Controversial Population Management Methods Within Zoos
Zoos around the world are faced with two different options to keep their animal populations under control while preserving genetic diversity within their establishment. Both methods have proven quite controversial with one including euthanasia and the other being birth control. The New York Times recently shed some light on the pitfalls of both sides of the coin.
Both strategies have their downfalls of course but death by lethal injection sure doesn’t seem fair. Members of the Copenhagen zoo in Europe feel that allowing the adult animals to experience the natural cycle of procreation and nurturing as they would experience in the wild is important. In short, they would rather kill innocent young animals than deny the parents of this instinctive and natural behavior.
Bengt Holst, the director of conservation for the Copenhagen Zoo was quoted in the New York Times saying:
“We’d rather they have as natural behavior as possible. We have already taken away their predatory and antipredatory behaviors. If we take away their parenting behavior, they have not much left.”
The members of the zoo generally allow the animal parent to raise their young until they are adolescents and then euthanize them at a time that they would naturally separate from their mothers in the wild. They do this when any animals that are born do not fit into their breeding plans and as a population management tool in order to maintain genetic diversity among the animals that reside there. The Copenhagen zoo admitted to humanely euthanizing two leopard cubs at the age of 2 years old just last spring. Leopards are on the International Union for Conservation List under the ‘near threatened’ status. The Copenhagen zoo typically puts down twenty to thirty exotic animals with some species including hippos, gazelles, and chimps.
The justification for lethally injecting perfectly healthy young leopard cubs includes a strategy that mimics what would happen in the wild as 80% of feline cubs die from predators, starvation, or injuries. Under the American Zoo Association regulations, euthanasia is completely legal but is mostly set aside for sick and elderly animals.
A more humane approach to regulating species populations within zoos is to use contraception or birth control methods. While the topic of birth control in our human health care is a hot button issue at present time, it is also taboo in the animal world. Currently chimps in zoos located in The United States take birth control, giraffes are dealt hormones right in their food, and bears are given hormones that release slowly into their bodies from their legs. Birth control has side effects in humans and the same goes for animals. They can develop uterine diseases and tumors and may struggle to start their reproduction organs back up once they discontinue use of the “pill”.
Animal rights activists have been on the case of a zoo in Germany that euthanized three male cubs because they discovered the male parent was a hybrid of two tiger subspecies. The director along with three employees were prosecuted for violating euthanasia law.
The public feels strongly that there has to be a better way to control populations within zoos. Both methods have their downfalls but hopefully the United States does not ever accept the killing of innocent baby animals just because there is no room for them in their facilities.
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