Working with animals at Copenhagen ZOO

It is the animals’ natural behaviour that makes them so fascinating – and that is what guests come to Copenhagen Zoo to experience and learn about. That is why modern zoos like Copenhagen Zoo focus on encouraging as much natural behaviour as possible, including through enrichment and training. Giving animals opportunities to express the behaviours they would also display in the wild helps support their welfare and quality of life in their enclosures.

We know that we can never recreate conditions exactly as they are in the wild. But we can go a long way by basing our work, like all serious zoos, on science rather than gut feeling or romanticised ideas about how animals think and feel.

Animal enclosures are designed to meet the species-specific behavioural needs of the animals, including giving them the opportunity to get the exercise they need.

Animals do not, for example, have a particular need to “wander”. They move around when there is a reason to do so. Anything else would simply expose them to additional risks. So if we make sure the animals have what they need and are not exposed to danger, there is no reason for them to keep moving around. They must, of course, still be able to move enough to get the necessary exercise.

There is naturally a lower limit to what is acceptable when it comes to enclosure size. But in a modern zoo, we are nowhere near that limit. The quality of an enclosure – in other words, how it is designed – is far more important than its size alone.

It is the design that provides the animals with daily challenges, makes their lives more complex and encourages a wide range of natural behaviours. A smaller enclosure that is well designed can therefore be better than a large enclosure that is poorly designed.

Imagine, for example, a fenced football pitch for a small group of squirrel monkeys. It would give them plenty of space, but very few meaningful challenges. In fact, the monkeys would probably feel highly exposed in such an open area and huddle together in one corner. A smaller enclosure with trees and bushes, where they can hide and move away from one another, would do a much better job of meeting their behavioural needs and giving them a sense of security.

Some guests also ask whether we buy and sell animals. The answer is no. Serious zoos do not buy and sell animals; instead, they exchange animals with one another, with transport being the only associated cost.

Animals are moved according to what is best for the population, not for financial reasons. If we are to maintain healthy populations far into the future, animals need to be able to move freely between zoos so that the best possible genetic composition can be maintained.

For the same reason, European breeding programmes were established in 1985. Within these programmes, decisions about moving animals are not made by individual zoos, but by species coordinators. Using studbooks for each species, they work to ensure that the European population has the best possible genetic composition. This is essential for maintaining healthy populations in the long term.

As part of this work, animals need to be moved between zoos on an ongoing basis. Otherwise, breeding problems would quickly arise. In the wild, animals may disperse to find a mate or join a new group. In zoos, the species coordinator organises these movements, while the individual zoos are responsible for transporting the animals.

Typically, an individual animal will only be moved once or twice during its lifetime. When this happens, the transport follows detailed guidelines established by the International Air Transport Association (IATA).

Both when animals are selected for transfer and during the transport itself, great care is taken to meet their behavioural and physiological needs, including their social needs. Naturally, no one benefits if an animal experiences trauma during transport or is unable to settle into its new enclosure because of stress or similar issues.

Just as animals in the wild are often good at adapting to new conditions as they move from place to place, animals in zoos are generally good at adapting too. They quickly develop what can be described as a “normal picture” of their surroundings, and as long as that picture does not change significantly, they feel secure.

This can be seen clearly in behavioural studies. But if that normal picture is disrupted – for example, if someone crosses a barrier into an animal’s space – the animal may become frightened and move away. And that makes sense. Take antelopes on the African savannah. If they were constantly afraid simply because they could smell lions, they would be under almost continuous stress, as they may spend much of their time within range of a pride. Instead, they become accustomed to what is normal in their surroundings – including the scent of lions and even the sight of them at a certain distance.

But if the lions change their behaviour and begin to stalk rather than move around normally, the antelopes react and flee. The same principle applies in a zoo. As long as visitors remain on their side of the barrier, the animals generally regard them as part of their everyday surroundings.

It is true that some animals can occasionally display stereotypic behaviour. When that happens, it is important to work specifically with those animals to identify and address the underlying cause. One example of stereotypic behaviour is an animal repeatedly pacing back and forth along the same route.

Stereotypic behaviour can indicate that something in the animal’s environment is not meeting its needs. This could relate to the design of the enclosure or the social composition of the group.

In other words, stereotypic behaviour can be an important signal that something needs to change. In the past, attempts were sometimes made to stop stereotypic behaviour simply by preventing the animal from performing the repeated movement. But that only treats the symptom. With what we know today, the right approach is to identify the cause and address the underlying problem rather than simply trying to stop the behaviour itself.

Few zoos can say that stereotypic behaviour never occurs among their animals, and Copenhagen Zoo is no exception. The difference today is that when it does occur, we work systematically to improve the situation. It can take time, but in most cases it is possible to make meaningful improvements. Overall, stereotypic behaviour is now relatively uncommon in scientifically managed zoos, although it has not disappeared entirely.

The behaviour itself is not necessarily the main problem. In some cases, stereotypic behaviour may help an animal cope with a situation it finds difficult. For us, however, it remains an important sign that something may be wrong and needs to be taken seriously.

That is why we have a professional team of zookeepers, vets and zoologists caring for the animals, and why we devote significant resources to what is known in zoo terminology as enrichment. In simple terms, enrichment means providing the animals with varied challenges and opportunities in their daily lives, encouraging natural behaviour and helping create an environment that meets their behavioural needs.

It is true that some of our breeding programmes involve species that are not currently threatened in the wild. But threatened species are not the only animals worth learning about, caring for and preserving for the future.

That is why we have breeding programmes for both threatened and non-threatened species – to help ensure that healthy populations still exist 100 years from now and beyond. If we wait until a species is already severely threatened in the wild before establishing a breeding programme, it may simply be too late.

Zoos work systematically to help conserve the diversity of the natural world, while recognising that it is not possible to save everything. But zoos can make an important contribution, and we have a responsibility to do so by continuously managing and improving the health of our animal populations.

Breeding is therefore not about “entertainment”. It is about creating fascination, inspiring people and encouraging a sense of responsibility for nature – a responsibility that can help ensure future generations are also able to experience its extraordinary diversity.

The alternative to scientifically managed zoos is a future in which coming generations may no longer experience the remarkable diversity of the animal world – and therefore have less opportunity to form a connection with it. Without a connection to nature, people are less likely to feel responsible for protecting it. And that weakens the very foundation of conservation.

Yes. Running a zoo involves a number of zoological and ethical considerations.

At Copenhagen Zoo, you can experience a wide variety of animals, from butterflies to elephants. The animals thrive, and we place great emphasis on giving them as many opportunities as possible to express their natural behaviour. What most people do not necessarily think about is what lies behind maintaining such a diverse animal population: Where do the animals come from, and how do we maintain healthy populations over time? This is where some of the zoological and ethical considerations come into play.

Almost all animals at Copenhagen Zoo were born in zoos – and that is intentional. Only in very rare cases do animals come directly from the wild, and only as part of an international breeding programme. One example was in 1998, when Copenhagen Zoo brought four young musk oxen from Greenland into the European breeding programme.

Copenhagen Zoo also has a responsibility to keep its animal populations healthy and to continuously renew them, so there will still be healthy animals in the future. We do this, among other things, by allowing the animals to breed and by carefully selecting suitable breeding pairs.

When breeding pairs are selected, the male and female must not be closely related. Breeding between related animals can lead to inbreeding and reduce the viability of the offspring. Animals that are part of international breeding programmes are matched by a species coordinator, who uses detailed knowledge of their ancestry to identify the most suitable pairings. The species coordinator is responsible for ensuring that the overall population remains as healthy and genetically well balanced as possible, so it can be maintained far into the future.

Even with careful planning, animals will occasionally be born that do not fit into the breeding plan. These are sometimes referred to as “surplus animals”. This may be because their genes are already well represented in the population and they therefore should not breed, or because there is not enough space for them within the limited capacity of the zoos participating in the breeding programme.

Why not prevent some animals from breeding so that there are no surplus animals? This can be done by keeping males and females apart, using contraception or sterilising them. At Copenhagen Zoo, however, we do not believe these are good solutions.

Preventing animals from breeding also prevents them from expressing a major part of their natural behaviour: parental behaviour. Depending on the species, animals may spend one, two or several years caring for their young around the clock. Preventing this can therefore significantly reduce their welfare simply to avoid a situation in which offspring may later have to be euthanised.

Hormonal contraception can have side effects and may ultimately result in permanent infertility. Studies have shown that some species can suffer serious liver and kidney damage from hormonal contraception, and that only a small proportion of animals treated with contraceptives for a period of time are able to become pregnant again once treatment stops.

This can have serious consequences, because a population may suddenly contain a large number of animals that are unable to reproduce and produce the number of young needed to maintain it. Research also indicates that social animals that are separated during the breeding season may find it more difficult to reproduce later.

At Copenhagen Zoo, we therefore allow animals to breed at natural intervals. This gives them greater opportunities to express natural behaviour and provides the best possible foundation for international breeding programmes.

If we are unable to move young animals to another zoo at the point when they would naturally leave their parents in the wild, they may be euthanised. In this way, our aim is to ensure that every animal at the zoo has a good life, whether that life is short or long.

Euthanising healthy animals can be ethically justifiable when there is a well-founded reason for doing so. Every day, humans kill millions of animals for food and clothing, and countries around the world regularly manage wild animal populations.

In Denmark, for example, thousands of roe deer are culled, while in many other countries rabbits and wild boar are managed in the same way. These are healthy animals, but they are killed to maintain healthy populations and prevent overpopulation. So euthanising a healthy animal is not necessarily wrong in itself. There must, however, be a well-founded reason. At Copenhagen Zoo, the reason is to help maintain healthy animal populations far into the future.

The animals are also not wasted. They may be used for educational purposes through dissections, while skins and bones are used in teaching schoolchildren or in scientific studies that help us gain as much knowledge as possible about the animals in Copenhagen Zoo’s care. Some animals are also used as food for predators.

Animals should only be released into the wild as part of carefully coordinated programmes designed to re-establish populations or strengthen existing ones. Otherwise, such efforts are likely to fail.

When animals are released, they must be carefully selected for their genetic suitability and their chances of surviving in the wild. They should not simply be animals that are surplus to a zoo population.

A wide range of other conditions must also be in place. The threat that originally caused the species to decline must be under control, there must be enough food available, and there must be sufficient space for the animals to establish the territories they need. These are all factors described in detail by the IUCN, the international organisation for nature conservation.

Nature must never be treated as a dumping ground for unwanted animals.

“Surplus animals” are a natural consequence of successful breeding. This is positive – and necessary if healthy populations are to be maintained far into the future.

In the wild, animals produce far more young than the environment can support, and many die at an early age. In a litter of four lion cubs, for example, on average only one will survive to the age of two. The others may die from starvation, disease or predation. If lions produced only enough cubs to replace those that died of old age, the population would quickly decline.

The same basic principle applies at Copenhagen Zoo. Even though we work closely with other zoos, the amount of available space is limited, so populations must continually be managed according to that capacity. When animals breed successfully, this means that there may occasionally be more animals than can be accommodated within the population.

This brings us back to the question of which animals should be allowed to breed.

Training animals at Copenhagen Zoo is certainly nothing new. Since Copenhagen Zoo’s earliest years, animals have been trained and presented as entertainment for visitors. Guests might once have seen polar bears being walked on a lead by their zookeeper, or chimpanzees painting pictures or taking part in children’s birthday parties. Animals at the zoo are still trained today, but the purpose – and the experience – is now very different.

When guests see zookeepers asking a polar bear to open its mouth or examining a sea lion’s flippers, it might look as though the animals are becoming tame. They are not. The animals participate because there is something in it for them.

The reward does not always have to be food. It may also be attention from the zookeepers or simply the challenge of learning something new. It is particularly important to understand that animals cannot be starved into working or learning. Doing so would damage the trust they have in their keepers, cause frustration and could even lead to aggression.

Animals are not entirely different from us in this respect. Solving tasks, learning and being rewarded can be positive experiences for them too.

Today, the main purpose of training at Copenhagen Zoo is to support high animal welfare and give guests insight into the animals’ natural behaviour and lives at the zoo. Training can benefit both their physical and mental health.

Through training, animals can be encouraged to exercise by moving to different areas of their enclosures in return for a reward. This is also useful when animals need to move between areas during daily cleaning. They learn that moving in and out of an indoor enclosure, for example, when asked by the zookeepers can be worthwhile.

Training can also give animals mentally stimulating challenges or teach them how to interact with enrichment they might not otherwise understand how to use.

One of the most important uses of training at Copenhagen Zoo is veterinary care. Animals can learn to cooperate when blood samples are needed or during routine health checks. They may be trained to step onto scales, have their temperature taken or voluntarily receive treatments such as eye drops or vaccinations. If they need to be transported, they can also learn to enter a transport crate. There is almost no limit to what they can learn.

For a zoo, training is also about safety in everyday animal care – for both animals and people. If staff had to physically restrain a sea lion to administer eye drops, for example, they would be at considerable risk of being bitten, assuming the animal could even be restrained safely.

Sedation is another option, but it also carries risks. Marine mammals, for example, can be particularly vulnerable to respiratory complications during anaesthesia. Sedation would also be a more invasive and potentially stressful experience for the animal. Without training, it would therefore be much harder to provide treatment safely.

Animals that are not accustomed to being touched, handled or temporarily separated from members of their own species may become frightened, stressed or even dangerous in such situations. This is not a good experience for the animals and, in severe cases, stress can affect their health.

That is why we take the time to prepare animals for situations they may encounter at the zoo. Training can make everyday procedures more predictable and help the animals feel more secure. In some cases, a visit from the vet or entering a transport crate may even become a stimulating experience.

Training also strengthens the animals’ trust in the people who care for them and can turn these interactions into an enriching part of their daily lives.

Training can also contribute to research. When a female rhino was pregnant during the winter of 2014/2015, regular blood samples were taken to measure the level of progesterone in her blood.

It was known that progesterone levels would fall sharply shortly before birth, but detailed information about how the levels changed during the final stages of pregnancy was limited. Thanks to the training carried out by the rhino team, researchers were able to gain valuable new knowledge.

Training can also help when changes are made to an animal’s environment, such as introducing new members to a social group. Animals can learn to associate the arrival of new individuals with something positive.

It can also be used to address problematic behaviour, such as aggression or stereotypic behaviour, which may occur when animals feel insecure or have difficulty coping with their surroundings. Training can help reduce the fear or uncertainty behind the behaviour and give the animal an alternative focus.

Finally, training can also benefit guests atthe zoo. Animals have many fascinating abilities that they do not necessarily display while visitors are watching. Through training, animals can be encouraged to demonstrate natural behaviours and abilities on cue. This might, for example, allow guests to see how silently an owl can fly when hunting without alerting its prey.

Animals differ from one another as individuals, and training gives zookeepers a detailed understanding of each animal’s behaviour. This can make it easier to notice subtle changes at an early stage – changes that may indicate illness, pregnancy or problems within a social group. The team can then respond quickly and put a plan in place.

At Copenhagen Zoo, the animals are trained by the zookeepers who care for them every day. They are the people who spend the most time with the animals and know them best. This also means they are often the first to notice changes, such as signs of illness or simply that an animal is having an off day – something that is important to recognise before beginning a training session.

All zookeepers receive training in animal training and are then taught the specific routines used in the departments where they work. It is important that every zookeeper in a department is able to train the animals. That way, there will always be someone on duty who can, for example, ask a polar bear to open its mouth if there is concern about a broken tooth or difficulty eating – rather than having to sedate the animal.

Animals have very different training needs, and zookeepers, vets, curators, enrichment and training coordinators, and educators may all contribute ideas about what kind of training is necessary or beneficial for each species.

For elephants, for example, training is a major part of their daily care. Foot problems can have serious consequences, so their feet need to be checked, trimmed and washed every day. Zookeepers therefore keep a close eye out for things such as stones lodged under the foot, which can cause inflammation, or overgrown nails that may be at risk of cracking.

Before training begins, it is very important to gather as much knowledge about the animals as possible. Copenhagen Zoo is home to many different species that live in different environments and are active at different times of day. Some live in groups, while others are solitary. Some are prey animals and others are predators. Their senses also vary greatly: some animals have excellent eyesight, for example, while others are almost blind.

Alongside knowledge about the species, it is also important to know the history of the individual animal. Some zoo animals live for many years – chimpanzees and tortoises, for example – and may have lived in several different places, such as other zoos, laboratories or private homes, or they may even have come directly from the wild.

Each animal therefore comes with its own history and experiences, including illnesses, births and much more, all of which have helped shape the individual animal. There are many factors to consider before a training programme can be planned.

Training begins as soon as contact with the animal is possible. This may involve play, touch, feeding or, quite simply, trust – lots of trust. A relationship is built gradually, and through that relationship, behaviours can be developed that may prove useful later.

This might involve teaching an animal to stand in a particular position or to remain calm while zookeepers are nearby. If an animal arrives from somewhere else, training often begins during quarantine, where the first steps are taken towards building trust with people and zookeepers.

When the animal is ready, the more formal training begins. This is commonly known as clicker training. In scientific terms, the learning involved is known as Operant conditioning and Classical conditioning.

Put simply, clicker training works by rewarding – and thereby reinforcing – behaviour that we want to see again. Behaviour that we do not want repeated is not rewarded.

To tell the animal exactly when it has done the right thing, a tool known as a marker is often used. This can be a clicker, a whistle or simply a word such as “good”. Almost any sound can be used, as long as the animal does not already associate it with something else. Most animals, for example, will never have heard the sound of a clicker before the day their training begins. For an animal such as a snake, which cannot hear airborne sounds in the same way, a flash of light can be used as a marker instead.

Once a suitable marker has been chosen, the animal learns to associate it with something it wants, usually food. The process is simple: click, give food; click, give food. After this has been repeated a few times, the animal learns that the click means a reward is on its way. The advantage of the clicker is that it allows the trainer to mark the exact moment the animal performs the desired behaviour.

Another commonly used tool is a target stick. This is a stick with a small ball at the end, which the animal learns to touch with its nose, forehead or paw. Once the animal has learned this – which often happens quickly – the target can be used to guide it to a particular place.

This might be into a transport crate, onto a set of scales or simply from one place to another. By working gradually in small steps, the desired behaviour is built up until the final goal is reached. This process is known as shaping.