Captive tigers often live in enclosures that vary widely in quality, which have significant implications for the animal’s physical and psychological well-being. Good enclosures are designed to meet the behavioural and physical needs of tigers, providing ample space, structural complexity, and environmental enrichment. Key features of effective enclosures include sufficient size, reduction of straight-line enclosure design to reduce abnormal repetitive behaviours, choice and control over the environment. Such environments allow tigers to express natural behaviours, exercise, and promote interaction with the environment.
In contrast, poorly designed enclosures can lead to detrimental outcomes and are often identified by their small size, inappropriate substrate like concrete, lack of complexity and minimal enrichment. This often causes an increase in behavioural problems, including increased stress, abnormal repetitive behaviours, and physical issues, such as health complications resulting from inadequate space, insufficient enrichment, and inappropriate materials.
Understanding good tiger enclosure design
There are many aspects to consider when designing a tiger enclosure. Here are three basic things to look out for when visiting a zoo and seeing the tiger enclosures.
Large size
Enclosures should provide adequate space for tigers to move freely, exercise, and express a range of natural behaviours. For instance, the enclosure should be large enough to allow the tiger to run at full speed if it chooses. According to the American Zoo Association (AZA) the minimum space requirement for tigers is 144 sqm for just one tiger, but the best enclosures will far exceed this size. By providing a large space, the tigers have the ability to properly exercise and gain muscle, as well as investigate and explore. However, size alone is not enough. A large enclosure with no complexity, will also not meet the needs of the tiger and still cause behavioural and physical issues.
Range of complexity
There are three main aspects to consider when looking at the complexity of a tiger enclosure – shape, furnishings using the 3D space and topography. The combination of these elements helps provide an engaging, varied and novel environment, though these alone are still not enough.
Shape: Changing the shape of the enclosure from rectangle or square designs to designs without sharp corners aids in the reduction of pacing behaviours as the removal of straight-line walking encourages a different walking pattern. Rounded corners and odd shapes create a more natural environment for the tigers to enjoy and are a sign that the zoo or facility is considering this aspect. Such design promotes exploration, which keeps the tiger active in a more positive way.
Furnishings: A range of species-specific furnishings such as platforms, hammocks or walkways should be provided to make good use of the 3D space. These should be provided in multiple locations. This allows the tiger to choose which area of the enclosure to be in rather than being forced into one specific area if it wants to access that item. Platforms should also be above the recommended height of 1 m (3 ft), and the number of items should be appropriate to the number of tigers within that enclosure so that all individuals can choose to use the items separately. Again, this benefits the tigers on a physical level, encouraging a range of movements and getting the tigers to use their muscles for jumping and climbing. Providing alternate routes around the enclosure, high viewing platforms and so on, allows the tigers to engage with their environment mentally, giving them opportunities to observe other locations or figure out how to get about.
Topography: this refers to the design of the enclosure in terms of rocks, hills, bumps and so on. Good enclosures will offer varied topography and include rocky outcrops, hills, and climbing structures fully utilising the 3D space, providing a range of choices in terms of movement and environment interaction. Again, this serves to encourage problem-solving, i.e. how to access a specific resource and reduces the arrival of abnormal repetitive behaviours.
Plenty of shelter
To enhance the well-being of tigers, enclosures should include features that allow them to remove themselves from sight of visitors should they choose. Shelters should also provide tigers with cover from the weather, be it shade when it’s too hot or shelter in heavy rain. Importantly, if there are multiple tigers in an area, they should all be able to share the same shelter space or have options to shelter alone. The ability to access the back of house should not be considered a replacement for having an outdoor shelter area. Providing shelter and the ability to remove themselves from view helps reduce stress and related negative behaviours toward both visitors and other tigers within the living space.
Identifying bad tiger enclosures
With the same three features, here are some basics you can use to spot poorly designed tiger enclosures, those that are not meeting the tiger’s needs.
Inadequate size
One of the primary issues with bad enclosures is the insufficient space provided for tigers to engage in natural behaviours. This can cause both mental and physical issues. Tigers can lose muscle mass due to restricted movement and a lack of opportunity to run or climb. Mentally, they can be impacted by the small size, and they are unable to travel distances, explore, or investigate as they would in the wild. Moreover, enclosures with high walls and inadequate climbing opportunities may contribute to frustration and abnormal behaviours, such as pacing or aggression.
No complexity
Again, considering the three components used above to look at complexity, what can impact the level of enclosure complexity for captive tigers?
Shape: rectangular or uniform geometric shapes lack complexity, encouraging tigers to follow set paths and begin stereotypic route tracing. The lack of any features that cause the tiger to deviate from their set path results in these repetitive behaviours.
Furnishings: no furnishings such as a multi-level platform or walkways do not encourage a wide array of physical movement or behaviours and is poor use of the 3D space. A lack of a platform, or only a small one with a single level, also prevents tigers from having an adequate sunbathing or viewing spot. And, even if there is a platform, just one among many tigers is simply not enough to provide all tigers with the opportunity to perform a range of behaviours.
Topography: flat topography throughout the living space does not provide challenges within the environment. Again, this impacts how the tiger will move about the enclosure, with a flat, unvaried topography offering little in the way of a natural habitat.
This design, or lack of design, severely restricts choice for tigers, offering no complexity or choice when interacting with the environment.
Lack of shelter
Enclosures that do not consider environmental impacts can lead to further challenges. For example, enclosures that lack natural elements such as shade or shelter can expose tigers to extreme weather conditions, compromising their health. The tigers will be open and exposed with nowhere to go, which can be very stressful. Additionally, small enclosures with too much dense vegetation, while offering some shelter and shade, can create hazards and prevent the display of natural behaviours such as running.
What else?
Of course, there are many other points and features to consider when designing a tiger enclosure. These are simply some of the basic, more obvious ones. Proper enrichment programs, nutrition, options for privacy, naturalistic environment and appropriate behavioural interactions are all part of the complex way we can improve the lives of captive tigers.
For now, understanding some of the basics can help regular visitors demand better for captive tigers and ensure better welfare regulations and zoo standards are put in place.
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