More room for the biggest animals

Kaeng Krachan Elephant ParkMore space for the elephants, more proximity for visitors. The new Kaeng Krachan Elephant Park marks a further milestone at Zoo Zurich. While the elephants move around more freely, maintain social contacts and even go swimming, the public will have the chance to get closer to the animals than ever before.

The new Kaeng Krachan Elephant Park at Zoo Zurich has opened its doors to zoo visitors. The impressive compound in the eastern part of the zoo will allow members of the public to see the elephants from a completely new perspective. Visitors will be able to observe the mighty animals reacting socially with one another and look on as the elephants eat at various different food points in their landscaped new compound. The elephants can even be seen swimming from a special underwater viewpoint.

Water plays a significant role in the new Kaeng Krachan Elephant Park. A number of different pools and showers are provided for the elephants both inside and out. The animals make active use of these facilities. Elephants are good swimmers. They are used to crossing stretches of water out in the wild, and often bathe in water in order to regulate their body temperature and look after their skin. Now they can do the same in their new compound.

Protection of their wild relatives

The new elephant park is named after the Kaeng Krachan National Park in Thailand, where Zoo Zurich supports a project to help protect Asiatic elephants. Resolving the “human-elephant conflict” that opposes farmers and elephants is an important aspect of the project. The conflict is due to the extensive damage caused to plantations by wild elephants as they move from one part of the protected zone to another. Protective fencing is being used to remedy the situation. A series of exhibits at the Kaeng Krachan Elephant Park at Zoo Zurich shows visitors what the protective fencing looks like and how it works.

A new era in elephant keeping

Zoo Zurich’s six elephants have been living in the Kaeng Krachan Elephant Park since the middle of March. This has given them plenty of time to get used to all the innovative features of their new environment. Firstly, they have six times as much room as they did before, as well as several different watering holes for swimming and bathing. The new park offers the elephants a lot more opportunities for moving around in different ways, and enables them to live together naturally as a family group. Secondly, the way in which the animal keepers look after the elephants has also changed. The animals are now cared for in “protected contact” at all times. This means that the animal keepers are no longer in the same room as the elephants. This gives the animals more freedom to develop their social structure and ensures greater security for the animal keepers.

What is more, the group of six elephants at Zoo Zurich is set to increase in size. A second bull will be moving into the elephant park shortly to keep MAXI (*1969/70) company. In addition, INDI (*1986) is expecting her third calf. It will soon be joining CEYLA-HIMALI (*1975), CHANDRA (*2002) and FARHA (*2005), the group led by head cow DRUK (*1967).

An extra large construction project

The Kaeng Krachan Elephant Park and the Masoala Rainforest together form a special new focus area in the eastern part of Zoo Zurich. This represents the framework and background for the future African Savanna extension in the Klosterfeld area that will one day be linked to the elephant park. The new compound measures around 11,000 square metres. The elephants have around six times more space in their new home than in their old enclosure.

Luxuriant mixed woodland developed from the surrounding Züriberg forest forms the setting for the new compound. It marks the transition between the sparse African Semien Mountains and the beginnings of a thriving, green river valley. Meandering its way through exquisite topography, the main path leads through the wood to the new section of the zoo. Visitors then find themselves in the world of the elephants some 15 or so metres below. In amongst the thickets of bamboo, visitors catch their first glimpse of the dried-out river bed of the elephant valley with the elephant house in the background.

The overall landscape and architectural concept is based on the interplay between light and shadow. Vegetation has been planted to form a succession of different themes in the style of Thai vegetation compositions. The effect continues inside the elephant house, encouraging visitors to forget the boundary between inside and out. The main focus for visitors is the area around the lodge, which forms the interface between the indoor and outdoor enclosures.

Inside, visitors can enjoy various different viewpoints as they follow a path beneath tropical trees. One of these is the underwater viewpoint, from where they can see the elephants swimming. There are several bends in the enclosures, both inside and out, with cavities and protuberances. It is impossible to see the whole compound in one go – the space appears to go on forever.

Elephant parcPowerful and sustainable

The new Kaeng Krachan Elephant Park needs a great deal of power. This implies having substantial technical facilities, all of the extra-large variety. The equipment – such as facilities for air conditioning, ventilation and water treatment and the electrical supply – is mostly located in the basement. It remains largely invisible to visitors.

Great emphasis was placed on sustainability during the construction of the compound. The main building material was wood. Heating is provided via a district heating network using the central woodchip heating system at Zoo Zurich. Rainwater is collected from the roof, which measures 6,800 square metres. The water is then used for watering the ground, for moistening the sand, for removing dust from the plants and for supplying the pool maintenance equipment. Finally, an ingenious event control system ensures that the air conditioning in the inner compound conserves natural resources as much as possible.

The roof: spectacular from start to finish

The 6,800 square metre roof is a particularly spectacular part of the new compound. It was designed as a flat, freely-shaped wooden frame. It is a net-like, transparent organic structure that is in harmony with the surrounding woodland. The hall has an overall diameter of 80 metres. The roof does not require any wooden columns or support structures of any kind inside.

Light in the hall is provided by 271 skylights made of UV-permeable ETFE foil covering an overall surface area of approximately 2,100 square metres. Inside the hall, this gives the impression of being in a park under a canopy of leaves, which again emphasises the “natural” aspect of the elephant park. All the different parts of the construction were developed using a special 3D computer model. A roof model was built on a scale of 1 to 200 to test structural analysis and construction data. The findings were then incorporated into the calculations. An additional roof cut-out of the entire roof structure including waterproofing and skylights was built later on, on a scale of 1 to 1.

Scaffolding had to be set up over the entire hall before the wooden frame of the roof could actually be built. Thanks to this scaffolding, beams that had been measured right down to the last millimetre were assembled to form an inverted mould of the future shape of the roof. The three-layer panels were then assembled over the beams in three layers to form the roof shape. Each of the 600 three-layer panels that had previously been cut to shape was then positioned in its precalculated position on the roof. For stability reasons, the first layer of the three-layer panels was placed over the entire surface. The skylights had already been cut out of the second and third layers. Once all three layers had been positioned on the roof, the three three-layer panels were nailed together with nails (approx. 22 tonnes / 500,000 nails) and special nailing machines.

Screws were used in the remaining construction process as well as large amounts of wood and more nails. Approximately 500,000 screws of 15 to 85 centimetres each were needed. Once completed, the roof is around 90 centimetres thick and weighs around 1,000 tonnes. As well as providing weather protection and heat insulation, the roof plays a structural role and has wires running through one level.