Gregory J. Fleming^† and Michelle L. Skurski

Enrichment

Enrichment is more than just placing a new branch or a plant in a reptile’s environment. Although there are many different definitions of enrichment, for the sake of consistency, we will follow the definition used by the Association of Zoos and Aquariums (AZA):

In practice, enrichment means encouraging species-appropriate behaviors and providing the animal with choices in every aspect of reptile husbandry, from food presentation to housing. The diversity of reptile habitats, microhabitats, and ecosystems, as well as the range and complexity of their behaviors, can actually increase the opportunities for enrichment to enhance the animals’ lives.

Based on the aforementioned definition, there are three main goals for enrichment:

All three of these goals require a clear understanding of the animals’ natural history. This information is critical to making the enrichment successful. Based on the natural history, each enrichment initiative should have a behavioral goal. One benefit of setting behavioral goals for enrichment is that it offers a way to measure our success. For example, a client may want to encourage an overweight arboreal snake to climb and utilize more of the enclosure. The question the client would ask is, “Did the addition of branches into the snake enclosure encourage the snake to climb and utilize the enclosure?” If the answer is yes, the behavioral goal was achieved. If the answer is no, then other options such as platforms, heat sources, or even different types of branches may be explored to encourage the snake to climb (Figure 11-1).

Another behavioral goal may be to encourage an animal to forage. For instance, natural scents can be provided by dragging a prey item through the enclosure to leave a scent trail that can stimulate the reptile to forage. Sometimes the scent just needs to be novel to engage the reptile. Keepers have successfully utilized a cinnamon scent trail scattered throughout an enclosure to encourage foraging in a Komodo Dragon.

Choice of housing, enclosure furnishings, and behavioral opportunity depend on whether the reptile is arboreal, terrestrial, aquatic, or semiaquatic. Something as simple as providing different levels in an enclosure can encourage exploration and foraging. Many species of monitor lizard are known to stand bipedal to forage in the wild. This behavior can be recreated through minor alterations of an enclosure and delivery of food to the animal (Figure 11-2). Although animals in the wild seem to exhibit this behavior without much effort, a monitor lizard in captivity may need to be encouraged to stand through small and successive approximation. Captive lizards are likely novices at standing and will need to develop the skills and physical ability to accomplish some behavioral goals.

The way in which food is presented can also provide behavioral opportunity. Multiple behaviors can be encouraged by varying the size of the food item, the placement or location of the food, and the time of day of the feeding. For example, tree pythons are nocturnal; as such, their activity level typically increases at night. During the more active periods, foraging and hunting behaviors will be displayed. Therefore feeding during these periods could encourage active behaviors that stimulate and exercise the snake.

Providing complexity and choices to an environment can be achieved through addition of or changes to rocks, branches, plants, light, and substrate within an enclosure. Providing choices for and control over thermoregulation opportunities is vital for the reptiles. Opportunities for thermoregulation can be provided with the use of lights, undercage heat pads, water of different or variable temperatures, and heat-emitting ceramic bulbs. Recently, improvements in technology allow changes in the temperature and humidity of captive enclosures by the minute. Environmental temperature and humidity may be altered on a daily basis, which allows for natural changes in the animal’s environment that mimic a natural sunrise or an afternoon rainstorm.

Offering different levels in an enclosure provides reptiles an opportunity to utilize heat and light sources to varying degrees. Understanding the general environment for the reptile in the wild is not enough; a reptile caretaker must dig a bit deeper to meet the animal’s needs. For instance, the animal could come from the desert but spend the majority of its day burrowed underground escaping from the sun and heat. In this case, the assumption that the animal would need a very warm, barren environment would take into account only a part of its natural history. Providing a way to escape the heat would also be vital to this animal’s well-being. Appropriate lighting is essential not only for health but also for enriching a reptile’s life.

Encouraging your clients to study the natural history of the species they care for will be the first step in the creation of a successful enrichment program for their reptiles. Enrichment done appropriately will improve the health and well-being of the animal, enhance their welfare, and assist in facilitating their care. To find some additional examples of enrichment ideas, see Disney’s Animal Programs’ enrichment Web site at www.animalenrichment.org.¹