We are the EAZA Reproductive Management Group, a group formed to gather knowledge on the use of contraception in ex situ animals within Europe.
We are an active part of the European zoo and aquarium community, producing contraceptive guidelines for institutions, breeding programme coordinators, and Best Practice Guidelines.
What is animal contraception?
Prior to the introduction of contraception, zoos had four options when it came to managing populations: separate males and females, struggle to care for animals exceeding available resources, transfer animals to new institutions, or in some cases, cull unwanted young. The advancements of contraception now provide another tool for the management of captive populations as well as a baseline for managing free-living wildlife.
Contraception allows animal managers to maintain sustainable population numbers while minimizing inbreeding within family groups. They can be applied therapeutically, preventing certain behaviours such as excessive egg laying or feather plucking in birds. In primates, contraception can also be used to mediate undesirable sexual behaviours and to manage escalated aggression in large social groups.
Animal contraception is not only used in zoos, but has also been applied in animals in reserves and in the wild. For exmaple in managing aggression in bull elephants going through musth, or even controlling the population size of New York City sewer rats!
Which contraceptive is right?
Choosing the correct contraceptive for the species and situation is not a simple case of ‘one size fits all’ as, given the different physiology and life histories of different animals, contraceptives can have remarkably different effects. A prime example of this is the use of progestin based contraceptives; although frequently used in ungulates and primates, use in canids has been associated with uterine pathology and infection as well as uterine and mammary cancer in felids.
Although many methods of contraception are available, providing safe and effective contraception for species with very different reproductive physiologies can be a major challenge. Contraceptive options available to zoos are usually not specifically designed for use in exotic wildlife.
Wildlife contraception is still very much an emerging field, and while knowledge on contraceptive use is extensive, it is patchy in distribution within the global zoo community. In an effort to centralise contraceptive information, the AZA Reproductive Management Center (RMC) and the EAZA Reproductive Management Group (EAZA RMG, formerly EGZAC) share a database detailing the efficacy of different contraceptive methods.
A holistic approach to animal contraception
We would strongly like to encourage any institutions that are planning on using contraception on their animals to supplement any contraceptive bouts with behavioural, hormonal and health monitoring. If you would like any more information on any of these, please do not hesitate to contact us as contraception@chesterzoo.org.