Rhino Husbandry Manual
Greater One Horned Rhinoceros
Enrichment
A planned and implemented enrichment program can contribute to better health by providing animals with opportunities to exert some form of control over their environment (Carlstead and Shepherdson, 1994; Baser, 1998). As it pertains to zoo-managed rhinos, we strive to encourage species-specific behaviors in rhinos while providing them response options to environmental change. This will ultimately result in their mental stimulation and the development of naturalistic behaviors (Swaisgood and Shepherdson, 2005)
Each institution may have its own set of goals and criteria for its program, which fundamentally should start with an examination of the animal’s natural history, activity patterns and behaviors seen in the wild. For greater one horned (GOHR) rhinos, pools provide an important form of environmental enrichment. Since rhinos spend the majority of their day eating, keepers could look at modifying feeding schedules or providing enrichment throughout the day rather than just once a day. Keepers also could investigate the possibility of changing group composition at some facilities. Holding facilities, exhibit spaces and/or any constraints that may be unique to the facility should be examined since these areas will directly impact options for enrichment. The temperament and behavior of the specific individual(s) also needs to be taken into consideration. Once these criteria have been reviewed, a set of goals can be established. Generally speaking the primary goal should be to “promote opportunities for the expression of species-appropriate behaviors” (Joseph and Sevenich, 1999). The Rhinoceros Husbandry Resource Manual (Fouraker and Wagener, 1996) clearly delineated the various functions enrichment can serve, such as (1) improving the wellbeing of the animal by increasing exercise, satisfying behavioral needs, and optimizing the level of stimulation that animals receive; (2) educating zoo visitors by increasing the levels of natural and interesting behaviors, visibility and activity levels; and (3) conserving endangered species by improving the success of breeding and reintroduction programs. Through these functions, there are two goals of enrichment, a) the promotion of opportunities to express species-appropriate behaviors (Joseph and Sevenich, 1999), and b) creating mental stimulation for the animal(s).
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A successful enrichment program can be briefly summarized as one that:
a) Establishes goals for the program
b) Creates an enrichment approval form
• States the purpose/goal of this enrichment
• Provides a detailed description of enrichment items (construction material, thickness, dimensions, size of holes, etc.)
• Identifies and addresses facility or exhibit constraints
• Identifies and addresses safety concerns
• Cost estimates
c) Identifies approval protocols for enrichment submissions
d) Creates an enrichment calendar (monthly or weekly) to ensure implementation schedule
e) Determines how staff will document and/or track animal response to enrichment offered
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To accomplish the goals mentioned above, an enrichment plan should be tailored with a set of criteria for either the individual or the species in general. The final proposal should then be submitted through the appropriate channels for approval. Ideally, an enrichment approval system should be set up to allow keepers, managers, and veterinarians the ability to assess the proposed enrichment and approve/reject it. Institutions can alter their enrichment scheduling as well as vary the type of enrichment offered (e.g., toy, food, sensory, environmental, behavioral and social) and keep track through their record-keeping or on a barn calendar (Connett, 2009). One of the most intimidating aspects of enrichment is allocating the time to document animal behavior and/ or responses to the enrichment offered, however observations of responses can either be done in a direct or indirect manner as time allows. This data will enable evaluation as to whether the enrichment goals have been met. Since enrichment is dynamic in nature, adjustments can be made at any time so that the most effective enrichment is offered to the animal(s).
Fig. 4.3. Enrichment items, such as a plastic drum, can create a more stimulating environment (photo taken at Cincinnati Zoo and Botanical Garden).
Enrichment can correlate aspects of ethology, psychology and animal husbandry to create a more stimulating environment for the animal (Mellen and Ellis, 1996). This has led to the inclusion of enrichment options in exhibit designs. Exhibit enrichment can be done by varying topography, landscaping, utilizing deadfall and trees, creating dirt mounds, planting vegetation, providing a wallow, and alternating the substrate (dirt, leaf litter, mulch, etc.). Other options (public view versus privacy, shaded area versus sun, etc.) can all provide the animal some control over their environment and the ability to make choices throughout the day. The aforementioned exhibit variables can contribute to effective enrichment, especially when used in conjunction with other approved enrichment activities. For example, novel scents/perfumes/extracts can be used to create a “trail” throughout the exhibit, while holes drilled in deadfall can serve as an anchoring point for browse, and either one can provide the potential for exploration and create options for the animal. The American Association of Zookeepers (AAZK) has created The Enrichment Notebook (Chan, 2004) that provides suggested guidelines and contains information on exhibit enrichment, dietary enrichment and a section on safety considerations. When using enrichment devices that are awkward and heavy, it is important to secure these items safely, not only for the animals, but for keeper staff as well. Fortunately, these somewhat bulky items can be secured safely by using pulley systems and/or other equipment can be used to hoist devices to enable hanging them higher. A synopsis of rhino enrichment options that are currently being used at zoological facilities can be found in Table 4.9.
This table gives suggestions as to the primary area of use as well as its presentation. Note that food items, especially biscuits, treats, and produce, should be fed sparingly. Examples of enrichment type and some options that can be used are outlined below. These options must be used in compliance with a facility’s enrichment protocol, regulation and safety considerations.
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Toy:
• Boomer Ball (Boomer Ball, Grayslake, Illinois)
• Weeble (Otto Environmental, LLC., Milwaukee, Wisconsin)
• Suspended log
Food:
• Scatter food around exhibit to stimulate grazing/foraging
• Place food items in enrichment devices to be randomly dispensed
• Fruits and vegetables frozen in bucket of water
Sensory:
• Use conspecific’s dung for smell (olfaction)
• Play different animal vocalizations or hang bamboo “chimes” for hearing (audition)
• Mount street sweeper brush for touch (tactile)
Environmental:
• Changing substrate (leaf litter, dirt, mulch, etc.)
• Altering daily routine
• Rotating to different enclosure (pen)
Behavioral:
• Training new behaviors
• Training for veterinary procedures
Social:
• Creating mixed species exhibit
• Rotating individuals (add or remove animals when possible)
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Training for husbandry behaviors is not only stimulating for the animal, but it also can provide an invaluable opportunity for the veterinarian to perform diagnostic procedures with potentially less stress and more cooperation from the animal(s) (Dover, et al., 1994). The chapter for training will delve more deeply into this topic.
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Enrichment Table 4.9 Synopis of rhinoceros enrichment ideas
