Species management

In nature, three processes regulate populations: reproduction, migration, and death.

Reproduction: Causes the population to grow.

Migration: Mixes the population. Young animals migrate to other areas upon reaching adulthood, if the species' social structure dictates it. 

Death: Causes the population to decline. Animals starve or die of thirst, or they fall victim to disease, epidemics, or predators. Predators typically prey on young, sick, weak, or old animals.

These processes don't happen naturally at the zoo. We have to actively initiate and guide them.

Reproduction

There are three reasons why it is important for animals to be able to reproduce without restriction:

• Reproduction is a basic need for animals. In social animals, raising offspring is also an important group task that the animals must learn. This is only possible if there are actually offspring.

• If there are too few offspring, populations become overaged. In the long term, aging populations can no longer grow on their own and ensure their continued existence.

• Contraceptives can lead to permanent sterility and/or behavioral changes in female animals.

Unrestricted reproduction results in the growth of the animal population. That is why two additional processes are necessary: migration and death.

Migration

Zoos simulate migration by exchanging animals with one another. However, space is limited at zoological institutions. There isn't a suitable destination for every animal.

That is why a third process is also necessary: death.

Death

The zoo will not euthanize an animal until after a thorough evaluation.

The decision to kill is made when ...

• the animal can no longer be used as part of the coordinated conservation breeding program for the continued survival of the zoo population;

• at the same time, there is no suitable placement available that meets the animal’s needs.

Euthanasia is performed in a painless and stress-free manner in accordance with the provisions of the Swiss Animal Welfare Ordinance. Where possible, we use the euthanized animals as feed at the zoo, or, if there is interest, we donate them to research.

In terms of its impact on the population, the killing of animals at the zoo is equivalent to the natural mortality rate of animals in the wild.

Changes in the Zoo's Animal Population

In the overview below, we provide periodic updates on changes in the animal population at our zoo—that is, regarding reproduction (births/hatchings), migration (arrivals and transfers), and deaths.