Biodiversity Management Plan (BMP) for Cape Mountain Zebra (Equus zebra zebra) approved for implementation
The Cape mountain zebra (Equus zebra zebra) is endemic to South Africa. It is a subspecies of Mountain zebra (Equus zebra) which historically occurred in the mountains of the Great Escarpment from the south west of Angola, through Namibia, the Northern Cape of South Africa, and the Cape Fold mountains in the Western and Eastern Cape Provinces. Gradual separation over time resulted in two distinct subspecies, namely the Hartmann’s mountain zebra (Equus zebra hartmannae) to the north and Cape mountain zebra to the south.
Cape mountain zebra numbers declined drastically to less than 60 individuals at the beginning of the twentieth century. These animals were isolated in three locations: Cradock, Kammanassie and Gamkaberg. Conservation action has resulted in steady increases in the overall population numbers and distribution, however the residual effects of the genetic bottleneck currently threatens the long term survival of the species throughout its natural distribution range (NDR).
Cape mountain zebra now occur in a number of genetically depauperate and isolated populations and are threatened by small sub-population sizes, habitat fragmentation and by hybridisation with other equids.
Collaborative and integrated management among stakeholders, as well as public support, is required for effective management of the sub-populations to ensure the maintenance of genetic diversity and sustainable utilisation by the private sector.
Cape mountain zebra have a limited NDR confined to the extreme south-south west of the country. They are a near endemic to the Cape Floristic Region (Boshoff et al. 2015; Hrabar and Kerley 2015; Birss et al. 2015; Hrabar and Kerley 2013), an internationally recognised global Biodiversity Hotspot (Myers et al. 2002).
At the end of 2015, the Cape mountain zebra metapopulation comprised approximately 4,872 individuals in 76 sub-populations throughout South Africa. Apart from the three relict subpopulations occurring on protected areas (Kammanassie Nature Reserve (NR), Gamkaberg NR and Mountain Zebra National Park), Cape mountain zebra have been reintroduced to another 9 protected areas within their NDR and 7 protected areas outside the NDR. Approximately 70% of the population occurs in state owned protected areas (Hrabar and Kerley 2015).
Cape mountain zebra is listed as vulnerable (D1) 1 by the IUCN (Novellie 2008) and recently at the 17th session of the Conference of the Parities to the Convention on International Trade in Endangered Species (CITES) down-listed from on Appendix I to Appendix II , which regulates International trade, and requires a non-detriment finding (NDF) for export permits to be granted. The proposal was made because of the significant recovery in the animal’s numbers – from just less than 100 individual animals in the 1990s to well over 5 000 in 2016, signifying South Africa’s success in the conservation of the subspecies.
During the Cape mountain zebra BMP-S stakeholder consultation workshop held in November 2013, the following desired state for the Cape mountain zebra was developed:
The scientifically sound conservation (including regulation) of an ecologically healthy and genetically diverse metapopulation of Cape mountain zebra.
The vision is an increasing, genetically healthy metapopulation, supporting sustainable off-takes, with an increased conservation value and private sector investment in Cape mountain zebra.
The desired state is underpinned by specific goals which guided the development of the BMP-S. These are:
- Conservation of the Cape mountain zebra meta-population.
- Advancement of knowledge and understanding regarding the genetic diversity of the Cape mountain zebra metapopulation.
- Eliminate genetic contamination due to hybridisation with other equine species and safeguard Cape mountain zebra in their NDR.
- Mitigate and manage the impact of current and emerging diseases.
- Long-term monitoring of Cape mountain zebra meta-population dynamics and habitat.
- Aligned legislation and mandates.
Effective communication, collaboration and coordination among stakeholders.
Objectives of the BMP-S
The prioritised strategic objectives of the Cape mountain zebra BMP-S are as follows.
- To maintain genetic diversity in the Cape mountain zebra metapopulation.
- To implement monitoring and research to inform adaptive management.
- To consistently and uniformly implement legislation, regulations, policies and guidelines.
- To ensure effective communication, collaboration and coordination between stakeholders and the public for Cape mountain zebra conservation.
Benefits of the BMP-S The envisaged benefits of implementing this BMP-S are:
- The Cape mountain zebra population remains stable and increasing.
- Scientifically-sound metapopulation management is implemented, and through this, the full extent of the genetic diversity is represented throughout the population.
- The population is ecologically healthy and secure (including being regulated effectively and efficiently).
- Implementation and maintenance of sustainable off-takes to support the NDF.
- Private sector support and investment in Cape mountain zebra conservation.
Species ecology and biology
- Taxonomic description
- Taxon name: Equus zebra zebra Linnaeus, 1758 (Novellie 2008).
- Common names: Cape mountain zebra (English), Kaapse bergsebra / bergkwagga (Afrikaans), idauwa (isiXhosa), Dou (San), Daou (Khoikhoi) (Skinner and Chimimba 2005).
- Taxonomic level: Subspecies
Groves and Bell (2004) investigated the taxonomy of the mountain zebras and concluded that the Cape mountain zebra and Hartmann's mountain zebra are distinct, and suggested that the two would be better classified as separate species, Equus zebra and Equus hartmannae.
However, Moodley and Harley (2005) concluded that the two taxa could not be described as different species but, on the basis of their nuclear genetic distinctiveness, indicated that it is appropriate to regard them as different subspecies. That is the approach adopted for this BMP-S.
Mountain zebra are medium-sized, striped equids and differ from plains zebras (Equus quagga) in that the dark stripes on the head and body are narrower and more numerous and are without shadow stripes on the hindquarters. Mountain zebra has white underparts with a narrow black centre line extending over the chest and belly, a black tipped muzzle, a distinct dewlap and the markings over the sacral area form a gridiron pattern. The dewlap is more conspicuous in the Cape mountain zebra. Adult Cape mountain zebras have a shoulder height ranging from 116 to 128 cm and weigh between 204 and 372 kg (Penzhorn 1988).
Distribution of Cape mountain zebra
Mountain zebra historically occurred in the mountainous habitats associated with the availability of fresh water on the Great Escarpment from the extreme south west of Angola, through Namibia, the Northern Cape of South Africa, and the Cape Fold belt in the Western and Eastern Cape Provinces (Novellie et al. 2002). A large plain of unsuitable or marginal habitat known as the Knersvlakte, (an area between the northernmost extent of the Cederberg and Bokkeveld mountain ranges, and the southernmost extent of the Kamiesberg mountain range), is postulated by Novellie et al. (2002) to have inhibited gene flow between those mountain zebra occurring to the north and those occurring further south. However, Boshoff et al. (in Skead 2011) suggests that the population segregation may have occurred further north. Irrespective of where the separation occurred, it over time resulted into two distinct subspecies, namely the Hartmann’s mountain zebra to the north and Cape mountain zebra to the south (Refer to Figure 1).
Population statistics and trends
The overall population growth rate of the Cape mountain zebra metapopulation has remained positive (Hrabar and Kerley 2013; Hrabar and Kerley 2015), however, not all sub-populations are maintaining a positive growth rate (Hrabar et al. 2015; CapeNature 2016). The mean annual rate of increase was maintained at 10% from 2002 – 2009, compared to 8.6% from 1985 to 1995 (Novellie et al. 1996), 9.6% from 1995 and 1998 (Novellie et al. 2002) and 8.4% from 1998 and 2002. It should be noted that when assessing population numbers and their changes over time, that due to the unknown error around the estimates for the count of the entire population it is difficult to assess the accuracy of the trends or to be able to put confidence bounds around the increase figures. In total the Cape mountain zebra population is estimated to have increased by 75% (from 2,790 to 4,872 individuals) over the period 2009 to 2015 (Hrabar and Kerley 2015) which translates to an average annual increase of 11%. Historical national population growth figures were as follows: from 1985 to 1995: 8.6% and from 1995 to 1998: 9.6% (Novellie et al. 2004).