Rhino Husbandry Manual
Greater One Horned Rhino
Management
Group Management in Captivity
The greater one-horned rhino is generally considered more solitary than white rhinos, though there is evidence that they are at least as social as black rhinos if not slightly more so (notably in captive scenarios). If given adequate space, females, calves, and juveniles will often seek each other out. This is commonly observed in "large acreage facilities" but has also been possible in some more traditional zoo settings. Apart from cow-calf pairs, groups are rare (Laurie, 1982). Data on rhinoceros social organization, combined with preliminary analyses of parameters affecting reproductive success in captivity, may be used to generate recommendations regarding possible social groupings in the zoo setting (Tables 4.1 and 4.2). Many variables affect the probability of success for any zoo-managed social group, including the animals’ dispositions and available holding space. Further, depending on space and animal and staffing availability, institutions may hold animals for breeding or for exhibit only. Facilities that wish to hold rhinos for exhibit purposes only are advised to maintain two animals (male.female: 1.1 or 0.2 or, more recently, 2.0 because of the skew in male births, as well as the inability to house more than one, or possibly two, males at the breeding institutions).
For institutions that have the space and staff available for rhino breeding, it is recommended that managers commit to two pairs of greater one-horned rhinos. In addition, breeding institutions must also have space for offspring to be held for up to three years after birth. Within a single exhibit or holding area, the recommended minimum numbers for breeding are 1.1. In general, it is recommended that mature males not be held together because of the increased likelihood of serious aggression. Furthermore, males and females of this species should be kept separately and introduced only for breeding purposes.
Grouped or multiple-species exhibits are possible for greater one-horned rhinos if ample exhibit space is available. Examples of institutions that have successfully maintained mixed species exhibits include San Diego Zoo Safari Park, the Wilds, Lowry Park Zoo and Riverbanks Zoo. Species that have been successfully paired in an exhibit with rhinos include sarus cranes, herons, some antelope species (nilgai, blackbuck, gaur, Persian goitered gazelle), mouflon, zebra, and some deer species. In all cases, the dispositions of the individual animals, as well as adequate space and exhibit structure (i.e., visual barriers, refuge areas, etc.), are important to consider prior to attempting a mixed-species exhibit.
Table 4.1 Possibilities for rhino social groupings within the same exhibit in captivity
Multiple animals of same sex
Multiple animals of opposite sex
Species
Adult Males
Adult Females
White
RARE- Depends on habitat size
Recommended
Possible and recommended for breeding
(optimal: one male and two or more females); if possible, an additional male in proximity but not in same enclosure
Black
Not recommended
Successful in related females in test groups.
(See Cleveland Metroparks/Blank Park Zoo)
Possible and recommended for breeding (optimal: 1.1)
Greater One Horned
*Possible with juvenile males but has not occurred "long-term" yet (Cseplo)
The smallest of the "large acreage facilities" averages 10 acres. It has also been achieved in more traditional zoo settings such as Basel (two outdoor exhibits that are 1000 m² and 500 m² respectively) (Cseplo, 2023)
Pairings recommended only during peak estrus (with the exception of very large exhibits, which may hold a single male and
female together consistently)
Identification
Although physical characteristics such as horn size and shape make individual rhinos fairly easy to distinguish from one another, sound rhino management requires that animals be identified through permanent and reliable methods. Trovan® transponders (Electronic Identification Devices, Ltd., Santa Barbara, CA), implanted at the base of the left ear during post-natal examination or as soon after birth as possible, provide a means of permanent primary identification for all individuals. Adults should be transpondered opportunistically. Transponder numbers need to be reported to the studbook keeper. In addition to a transponder, each individual should have a secondary visual means of identification, such as an ear tag or ear notch. Photographs or sketches in the animal’s records may also serve this purpose.
Keeper Training and Interaction
As with any position involving the management of large animals, rhinoceros keepers should have as much formal training and experience as possible and should be familiar with rhino behavior and husbandry. In order to ensure safety and to properly meet the requirements of management, it is recommended that more than one keeper be responsible for the care of these animals on a daily basis. Keeper interaction should be restricted to designated areas and should be conducted in accordance with institutional protocols. Finally, consistency of routine is vital. There are no conclusive data to indicate the effects of different styles of keeper interaction on rhinoceros behavior or reproductive success in captivity. Interaction styles range from no contact at all to daily hands-on contact. In an effort to create an environment patterned after the wild, however, at no time should relationships with keepers substitute for natural interaction among individuals. It is important that rhinoceros personnel keep a daily log, noting any unusual behavioral or physical changes. It is the responsibility of management to supply all pertinent data to the studbook keeper.
Daily Regimen
Fresh water should be available at all times and should be changed daily or supplied by an automatic-fill or continuous-flow device. Regular cleaning and disinfecting should occur at a rate that inhibits the growth of algae and bacteria. Water devices should be constructed to prevent upset, spillage or leakage. Rhinos need access to water pools and/or mud baths to keep their skin healthy; mud wallows should be renovated periodically to prevent contamination (see Enclosure Design chapter for more information on pools and wallows). Natural substrates in confined areas (e.g., holding corrals) can be spot-cleaned daily, but daily removal of feces from larger enclosures is not necessary as defecating at dung piles is an important natural behavior (Laurie, 1982). Hard-surfaced areas not exposed to the elements should be drycleaned or hosed daily and disinfected at least weekly. Indoor housing surfaces, as well as walls and rub areas, should be cleaned daily. Additionally, the daily hosing or showering of rhinos in the barn with temperature-controlled water is recommended to promote healthy skin during the winter months. In order to facilitate participation in many research programs involving rhinos, it is recommended that institutions implement training programs following the protocols recommended in the Training chapter. Additionally, it is recommended that some form of environmental/ behavioral enrichment be integrated into daily rhino management.