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The Control of Zoo Populations with Special Reference to Primates

Published online by Cambridge University Press:  11 January 2023

A R Glatston*
Rotterdam Zoo, Postbus 532, 3000 AM Rotterdam, The Netherlands


Modern zoos are increasingly successful in maintaining and breeding exotic species. Many of the animals bred in captivity cannot be housed in their natal zoo nor in other recognized zoos in the region. These ‘surplus ‘ animals create a problem as zoos only have limited space at their disposal. The options open in this situation are to avoid the problem by preventing the animals from breeding (sterilization or contraception) or to dispose of the surplus animals (euthanasia; or transfer either to institutions not recognized by any national zoo federation or to a zoo outside the region, possibly using the services of an animal dealer). The pros and cons of all these options are evaluated in terms of practicality, welfare and ethics. In many cases, the judicious use of a combination of contraception and euthanasia would seem the most acceptable choice from an animal welfare point of view. Nevertheless, it is believed that considerably more research is needed into the methods and welfare aspects of contraception and sterilization.

Research Article
© 1998 Universities Federation for Animal Welfare

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