Chimpanzees in Japan

In Japan, there are 352 chimpanzees (148 male, 204 female: December 2005 Domestic Stud Book records) in 56 institutions. Among these individuals, 247 individuals reside in zoos, 103 individuals in research institutions and 2 individuals in other institutions. Unlike chimpanzees in Western countries, most of chimpanzees in Japan reside in zoos. As of now, there are no or almost no privately owned individuals as pets nor for entertainment reasons but no chimpanzee sanctuary exists for their care and welfare.

Number of individuals residing in institutions
Only 5% of 56 institutions keep more than 16 chimpanzees, and even with institutions that keep more than 11 chimpanzees, this accounts for only 10%. 33% of 57 institutions keep 5-10 chimpanzees, 39% keep 2-4 and 18% keep only one chimpanzee.

Moreover, regardless of the number of individuals that reside in an institution, a chimpanzee may not be kept with other chimpanzees in a group but kept in individual cages. There also exist institutions that do not keep chimpanzees as a group at all.
Comparing to a fact that a wild chimpanzee group may contain 20-100 individuals, it is unquestionable that chimpanzees in Japan reside in a environment that is very different from how it is supposed to be.

As breeding programs progress, the number of chimpanzee in Japan is reaching the limit of current holding capacity conditions. Some institutions are limiting the breeding program itself. However, here are the problems that arise.

Breeding Program

In 1988, for the purpose of conserving rare animals, the Japanese Association of Zoos and Aquariums(JAZA) established the Species Survival Committee (SSCJ) as the support organization of the Board of Directors. Chimpanzees are listed as rare animals in captivity in Japan, and are considered for propagation plans including breeding loans with institutions other than JAZA under the coordination of the Stud Book keeper. Annual surveys are conducted for this document.

Breeding program with consideration for "subspecies" level identification

Since it is hard to distinguish chimpanzee subspecies morphologically, the care for chimpanzee under captivity had not giving much attention to the matter of hybridyzation until maternal molecular phylogenetic analysis using mitochondrial DNA became available. Nationwide subspecies identification was conducted in 2001, and the results showed that one third of the chimpanzees in Japan are hybrids (about 60% are Pan troglodytes verus and a few are Pt schweinfurthii and Pt troglodytes troglodytes).

In order to preserve chimpanzees at the subspecies level, it is necessary to put efforts into producing no more hybrids. To put this plan into practice, each institution (that keeps chimpanzees under captivity) needs to have a care management system that secures birth control (use of pill, inplant, pipecut etc,). Controlled breeding is a must, yet it is important to establish QOL (Quality Of Life) to provide appropriate husbandry for the existing hybrid chimpanzees.

From "Individual" or "Paired" captive environment to "Group" living

In classical zoos, since cages were lined up next to each other, chimpanzees were often kept as a male female pair. After the discovery of social life of wild chimpanzees that live in groups, zoos that could afford the space, changed their exhibit design so that captive chimpanzees could also live as groups. However, for various reasons, many zoos are unable to provide such environments.

Breeding program considering "Genetic diversity"

Since wild chimpanzees live in groups and have a social life, when kept as a pair in zoos, it is understandable that breeding doesn't occur easily. Naturally, at zoos, more offspring that are bred among chimpanzees who are kept in groups exist now. Furthermore, there are more offspring of actively reproducing individuals. This has resulted in the current skewed gene pool. If this continues, there will be many individuals that are close relatives to each other.

To conserve "genetic diversity" of captive chimpanzees in Japan, it is important to avoid inbreeding and make efforts to balance the reproductive output and genetic representation of all individuals by providing an environment that allows for this.
Easy to say, hard to do. All sorts of difficulties will emerge when trying to provide an environment that enables never bred individuals to breed. For example, transferring chimpanzees may be problematic due to the number or the size of the holding area, or there may be social skill problems that disable breeding such as incompetence in pairing or difficulty being introduced to a group. Besides, in the case of hand-reared individuals, since he/she has never had a chance to learn how to breed or rearing infants (which is usually learned when brought up in a social group), he/she may not be able to do so appropriately.

It is the law of nature that founding chimpanzees of most colonies are getting old, which means that their breeding ability is declining. (Due to CITES in 1980, importing chimpanzees has become difficult and is no longer happening. There is no possibility to import wild chimpanzees to Japan in the future) Founding chimpanzees who possess precious genes that can help to maintain genetic diversity are getting old without leaving offspring. As an emergent situation, we may need to utilize artificial breeding in the future.

Artificial breeding techniques include artificial insemination, transplantation of fertilized eggs and external fertilization. In Japan, since Kyoto University Primate Research Institute (KUPRI) succeeded in artificial insemination in1982, many zoos have began to practice artificial breeding. Artificial breeding of chimpanzees is now becoming a well-established technique. However, there is a dilemma; artificially bred infants are often abandoned, and are hand-reared which means that herself/himself becomes an adult who may not be able to give or rear a child. So, after artificial breeding succeeds and an infant is born, it is necessary to provide a suitable educational program and environment so that the individual can learn social skills at each level of development. There is also the problem of providing space for newborn. Considering all of the above and the welfare of individuals, even though it is a priority, conserving species by breeding individuals may not be the only solution or may not be enough to solve the problem quick enough.

A gene bank may be the ultimate solution. Isn't it about time that we discuss in detail about preserving sperm and eggs of phylogenetically important individuals for future breeding? Of course this cannot be accomplished by one institution alone, zoos and researchers need to collaborate to conserve a wider variety of genes.

Care with consideration in "environmental enrichment"

Public awareness of evolutionary background, mental ability and society of chimpanzee is growing rapidly. Major zoos do not only keep chimpanzees in groups but also try to provide environment in which chimpanzees can be more active. It is important that caregivers and managers of institutions deepen their understanding of the natural life of wild chimpanzees and apply and practice their knowledge in the care and display of chimpanzees.

Nevertheless, in Japan, there still are many institutions where chimpanzees reside alone or in pairs. (Of course to transform an institution to keep chimpanzees in groups costs a lot.) Even at zoos whose existing exhibits are the classical lined up cages, it is meaningful to think about and apply ideas so that chimpanzees can spend more a lively daily existence.

Network of chimpanzee caregivers

Thanks to the efforts of many people trying to create a Stud Book and to identify individuals at the subspecies level, we are more aware of each individual chimpanzee. Obtaining more information such as the nationwide condition of the captive chimpanzee environment (e.g. number of holding areas, are they kept alone or in pairs, future plans etc.,) will help in dealing with the diverse problems that we may face in the future. Moreover, collecting information on caregiving techniques, it will be helpful in solving problems such as group introduction, infant abandonment and artificial breeding.

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