Burgers' Zoo is known for its eco-displays: nature reserves where animals often live in great freedom amidst thousands of plants, and visitors can experience such a habitat up close. An eco-display is designed to imitate a specific ecosystem as realistically as possible. What does that mean in practice? What are some of the characteristic features of an eco-display? What do biologists and designers need to consider when designing an eco-display? What challenges do they face? In this series, we focus on the essence of each eco-display through practical examples. This time: the Desert.
Burgers' Desert is the largest American rocky desert in the European zoo world. Visitors are introduced to the deserts of the southwest of the USA and northern Mexico. Our Desert is a combination of the Sonoran Desert in Arizona and Mexico and the Mojave desert in California. Because the American rocky desert is not located in the tropics, it has quite defined seasons. It can be scorching hot in the summer and quite cool in the winter. This desert also experiences an annual period of short, heavy rainfall, after which all kinds of smaller plants suddenly shoot up, covering the landscape in a carpet of green. The temperature varies greatly during the day and night; especially in summer, the differences are extreme.
We heat the Desert to ten degrees Celsius for our visitors in winter. However, we do not cool the Desert in the summer. In the record summer of 2020, a temperature of over 40 degrees was measured, even in the shade! We can open a large door with a mesh screen in front of it so that the animals cannot escape, and some shutters can open too, also with mesh screens.
Deserts are extreme habitats, and animals and plants living there need to minimise their water consumption. Many animals have very concentrated urine, and various plant species such as cacti have techniques for storing water. Since desert plants generally grow very slowly, we protect our plants from being eaten by various animal species. Other challenges in the Desert are that some species have other animals on their menus, such as roadrunners or the bobcat. We keep these species separate from their potential prey. Songbirds can be quite territorial, so we cannot release too many birds of the same species in the Desert.
The design of the Desert cleverly uses landscape elements to hide visitors from view. The trails wind between rock formations and sometimes plunge into caves with animal enclosures before leading past canyons or dry riverbeds. The strategically placed natural landscape elements ensure that visitors walking on a different path are temporarily invisible. Our former zoo designer Tom de Jongh travelled to the Sonoran and Mojave deserts. He took many pictures, thoroughly examined the landscape there and then modelled a very precise clay model, after which the authentic landscape elements were recreated very precisely. Experts designed, crafted, and painted artificial rocks to achieve the truest representation possible. Doors to animal enclosures are often cleverly incorporated into the rock walls to cause as little disruption to the design as possible.
Other landscape elements that give the Desert its distinctive character are, for example, the recreated rock paintings made by the original human inhabitants of these desert areas some five thousand years ago. Or the authentic fossilised tree trunks, as found in the Petrified Forest in Arizona. The simulated excavation of the skeleton of a Tyrannosaurus rex, the 'crashed' wooden car in the middle of the desert, and the abandoned campfire in the rattlesnake enclosure are other typical landscape elements.
But don't forget the extraordinary plant collection in the Desert! The impressive, metres-high saguaros (columnar cactus) immediately catch the eye, as do the characteristic yuccas, agaves, discocactus, the Joshua trees and the creosote bushes. The old man cactus and the mother-in-law's cushion are endangered species in the wild. Without a watering system built into the Desert's roof, the plant caretakers manually water the plants. Many desert plants can, of course, withstand long periods of drought and know how to store the sparse rainfall conveniently and efficiently for later use.
Some desert dwellers have good defence mechanisms. Certain plant species produce toxins to protect themselves from being eaten, and animals such as the red diamond rattlesnakes and Gila monsters are venomous. The red diamond rattlesnakes are subject to an extensive care protocol, including training the zookeepers in case someone is bitten. Fortunately, at the time of writing, this has never happened in the history of our Desert.
It is impossible to explain all the special features of the Desert eco-display in one article. Still, this text offers several concrete points of interest to pay extra attention to during your next visit to our rocky desert. Hopefully, this will also lead to a better understanding and appreciation of this special eco-display, which shows a habitat that can only be admired in a few zoos.