Considerations for Devising New Techniques
The device must not pose any threats to the
animals safety (Bloomsmith et al 1991). Therefore;
- It should not contain holes that digits or other bodily appendages can
get stuck into.
- It should be able to withstand severe physical abuse by the animal
species without breaking.
- It should not be made of a material that would be toxic if the animal
managed to chew or gnaw pieces of the device.
- It should not be of a size that could be swallowed by the animal.
- The device should not contain any parts in which the animal could either
become entangled or strangulated.
Thus, all devices should be assessed for
safety and where appropriate undergo abuse tests (simulations of destructive
children getting their hands on the device). Free hanging ropes are potentially dangerous
in the enclosure of any species, since animals may become entangled and strangled; thus
both ends of a rope should be attached to a solid structure.
The device must not be able to be used as a weapon by
a particular species on other occupants of its enclosure, against keepers, or the visiting
public (Bloomsmith et al 1991). For example, certain chimpanzees are notorious throwers of
objects (Goodall 1986) as are some elephants (Dittrich 1984); this is especially important
if the object is large and heavy. It is important to remember that food can also be used
as a weapon; for example, imagine being hit by a whole turnip thrown by a chimpanzee!
The device must not have any potential to be used by
the animal to escape its enclosure. For example, devices that have long sections must be
installed in such a way that they could never be used for escape. In a number of cases
chimpanzees have used enrichment objects in their enclosures to scale the perimeter fence
of their enclosure (Dittrich 1984).
It is important to remember that with certain species;
keepers have little control over them; for example, polar bears. Therefore, devices that
must be retrieved from the enclosure for refilling are of little use. In the middle of the
Chimpanzee enclosure at Edinburgh Zoo there is an excellent artificial termite mound
(1982), which many of the chimpanzees like to fish from. However, to refill the termite
mound keepers must enter the outdoor enclosure, but the chimpanzees rarely co-operate by
Certain species have great dexterity and patience for
solving problems, which may be used to dismantle enrichment devices making them of little
value (e.g., all of the great apes, especially the orang-utans). Furthermore, a fully
assembled enrichment device may pose no threat to the animal, whereas a dismantled one may
be dangerous or used as a weapon or to escape the enclosure. Thus, where appropriate very
strong locks should be fitted on enrichment devices.
Devices should be cheap to construct and of the
simplest design possible, so that they are as widely available as possible. Spending much
money on one enrichment device is not cost effective.
In countless zoos throughout the world enrichment
devices are sitting unused, because they are not very practical. Thus, all enrichment
devices should be cleaned, maintained and easily filled, as keeper time is often limited
It is important that enrichment devices installed in
animal enclosures, do not block or obstruct keeper access to the enclosure (Markowitz