Conserving Golden Lion Tamarin The Problem The Golden Lion Tamarin (Leontopithecus rosalia) also known as Golden Marmoset, is a small New World monkey of the family Callitrichidae. Native to the Atlantic coastal forests of Brazil, the Golden Lion Tamarin is an endangered species with an estimated wild population of "more than 1,000 individuals" and a captive population maintained at approximately 490 individuals.
Most of the wild population is confined to the Poco das Antas Biological Reserve, a protected area of swampy forests in the state of Rio de Janeiro.It is an important bastion of the Golden Lion Tamarin, as only 2% of forests in the monkey's original range remains. Furthermore, its existing habitat has been broken up by logging and agriculture; this has led to isolated populations and inbreeding, a combination likely to result in extinction. WWF is currently working to increase the protected area of forest available to these animals, and zoos are reintroducing captive-bred tamarins to the wild.Deforestation in the state of Rio de Janeiro began in the 16th Century, with successive cycles of development supporting sugar cane plantations, coffee plantations, and in the last century particularly cattle breeding, besides persistent logging, charcoal production, and clearing for urbanization. The state is one of the most populous regions of Brazil, and today L.
rosalia is limited to some few and isolated forest patches. Approximately 20% of the original range of L. rosalia is still forested, but 60% of this total is comprised of patches of 1,000 ha or less, 96% of which are less than 100 ha.The average size of the forest patches is 35 ha: smaller than the home range of a single lion tamarin group (Kierulff and Procopio de Oliveira 1996). Fires, set by cattle farmers adjacent to the remaining forest patches in the region, are a constant threat. http://www.
iucnredlist. org/apps/redlist/details/11506/0 A Possible Solution Captive breeding There are now breeding populations of golden lion tamarins in zoos around the world.The Species Survival Plan (SSP) is coordinated by the National Zoological Park in Washington, D. C. Over 50 golden lion tamarins are born each year in captivity. The process involves breeding animals in human controlled environments with restricted settings, such as wildlife preserves, zoos and other conservation facilities; sometimes the process is construed to include release of individual organisms to the wild, when there is sufficient natural habitat to support new individuals or when the threat to the species in the wild is lessened.
Another goal of captive breeding programs is to maintain an appropriate level of genetic diversity, which can allow the population be adaptable to conditions in the environment after release. The primary objective of captive breeding programs is to maintain demographically stable populations of sufficient size to preserve some high level of gene diversity (typically 90%) over a long time period (such as 100 years). The rationale for preserving high levels of gene diversity is twofold: to preserve the evolutionary potential of the population and to minimize the deleterious effects of inbreeding, which can be substantial .Achieving these objectives also serves to meet many of the other functions required of zoo populations (exhibitory, conservation education, research, and public outreach) although at times there obviously can be conflicts among these various roles.
Establishing and managing a captive population can be typically conceptualized as occurring in 3 phases: the founding, growth, and maintenance phases (Figure 1). Population growth may be slow during the founding phase as husbandry techniques are developed and refined.Once these become established, the population will often grow rapidly with an accompanied increased dispersal of the population among many zoos. The population is encouraged to continue to grow until it reaches the desired (target) size.
The target size will enable the population to maintain a high level of genetic diversity (e. g. , 90%) over a 100-year period and is a function of the number of founders, potential growth rate of the population during the growth phase, how well the population is genetically managed, and the generation. Thus the target size is calculated specifically for each population using computer models.
In golden lion tamarins the target size of the captive population is estimated to be about 480 individuals. Reproduction is slowed during the maintenance phase to keep the population at its target size. Genetic management (that is, the selection of breeding mates based on pedigree analysis) occurs during all 3 phases, although during the earlier phases there may be a higher priority placed on successful reproduction than on genetic issues (that is, who should breed with whom). The development of the captive population for the golden lion tamarin followed such a progression (Figure 2). To prevent inbreeding every zoo has a studbook .
A stud book is a breed registry of animals within a specific breed whose parents are known. The studbook/breeding program is about managing species in captivity. Several zoos around the world co-operate in the breeding of the golden lion tamarin, moving individuals among the various zoos to prevent inbreeding. Over 50 tamarins a year are born in captivity. Hopefully, it will be possible to introduce many of these to the wild in future years.
Implications Ethical Captive breeding is seen as an interference with the nature because it eliminates natural selection; this means individuals that are not able to survive in the wild will survive.Many People think it is cruel to keep animals in captivity because they are not free as in the wild and are often not comfortable with their new surroundings. Animals bred in captivity can quickly become less fit for survival in the wild, research suggests. “US scientists found steelhead trout reared in hatcheries were much less good at reproducing than wild fish. ” An evidence shows that animals kept in captivity behaves differently than those in the wild.
“The lions were so unused to the world outside their cages that they were frightened of grass and too nervous to drink water from pools in their enclosure. If this is the case the outcome of the reintroduction may not result as a great success. Captive breeding in some part of the world is poor. The handling, husbandry and keeping conditions are frequently poor and nutritional deficiencies and injuries are common. Some breeding facilities use the cubs to draw paying volunteers. Others claim that cubs were orphaned and for an amount of money you can adopt a cub.
Reintroduction may cause some problems for surviving wild populations and ecosystem if not planned properly. It may affect the local ecosystem and may as well threaten the local population.Animals in captivity are in close contact with other animals and exposed to diseases against which they are not immune. They may be infected and after reintroduction transmit diseases to the wild population.
Economical Captive breeding is a long term program which requires large amount of money from local and government funds for running the zoo effectively and appropriately. Big sum of money should be invested in building artificial habitats for the Tamarin’s and employing Numbers of skill full zoo-keepers to look after the tamarins.It has not always proven to be 100 % successful, if the result is ineffective it will just be a waste of time and money. The money could have been spent on other big projects. Most less developed countries show worse ecological environment, but they do not have finance for captive breeding. In addition, the personnel are small numbers who earn a small income, in spite of lots of effort.
Therefore, wealthier governments should be concerned about captive breeding in the global view. Benefits and Risks BenefitsThe main benefit of captive breeding is that it helps to restore endangered species by increasing its number, moreover it allows breeders to maximise genetic diversity. It has proven to be very useful and successful method. Another advantage of keeping the tamarins in captivity is that research in zoos will increase knowledge about the behaviour and physiology of the Tamarins which can contribute to conservation efforts in the wild. Captive breeding stops extinction from occurring. Zoos can also carry out different kinds of research which is not possible in the wild, for example: reproductive and nutritional studies.
Risk Although captive breeding has shown to be fairly successful it also has some drawbacks. If all Tamarin individuals are offspring of the same parents Tamarin, then the population is likely to have low genetic diversity because of the effects of inbreeding (breeding between closely related individuals). This can also lead to a phenomenon known as inbreeding depression, a detrimental effect on offspring that can result from mating between close relatives. Inbreeding depression is due to an accumulation of deleterious recessive alleles, which can become expressed in a high frequency in inbred populations.
Inbreeding depression can be manifested as lowered fecundity; smaller numbers of offspring produced, and decreased survival after birth. If a highly inbred population was reintroduced into the wild, its chances of survival and reproduction are likely to be relatively low. In essence, genetic diversity helps to ensure that a released population will be able to survive and grow, despite natural selection against some of its individuals. [25] Because of the limited gene pool in a too-small group, the percentage of detrimental traits bred in the wild population is high.
The captive breeding and reintroduction projects sponsored by the Golden Lion Tamarin Conservation Program have begun to restore genetic diversity in the golden lion Tamarin population. It is unknown if zoo-born golden lion tamarins can be taught to survive in their native forests. Reintroduction Reintroduction is the deliberate release of species into the wild, from captivity or relocated from other areas where the species survives. It usually involves species that are endangered or extinct in the wild An intensive reintroduction program has allowed more than 70 tamarins to be released into Brazil's protected area.Mortality is high; however, up to 70 percent die in the first year after release when zoo-born tamarins are set free in the forest they become disoriented and helpless and do not know how to feed themselves.
Efforts are being made to release golden lion tamarins into "half-way houses," large caged-in areas of the rain forest, where the tamarins can learn to navigate their multidimensional habitat while being protected from predators and supplied with food supplements. Since 1984, 147 tamarins have been released into the wild. It is hoped by 2025 there may be 2000 wild golden lion tamarins. Bristol Zoo Gardens are an mportant part of the captive breeding programme for this species.
Since the ultimate aim is to re-introduce animals back into a native habitat, maintenance of the original genetic diversity is crucial to the eventual survival of those individuals in the wild. Also, captive breeding over several generations may select for characteristics such as docility, which are not advantageous in the wild. Habitat Protection and Community Education Most of the area where tamarins occur in the wild was declared a preserve in 1980, but it is poorly protected. CITES prohibits trade, and local laws prohibit killing of the species.However, a recent study showed that the Brazilian community-education program on the endangered golden lion Tamarin was failing to reach local farmers. Although the Tamarin is widely used as a symbol and focal point to encourage conservation of endangered coastal rain forest, only 19 percent of farmers approached knew the Tamarin was endangered.
Mature forest now covers less than 10 per cent of the reserve. Habitat improvement is essential if the wild and captive-bred tamarins are to survive. Education is important too and a programme has been set up to help the local people to understand the importance of conserving the remaining forest.
