-rich, technology-poor zoo conservationist.

Examples of exciting reproductive technologies now possible or nearly so with one domestic species or another as set forth at this conference, and some of their implications for the preservation of endangered species in captivity, should ways be found for their general application to zoo animals, include these:

Techniques

Long-term sperm, ova, and embryo storage with a reliable technology of artificial insemination and embryo transfer to surrogates of related animals could result in 1) acceleration the propagation of a species or genetic line, 2) security for the preservation of original genetic diversity and consequent protection against in- breeding, and 3) maintenance of part of species population in storage, permitting care of more species in limited zoo space with major cost savings.

Egg and embryo micromanipulation developments, including embryo splitting and transfer, embryo sexing, and egg enucleation with replacement of nuclear mate- rial could result in 1) acceleration of propagation of a species or genetic line, 2) rescuing a species where only one sex is available, and 3) improvement of genetic and demographic management control.

Research Priorities Although contemplation of the theoretical potentials of gamete banks and em-

bryo manipulation serves a heuristic purpose, the paths toward their realization in zoo breeding will be long, costly, and indirect. For many endangered species, they are unlikely to be realized or will come too late. The Cincinnati conference was a working get-down-on-details meeting. From the standpoint of AAZPA-SSP, its special values were in its facilitation of information exchange, the identification of immediate research priorities, and of some of the researchers working in related areas. Except for ethological and genetic priorities, which have been presented more often at past meetings, those mentioned most frequently may be summarized under three headings:

Establish the normals. It is essential to accelerate the development of the techniques and the practice of monitoring reproductive cycles. Unless baseline data are available, the technologies of artificial breeding will not be useful whether they be artificial insemination, embryo trnasfer, or even, in some instances, putting males and females together. An understanding of normal physiological and endocrine cycles is necessary for comprehension of the conditions required for fertilization and for further development of the techniques of reproductive cycle control, stimulation, and synchronization [see Lasley, 19821.

Pursuant to the understandings gained from the studies of domestic animals and man, develop species-specific technologies. Successful species-specific tech- niques for gamete and embryo storage, AI, embryo transfer, sperm collection, evaluation, equilibration and capacitation, and even species-specific cryoprotectants pose difficult, often empirical investigative tasks. It is clear that this work will be best and most economically done in connection with research groups already working with domestic animals and man. Such zoo research group affiliations, be they academic,

222 Conway

governmental, or commercial, will also provide for essential training opportunities. Besides, it is comforting to reflect upon the fact that, in this effort, man will often be a research model for the monkey.

Treat the research populations with sensitivity. Already much progress has been made in the development of noninvasive technique, particularly in physio- logical evaluations. In reproductive technology, even mouse embryos have been collected nonsurgically. Few zoos permit invasive research except for the welfare of the concerned species itself. Reproductive studies on endangered species meet that criterion, but they also increase the investigator’s obligation to broaden the use of noninvasive methods and to elaborate the use of anesthetics and ways of handling wild animals safely. All of this, too, must be approached on a species-by-species basis and in response to ongoing evaluations of possible stress and its effects.

CONCLUSION AND PERSPECTIVE

Until the 1960s, zoo animal management research was devoted mostly to problems of individual animals: the tasks of teaching a “difficult” new bird to eat a substitute ration, purging the parasites of a particular reptile or herd of ungulates, or getting a particular pair of animals to breed. Then, new medicines and veterinary techniques as well as curatorial management of enclosures began to relieve zoo biologists of some basic worries. They became aware of the opportunity to apply newly available information from the young sciences of ethology and ecology and from studies in both the laboratory and nature. The character of newly constructed zoo exhibits began to respond, for a new exhibit technology was also taking shape. More “natural” exhibits became an objective, both visually and in terms of the social and environmental opportunities they presented to their inhabitants. Animals began to be kept in larger social groups. An awareness of the diminution of wildlife, of the impending extinction of some faunas en masse, began to dominate the concerns of thinking zoo biologists, and some insisted that long-term reproduction of species populations had to replace zoo stamp collections of individual animals. With this development, a past-due awareness of the zoo world’s failure to manage its breeding animal populations genetically or demographically became apparent. Moreover, the precepts for rational genetic management were already available and usually applica- ble in general rather than only in species-specific ways. Any zoo curator could contribute to the welfare of his collections through attention and collaboration with his colleagues in the zoo world.

Concerted collaboration between zoos in a planned strategy is the key to genetic management, for no one collection can sustain large enough populations to do the job alone. Inevitably, the AAZPA Species Survival Plan-a plan to manage rare animals as national populations, not just as individual zoo populations-was born. With its advent, zoo care biology has come full circle to renew its focus on the problems posed by the health and breeding of individual animals and on “difficult” species whose maintenance and reproduction have not proved a “trivial exercise.” This time, however, there is a potential to proceed with powerful new diagnostic tools and reproductive technology.

The problems of sustaining difficult species on the one hand and of the manage- ment of prolific animals for which there is inadequate space on the other are the underlying and continuing stimuli for meetings such as this. Their most serious implication for the AAZPA-SSP program managers is a further elevation of the level

Breeding Technology and the SSP 223

of complexity in the tasks facing these volunteer groups. For SSP, the main message of this conference is that the development of effective “reproductive strategies for endangered wildlife” will often depend on concerted multidisciplinary scientific attack, on work by reproductive specialists rare in the zoo field. At present, few Species Survival Plan propagation groups are equipped to undertake such an attack. The planned addition of a scientific council to the SSP program may respond to this lack.

REFERENCES

Benirschke, K.; Lasley, B.; Ryder, 0. The tech- nology of captive propagation, pp. 225-242 in CONSERVATION BIOLOGY. M.E. Soule; B.A. Wilcox, eds. Sunderland, Maine, Sinauer Asso- ciates, 1980.

Conway, W.G. The Species Survival Plan; tailor- ing long-term propagation species by species, pp. 6-11 in AAZPA 1982 ANNUAL CONFER- ENCE PROCEEDINGS. Oglebay Park, West Virginia, AAZPA, 1982.

Conway, W.G. Captive birds and conservation, pp. 23-36 in PERSPECTIVES IN ORNITHOL- OGY. A.H. Brush; G.A. Clark Jr., eds. Cam- bridge, Cambridge University Press, 1983.

King, W.B. ENDANGERED BIRDS OF THE WORLD, THE ICBP BIRD RED DATA BOOK. Washington, Smithsonian Institution Press, 1981.

Lasley, B.L. Current endocrine research on zoo animals, pp. 143-145 in AAZPA 1982 ANNUAL

CONFERENCE PROCEEDINGS. Oglebay Park, West Virginia, AAZPA, 1982.

Lazlo, I. Notes on reproductive patterns of reptiles in relation to captive breeding. INTERNA-

Muller, K.A. Observations on the 1981 Bird Breeding Survey, pp. 365-375 in AAZPA 1982 ANNUAL CONFERENCE PROCEEDINGS. Oglebay Park, West Virginia, AAZPA, 1982.

Olney, P.J.S. Birds bred in captivity and multigen- eration births 1979. INTERNATIONAL ZOO

Wagner, R.O. The private and the public avicul- turists, pp. 11-15 in PROCEEDINGS, JEAN

ING BIRDS IN CAPTIVITY. North Hollywood, California, International Foundation for the Con- servation of Birds, 1983.

TIONAL ZOO YEARBOOK 19122-27, 1979.

YEARBOOK 21:271-304, 1981.

DELACOURlIFCB SYMPOSIUM ON BREED-