Once plentiful across Africa, the Black rhinoceros Diceros bicornis is now classified as Critically Endangered by the IUCN (IUCN Redlist, 2012).
During the last 60 years the Black rhino population has declined by almost 90% reaching a low of 2,410 individuals in 1995. Since then and until recently numbers have slowly increased. This has been due to concerted conservation efforts to protect rhinos from poaching and to metapopulation management including founding or enhancing populations through translocation. At the end of 2012 the estimated number of Black rhinos left in the world was 5,055 individuals.
Diceros bicornis is the only species within its genus; there are four distinct subspecies recognised by IUCN/SCC African Rhino Specialist Group; The European Association of Zoos and Aquaria (EAZA) is working with two of the four subspecies (Eastern and Southern) and is managing them as distinct subpopulations. A viable European captive programme exists for Eastern Black rhinoceros (D. b. michaeli) and a non-viable European captive population exists for Southern Black rhinoceros (D. b. minor) of 1.1 animals. These are planned to be repatriated to Africa. There are no South western (D. b. bicornis) in zoos nor are there any North western (D. b. longipes) Black rhinoceros, which recently became be extinct in the wild (IUCN 2011). Globally there are now 799 D. b.michaeli, making it the rarest of the three remaining Black rhino subspecies (IUCN 2012).
Due to the Critically Endangered status, Black rhinos in European Zoos are under the most intensive level of management, an EEP. The purpose of this programme is to secure a genetically healthy and sustainable captive population which may serve as a backup population for the wild. An international breeding programme was set up in 1966. This breeding programme contains an international studbook and manages the captive Black rhino population (Dollinger and Geser, 2008). The goals of this international breeding programme are self-sustaining reproduction, demographic security and stability, genetic diversity adequate for animal fitness and population adaptability and target population sizes sufficient to achieve these genetic and demographic goals (Foose and Wiese, 2006).
Worldwide there are 240 Black rhinos in zoos, including 64 in 15 EAZA zoos (2012) and another 15 in 2 non-EAZA zoo’s. EAZA members have established Taxon Advisory Groups (TAGs) for different groups of animal species that are kept in zoos and aquariums. One of the main tasks of a TAG is to develop Regional Collection Plans that describe which species are recommended to be kept. The TAGs also identify which species need to be managed in a European breeding programme called EEP (European Endangered species Programme) (EAZA, 2008).
The mission of the EAZA Rhinoceros TAG is:
‘To ensure all captive populations are healthy, self-sustaining and genetically viable and are capable of being an effective tool in support of rhino conservation in the wild.’
The goals of the EAZA Rhinoceros TAG are:
- To ensure each EEP population is self-sustaining and genetically viable in the long term.
- To ensure each taxon has ambitious targets for the retention of maximum gene diversity (~ 90% GD per century).
- To work more closely with other regions to support effective population management.
- To work to overcome obstacles which impinge upon population and genetic management goals; e.g. international transfers and importation of new founders.
Husbandry and welfare
- To ensure each EEP drives ongoing welfare and husbandry improvement.
- To ensure Best Practice Guidelines are in place for all EEPs by 2012 and reviewed at least every second year.
- To develop an audit process to ensure all holders are compliant with Best Practice Guidelines by 2015.
- To identify and support research priorities which advance husbandry and welfare and support the development of Best Practice Guidelines.
Education and research
- To ensure the captive populations provide a significant educational and research resource capable of contributing to rhino conservation.
- To recruit an education advisor to the TAG.
- To measure the impact of zoo based education specific to rhino conservation and assist in the improvement of zoo based education.
- To set up a research advisor team to the TAG.
- EEP coordinators to identify research priorities prioritising projects conceived to improve captive management, reproduction and welfare.
- EEP coordinators to collate research activities.
- Research advisor to report on activities and facilitate TAG wide research activities.