These two maxims provide the premise for the conservation of theatened species undertaken by a large network of European zoos. The EEP organisation, an abbreviation of the "European Endangered Species Programme" coordinates and stimulates the endeavours towards that conservation. Threatened anirnals in zoos serve as ambassadors of nature, conveying the importance and urgency of nature conservation. Even now the very existente of a number of these species has become entirely dependent an zoos.
Nature and Nature Conservation
The earth is the house of life. We all live together on this earth: plants, animals, and people; creating an intertwining, interconnecting web of life. Only unbroken this network ensures a house where it is good to live. Each plant and animal forms a fibre and is thus important, whether inhabiting a Dutch polder, a mountain side in the Alps, or even a far away sea or desert. Every human being shares a responsibility for all other life within this web and for maintaining the livability of our house.
Nature, defined as the complex interactions between the earth and life, has not always been as we know it now. Earthquakes, floods, climatic changes, volcano eruptions and continental shifts have created an ever changing earth image, dramatically altering entire biospheres. However, nature is elastic and has a great capacity for adaptation and recovery: plant and animal species have evolved to replace those no longer suited to newly created environments. Species have become extinct; sometimes even entire groups of life forms have completely disappeared from the face of the earth.
Changes are still occurring; species and entire landscapes are still disappearing. This would seem natural, but it is not. The pace of change has increased dramatically, and alterations are now human related. Man clears forests, builds cities and highways. He pollutes the ground, air and water an a great scale, and with a frighteningly increasing speed. The balance of the systems essential to all life is disrupted, no part of the earth has been left untouched. Though nature has remarkable resiliency, she does not have time enough to recover from these blows now so quickly dealt. Not only are individual species threatened, but also our entire planet.
Nature conservation is therefore more important than ever. In the coming decennia man must determine and confront the most critical Problems and strike a new, stable balance with nature. If he is not successful in this endeavour, the face of the earth will be definitively, and irrevocably altered. Assuredly, this would not mean that our planet would be totally devoid of all life, there will always be some forms capable of surviving such a disaster. But mankind, and mang of our coinhabitants, would not in any Gase observe what remains in the new world, simply because we would no longer exist.
The role of zoos
Nature conservation begins with the things we know: the plants, animals, and landscapes around us, in our own country. Yet the interdependence of all nature has become increasingly obvious as knowledge in the field of ecology has grown. However, the problem remains that "what is unknown is unloved", thus enthusiasm for conservation of unknown entities, those plants, animals and ecosystems elsewhere in the world, can only be expected to be, at best, lukewarm. Acquaintance with unfamiliar nature in its own environment can only be made by travelling there, an option not available to many people. Even those individuals lucky enough to have such opportunities can still experience only a fraction of the whole. From the comfort of an easy-chair in one's own living room, television, books and magazines offer an opportunity to come into contact with unique pieces of nature found only in the farthest corners of the earth. Yet regardless of how well these medias present their material, the experience remains twodimensional, with limited emotional impact.
Zoos offer an alternative means by which to become acquainted with life forms from distant continents and seas; one which adds new dimensions to the personal experience. The zoo visitor not only has the opportunity to view live animals, but also to observe how they move, eat, and interact with their conspecifics. Zoo animal enclosures are more and more frequently designed to encourage animals to behave in a natural manner, but at the same time allow visitors an intimate view of the animals' life. The visitor can additionally experience animals via senses other than visual: hearing and smell. Though the segments of nature that can be experienced in zoos cannot be representative of all possible environments, they can be presented in an penetrating manner and can demonstrate the biological diversity we have an this planet.
Approximately 100,000,000 people visit the some 200 zoos throughout Europe yearly. The ready availability of the zoo network makes it possible for the great majority of people, whether young or old, rich or poor, to make a visit an a regular basis. They have the opportunity to develop a feeling for the amazing diversity of life, and the necessity of preserving the creatures they see, their coinhabitants in nature, and the environments in which they exist. Providing the public with this opportunity is the most important role that the zoo network can play in nature conservation. There is no other institution or medium that can bring home this message so forcefully to such a large number of people.
Animals for zoos
The contribution that zoos can make in nature conservation is dependant an the presentation of live animals. However, the maintenance of live animal collections is no easy task. One characteristic shared by all animals is that sooner or later they die, irregardless of the quality of care that they receive. It was a simple matter to obtain replacements for lost specimens in former times; they were simply imported from the wild. This has become increasingly impractical in recent years for a number of reasons. In the first place, some animals have become exceedingly rare due to human destruction of their habitats. Even if zoos were willing to pay exorbitant sums to receive such animals, they would be difficult to find. Secondly, and most fortunately, more international laws have been created that regulate wild animal trade, thus providing strong protection for threatened species. Thirdly, good zoos feel a moral responsibility to keep the importation of all animals, threatened or otherwise, to an absolute minimum.
Therefore, zoos now strive to build up and maintain self-sustaining captive populations that do not require the addition of new specimens from the wild. Achievement of this requires efficient management an several levels. The most basic is that individual animals must be guaranteed a long life of quality. On the second level, breeding pairs or groups must be managed so that reproduction is sufficient to assure the continued viability of future generations. On a world wide scale, the total zoo population of each species must be managed.
It is clear that the first two levels relate to quantity, or to population sizes of the animal species in the zoo. It is only possible to maintain adequate numbers if animals do not die prematurely and reproduction is successful. Much attention must consequently be given to important management factors such as housing, feeding, medical care, and the establishment of suitable breeding pairs or groups of animals. Zoo personnel draw an the knowledge and experience accumulated through more than 150 years of zoo history to approach management problems. Zoos continue to collect useful data through new experiences as well as research in all areas of biology and veterinary science. In this age of serious animal management, communication between zoos to disseminate useful information is increasingly important. Gone are the days when zoos could afford to be secretive and competitive; cooperation is now an essential management tool.
The third level of management deals not with quantity, but rather with quality of zoo animal populations. Preservation of a threatened species is not only a matter of having sufficient numbers of individuals, but also of preserving the original characteristics found in wild populations. This is not easily accomplished, and now zoos are working together to meet this objective through formation of cooperatioe breeding programmes.
EEP: European breeding programmes
For zoo visitors to have the opportunity to See how wild animals look, live, and behave, zoos must ensure that truly wild animals, with all of their natural characteristics, are presented. Zoo animals are vulnerable to three very serious breeding problems inherent to small, artificial populations: inbreeding, loss of genetic variability, and unnatural selection. These Problems can easily result in loss of original wild traits, and in the expression of heritable abnormalities. If what was once a pure, wild population of animals deteriorates through generations of uncontrolled breeding into inferior or partially domesticated stock, then the animals are no longer suitable for any conservation effort, and the zoos have failed to perform an important educational task.
Fortunately, the effects of breeding small populations of wild animals in zoos over periods of many generations have been well studied in the past ten years, by researchers both within and external to the zoo field. Based an these studies and genetic theory, guidelines for breeding such small populations have been developed. Following such guidelines should sharply reduce possibilities of above mentioned breeding problems and concurrently should maximize the number of generations in which the original wild traits can be maintained. Guidelines for Small populations follow some basic principals: for example, it is highly desirable to begin with as many "founders" for the population as possible, preferably at least several tens of animals. The number of individuals within the population should be rapidly increased, and all individuals from the founder population should have "equal genetic representation" while inbreeding of closely related individuals should be avoided. lt is important that the number of males and females in the breeding population remain balanced.
The application of these guidelines, and many others tailored to specific populations, results in strictly controlled breeding programmes in which nothing is left to chance. Only in this manner can healthy and truly wild populations be maintained over a period of one or two hundred years. Such strict control is entirely dependent an cooperation among zoos that hold individuals of the species, as Single zoos generally do not have the facilities to maintain a population of adequate size independently.
It is in fact, usually the case within Europe that not even all of the zoos within one country have sufficient numbers of individuals of a species to manage it well. Thus, international cooperation in breeding programmes is necessary, and to this end the EEP-organisation was formed in 1985. The EEP, an abbreviation of "European Endangered Species Programme", is a breeding programme organisation of European zoos directed towards the conservation of wild animal species in zoos. Programmes for seventeen species, such as the red Panda, the European otter, and the Congo peacock, were undertaken by the organisation in 1985. The number of species targeted has steadily increased since then, and assuming the trend continues, programmes for several hundred species will be underway by the year 2000. The EEP programmes are directed towards species threatened in nature, as these are most critically in need of such efforts. lt is important to protect as many of these species as possible in zoos, where they can fulfil their important roles as ambassadors of nature conservation.
Within the EEP framework, a "species coordinator" is appointed for each species programme; usually this individual is an employee in one of the participating zoos, and is an expert an the species in question. The coor dinator compiles a studbook that includes a listing of all individuals of that species held by European zoos, together with all the relevant information about each individual, including all data concerning kin and offspring. This information is then analysed: family relationships and past breedings are assessed, Sex ratios determined, and degrees of inbreeding are calculated. The representation of different lines stemming from the "founder population" are scrutinized; some lines may be over-represented while others are underrepresented. Numerous such calculations are made, and the entire procedure can become quite complicated, particularly if the species in question has been breeding in zoos for many generations. Fortunately, the species coordinator's task is made easier through the use of specialized computer Software that is designed to assist in data input and processing.
The interpretation of the analyses is far from simple, but the species coordinator is aided in this endeavour by a "species commission", made up of five to ten people representing zoos and other institutions from different European countries that have experience in breeding the species in question. Based an the analyses, the species coordinator and commission recommend strategies for breeding the species in the upcoming year, determining which animals should breed, and in what combination. Some logistics to be worked out include: which animals must be exchanged between zoos so that they can reproduce but will avoid inbreeding? In which genetic lines should breeding be discouraged or stimulated? Is it necessary to rapidly increase the population size at this time? Are there eurrently sufficient facilities in the zoos holding specimens, or should some more zoos be encouraged to participate in this species' programme? Are the housing conditions adequate, or do they need to be improved in order to stimulate breeding? These and a number of other questions need to be answered, and breeding strategies reviewed and revised an an annual basis, according to the previous year's events.
The species coordinators have a two-day meeting once a year, in which they come together to discuss the EEPs, and to acquaint themselves with the most recent developments in the area of breeding programmes. The meetings provide an opportunity to resolve practical and theoretical problems, and to set organisational policy and recommendations. The species coordinators receive support and guidance through the "EEP Coordination Commission", a group consisting of leading zoo representatives from European countries. This commission is the general policy making organ of the EEP-organisation, and additionally selects which species will be recommended for inclusion into EEP programmes. The "EEP Executive Office" in Amsterdam is responsible for the daily business an behalf of the Commission.
The largest problem encountered in the functioning of the EEP Organisation is undoubtedly the actual execution of breeding management recommendations: it is often difficult to develop policies applicable to an entire group of zoos (varying from 10 to well over 50 depending an the species programme) when these are spread throughout several countries with different languages and laws, and with dissimilar political and economic backgrounds. Just the incongruencies in laws can sometimes make exchange of specimens for breeding purposes by two closely situated zoos a formidable task if a border happens to lie between them. Yet successes have been achieved: the growth of the EEP-organisation has been considerable since its initiation in 1985. Now more than 200 zoos from 25 European countries are involved in breeding programmes, while the EEP is strongly supported by the various national zoo federations and by the European Community Association of Zoos and Aquaria (ECAZA). Currently, preparations are being made to found a pan-European zoo association that, among other tasks, will be responsible for EEP affairs.
The EEP in the world
The European EEP breeding programme organisation does not stand alone. It is one of the worldwide assembly of such regional breeding programmes for threatened species in zoos. The Species Survival Plan (SSP) is the North American counterpart. Australian, Japanese and Indian zoos all have similar programmes, and zoos in other regions will soon follow these examples. Combined, there are now many hundred zoos throughout the world involved in the regional breeding programmes.
Although these diverse programmes in principal operate independently, there is an underlying worldwide coordination in the form of the "Captive Breeding Specialist Group" (CBSG). This important organisation is one of the many "Specialist Groups" of the "Species Survival Commission", a section of the International Nature Conservation Organisation (IUCN). Most of the "Specialist Groups" are directed towards a particular taxonomic group of plants or animals; for example specialist groups have been formed for bears, antelope, and the aggregate of birds consisting of storks, ibises and spoonbills. Specialist group members are leading experts of the species addressed, and are often involved in conservation and/or study of these in their native habitats. In contrast the "Captive Breeding Specialist Group", consisting of more than 150 specialists, concerns itself with all aspects of successful propagation of threatened species outside of their natural environments; thus zoos play an important role in this groups' activities. The CBSG determines which threatened species Captive breeding programmes are necessary for, and fine-tunes the united efforts of the various regional programmes. In this, the CBSG is strongly supported by the global zoo organisation IUDZG (International Union of Zoological Gardens and Aquaria).
There is a very important connection between zoos and preservation of threatened species that has led to the involvement of IUCN in captive breeding programmes; this being that a number of species have become dependent upon zoos for their very survival. Some species that illustrate this point particularly well are Pere David's deer, Przewalski's horse, and Arabian oryx; all became extinct in the wild but are flourishing in captivity. A number of other species are not yet entirely gone from their natural habitats, but are in such jeopardy that their continuation is highly uncertain. Breeding programmes undertaken by zoos, in which the animals enjoy protection from the threats facing their wild counterparts, may be crucial to these species' survival. It is particularly important in such Gases to abide by breeding programme guidelines that will help maintain the wild traits in the captive populations.
Slowly, nature conservation organisations have begun to look more frequently to zoos for aid in saving species that would otherwise be lost. In some Gases zoos have undertaken "rescue operations" at the urging of conservationists, wherein the few remaining individuals of a critically threatened species were caught and a captive breeding programme initiated, thus keeping the species from the eternity of extinction.
Back to nature?
Populations of animals should be able to remain in zoos for many generations with their wild traits entirely intact, provided that breeding is strictly controlled. Theoretically they should be able to return to their natural habitats, adjusting to the brutal selective pressures wrought by nature, after generations of relative security and protection in captivity. Such animals could be welcome additions to populations low in numbers ("restocking"), or Gould be used to establish entirely new groups in the wild ("reintroduction"). This would indeed be the consummate contribution that the zoo world could make to nature conservation of such species. Ensuring the success of a project involving the translocation of zoo animals into the wild for reintroduction or restocking purposes is not as easy as it may seem. In practice all sorts of unexpected problems may be encoun tered. lt must be assured that the animals have indeed retained enough of their natural behaviours to enable them to survive in the wild. Will the falcon still be able to capture its prey? Or will the primate still know which plants are poisonous and which are edible? Another important consideration is whether or not the factors that led to the species' decline are still operating - animals should not be reintroduced until these factors no longer pose a threat. In some Gases it may be difficult to find any site suitable for reintroduction efforts, as the species' habitat has largely, or even completely, disappeared. Animals used for restocking must be disease free, and enhance the health of the remnant wild population.
It is clear that reintroduction and restocking efforts involving zoo animals must proceed with great care. A well elaborated plan must be developed by all parties involved, such as the national and local government, nature conservation groups and the local population within the country where the reintroduction is to be attempted. The animals should be extensively prepared for life in the wild prior to their release, and once released they should be closely monitored and protected for many years. Presently, reintroduction and restocking projects have been attempted for over fifty species, ranging from the Arabian oryx, Przewalski's horse and golden lion tamarin, to Guam rails, Mauritius pink pigeons, and even toads. The results have been variable, but the best organised programmes have demonstrated that the numerous practical problems can be overcome and success can be achieved.
Thus, reintroduction and restocking do offer a realistic chance of survival for at least a number of species. However, it is an infinitesimal number. Thirty thousand species of plants and animals are now threatened with extinction, and some authorities predict that more than one million species will disappear from the earth during the coming century. With all the attention zoos can now give to threatened species, they can properly main-tain only several hundred species. If this effort was maximized, perhaps a thousand species could be targeted. A futile battle, thus? We don't think so!
This brings us back to the most important function that zoos have in conservation, that of carrying the conservation message. The example set by efforts with these few species is far more important than the actual number of species that are worked with. Just as the presence of threatened animals in the zoo can be useful in bringing home the idea of conservation generally, reintroduction and restocking efforts can focus attention an conservation and protection of the last natural areas in which these animals can be suitably released. The focus is then not only an the reintroduced species, but also an the entire habitat, with the hundreds or thousands of other species that occur there. This will have a far reaching impact, as people in both the country in which the reintroduction is being made and the countries providing the zoo animals are able to see that no exertions are too great to save the precious pieces of nature.