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Home , Drakensberg, Fynbos, Grey rhebok, Harpochloa, Leucosidea, Merxmuellera

HABITAT SUITABILITY ASSESSMENT OF TS’EHLANYANE NATIONAL PARK, : VEGETATION DESCRIPTION AND RECOMMENDATIONS FOR WILDLIFE INTRODUCTIONS

Compiled by

ME Daemane, Charlene Bissett, Lourens de Lange & Hugo Bezuidenhout

Conservation Services, Kimberley, SANParks

February 2017

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1. BACKGROUND

The Ts’ehlanyane National Park (TNP) was first established by Earth Plan consultants in 1997 to be developed as a nature reserve for conserving the representative fauna and flora of the Alpine Belt. In 2000 the nature reserve was handed over to the Development Authority and in 2005 the Government of Lesotho in the Ministry of Tourism Environment and Culture took over the management of TNP. The park is located in the of Lesotho deep in the front range of the Maluti at the junction of the Ts’ehlanyane and Hololo rivers (Figure 1). TNP encompasses approximately 5 392 hectares of extremely rugged mountainous terrain and it is the second largest Protected Area in Lesotho (Figure 1). It has an altitude ranging from 1940 to 3112 meters above sea level and is considered mostly sub-alpine. It owes its origin to the access road to the Hlotse tunnel as part of the Lesotho Highlands Water Project. TNP has exceptional scenic, natural and wilderness features. All large mammalian fauna were extirpated from TNP in the early 1900s (Morake 2010; Boshoff & Kerley 2013). The first faunal introduction into TNP was achieved in 2008. A game fence was erected around a 426ha area within the TNP in preparation for the first faunal introductions from South (Figure 2).Toward the end of 2008, donated 10 eland ( ) to TNP and a further 15 eland were introduced from South Africa in 2009 to supplement the first introduction.

Figure 1: Location of Ts’ehlanyane National Park, Bokong and Sehlabathebe within Lesotho. Neighbouring South African provinces are also presented.

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1.1. Objective for the assessment The Maluti Transfrontier Programme (MDTP) and stakeholders requested a team of experts from Lesotho and South Africa to undertake a habitat assessment that will assist in the decision making regarding the request for zebra (Equus /Equus zebra zebra) donations to TNP. This request also follows a previous game donation by South African National Parks and Economic Development, Tourism and Environmental Affairs where 25 eland were donated to TNP.

2. HABITAT ASSESSMENT

A team of experts from South Africa and Lesotho led by MDTP Conservation specialist undertook a habitat assessment in TNP from the 30 January to 03 February 2017. The field work was aimed at assessing the feasibility for new game introductions by verifying the landscape features such as vegetation type, associated biomass and forage availability; size of the park; water availability; staff capacity and general challenges associated with management. Two days were set aside for field assessments. The area covered during these field assessments are shown in Figure 2.

Figure 2: The area covered during the habitat assessment in Ts’ehlanyane National Park, Lesotho.

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2.1. Vegetation

TNP falls within the and is dominated by herbaceous vegetation of relatively short and simple structure, usually of the family (Mucina & Rutherford, 2006). Woody are confined to specific habitats such as smaller and drainage lines.

2.1.1. Bioregions TNP falls within the Drakensberg Grassland Bioregion, consisting of three vegetation types: Drakensberg-Amathole (Gd 6), Lesotho Highland Basalt (Gd 8) and Drakensberg Afroalpine Heathland (Gd 10) (Figure 2).

Drakensberg-Amathole Afromontane Fynbos (Gd 6): dominated by small and shrubs in steep valleys and slopes, stream gullies, and depressions. Lesotho Highland Basalt Shrubland (Gd 8): the landscape consists of many plateaus and high ridges of mountains separated by deep valleys. Drakensberg Afroalpine Heathland (Gd 10): found in the highest plateaus and ridges above an altitude of approximately 2900 metres above sea level (masl). The frost action is important in alpine soil formation, where the freezing and thawing of the soil heaves the soil material, resulting in gradual removal of finer soil particles downslope.

Figure 3: The Drakensberg Grassland Bioregion consisting of three vegetation types in Ts’ehlanyane National Park Lesotho. Source data: Mucina & Rutherford 2006.

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2.1.2. Delineation of communities

A broad vegetation classification, description and mapping is useful at a broader scale, however finer refinement is still required at a local scale (i.e. park scale) to divide the park into plant communities. Vegetation sampling previously undertaken by Lesotho officials were used together with data collected in January 2017 to identify the most dominant plant communities and associated habitats. Vegetation types by Mucina & Rutherford, 2006 (Figure 3) were realigned with landscape features using Google Earth Pro for accuracy and three plant communities were identified (Figure 4).

1. Leucosidea sericea - Buddleja salviifolia Shrubland This plant community occurs in the Drakensberg-Amathole Afromontane vegetation type. The drainage lines and the footslopes are mostly dominated by Leucosidea sericea. The drier areas outside the drainage lines are dominated by divaricata, Passerina monticola, Rhamnus prinoides, Diospyros austro-africana, Artemisia afra and Buddleja loricata and Buddleja salviifolia. The reed, Thamnocalamus tessellatus occasionally occur on the footslope but are more abundant on the midslope valley. The most dominant grasses are Cymbopogon excavates, Aristida congesta subsp. barbicolis, Merxmuellera macowanii, Hyparrhenia hirta and forbs such as Helichrysum and Senecio .

Figure 4: Finer delineation of the Drakensberg Grassland Bioregion resulted into four plant communities in Ts’ehlanyane National Park.

2. Passerina montana Shrubland This plant community consists of plateaus and high ridges of mountains often separated by deep valleys in the Lesotho Highland Basalt Grassland vegetation type. Vegetation is closed, short grassland with many areas dominated by Passerina montana, Searsia pyroides and

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Chrysocoma ciliata. The depressions are dominated by Leucosidea sericea and Buddleja loricata. Themeda triandra, Helictotrichon longifolium and Cymbopogon excavatus tend to be more dominant at the lower and middle elevations whereas Merxmuellera disticha occurs at higher elevation.

3. Themeda triandra – Festuca caprina Grassland This plant community tends to be more dominant on the middle and high elevations in the Lesotho Highland Basalt Grassland vegetation type. The middle elevations are dominated by Themeda triandra, Cymbopogon excavatus, Harpochloa falx, Elionurus muticus, Pentaschistis oreodoxa, Eragrostis chloromelas, Eragrostis racemosa and Eragrostis capensis. Leucosidea sericea is encroaching some areas in the middle elevations possibly due to lack of fire in the area. The higher altitudes are dominated by Festuca caprina, Heteropogon contortus, Pentaschistis oreodoxa, caffra and Merxmuellera disticha. Eland seem to mainly utilize this plant community as a lot of droppings were encountered in this area. A herd of approximately 23 eland were seen utilizing these areas on the 2nd February 2017 (Figure 5).

Figure 5: A herd of eland, approximately 23 individuals, utilizing the Lesotho Highlands Basalt Grassland in Ts’ehlanyane National Park. Photo: Lourens de Lange.

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4. Helichrysum trilineatum - Chrysocoma ciliata Heathland

This heathland community occupies a narrow strip at the edge of the escarpments in the Drakensberg Afroalpine Heathland vegetation type (Killick 1963). Short shrub-dominated vegetation such as Helichrysum trilineatum, species and Chrysocoma ciliata are interspersed with alpine grassland such as Merxmuellera disticha, Mermuellera drakensbergensis and Festuca caprina. Cushion plant species forming low mats such as Helichrysum species are also common.

2.3 Fire

Grassland is a fire-prone ecosystem and fire therefore plays a crucial role in the maintenance of vegetation structure and plant species composition (Mucina & Rutherford 2006). Fire suppression may also result in vegetation transformation such as a succession trend from an herbaceous forbland towards a shrubland structure and plant species composition. The key components of a fire regime in the grassland ecosystem are the frequency, seasonality and intensity of fires (Gill 1975). Fire in occurs every 1-4 years and, in montane grasslands, occurs mostly in late winter from July to September (Le Maitre & Midgley 1992). Fire intensity depends on fuel moisture, air temperature and wind speed. Lightening is also the primary natural source of ignition for grassland fires. Factors such as rainfall and fire regime will therefore play a major role in influencing vegetation structure and plant species composition in TNP.

2.4 Water in the landscape

The park is located deep in the front range of the Maluti Mountains at the confluence of the Ts’ehlanyane and Hololo rivers. Besides these two main rivers, there are several tributaries originating from the steep, upper midslopes providing enough water for the wildlife especially during the summer season. Snow is a common feature during the winter months and this provides extra precipitation providing water during the dry season. Furthermore, an artificial waterhole has been erected by the contractual partners in front of Maliba River Lodge.

2.5 Historical distribution of large

The majority of Lesotho is characterised by high altitude mountainous areas from the east, north and south with gradient slopes to lower mountainous areas in the west and northwest, whereas the southwest have a lower gradient and undulating midslopes. Historically large mammals such as: plains zebra, black and red were found in the western lowlands of Lesotho (Lynch 1994; Boshoff & Kerley 2013). Whereas species such as eland and were located throughout Lesotho, however there were seasonal movements of these into the low lying areas during the cold winter months (Boshoff & Kerley 2013).

The majority of the records of large mammalian species described below were extracted from: Boshoff & Kerley 2013. Historical Incidence of the Larger Mammals in the Free State Province (South Africa) and Lesotho.

Eland (Tragelaphus oryx)

Recordings and sightings from the early 1810 onwards to 1900 suggest that eland were present in most of Lesotho. The literature also advises numerous times, that the eland utilized the high mountainous areas in the summer months when the climate was warmer and moved down to

7 lower to escape the snow and cold in during the winter months and to find better grazing. Since the 1900s and to date there have only been a few eland records in Lesotho and these animals were recorded along the borders of Lesotho were conservation areas have been established in KwaZulu-Natal Province of South Africa. Sightings of eland in Sehlabathebe National Park are frequent as it is believed that the eland move up and down along the escarpment between South Africa and Lesotho. Eland were a good source of food in the early days and literature has suggested that the eland were hunted out in Lesotho by both locals and travellers in the late 1800s.

Zebra (Equus quagga & Equus zebra zebra)

Historically no Cape mountain zebra occurred in Lesotho. The Cape mountain zebra’s historical range does not overlap with the plains zebra and this subspecies is endemic to South Africa’s fynbos, grassland and karroo habitats found in the Western and provinces (Hrabar et al. 2016). Early records show that the plains zebra occurred in the western lowlands of Lesotho and that this subspecies was last recorded in Lesotho in the 1830s.

Grey Rhebok (Pelea )

The grey rhebok are easily misidentified with mountain in early literature. According to the literature grey rhebok are common throughout most of Lesotho. Records suggested these animals occurred over the full altitudinal range of the mountains. This species is sensitive to human disturbance. Habitat preference of grey rhebok are mountainous slopes with grass cover. (Redunca fulvorufula) coexist with the grey rhebok, however they prefer a more flat long grass habitat.

Black Wildebeest (Connochaetes gnu)

Historically occurred in suitable habitat of flat and gently undulating terrain which included the lowlands and wide-bottomed river valleys of Lesotho. This species did not occur in the highlands of the Maloti-Drakensberg, but occurred within an altitudinal range of between 1000 and 2600masl in the Drakensberg range as a seasonal migrant to the higher areas.

Red Hartebeest (Alcelaphus buselaphus)

The last known records of in Lesotho were individuals that were killed by severe weather in 1918. The persistence of the red hartebeest in Lesotho was attributed to the conservation areas in the Drakensberg in the neighbouring KwaZulu-Natal Province of South Africa. Records suggest these animals occurred over the full altitudinal range of the mountains, however at a low density, in Lesotho. They were also known to migrate to lower lying areas to escape the cold during the winter months.

Springbok (Antidcorcus marsupialis)

Historically there is evidence that occurred in the lowlands of Lesotho, where suitable habitat would have been present, however it is highly unlikely that this species occurred in the Drakensberg Grasslands of the Lesotho Highlands.

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2.6 Park size and available habitat

Ts’ehlanyane NP is 5392ha in total with an area of approximately 426ha fenced with standard 1.4m game fencing (Figure 6). In South Africa the legal requirements for eland fencing is 2.4 metres. The current herd of eland are therefore found within the 426ha game camp (Figure 6). This 10km perimeter fence enclosing the current herd of eland is not large enough to allow genetic diversification and this may result in inbreeding between individuals. Due to the small area of foraging habitat within the perimeter fence, fighting between territorial bulls will be common as the population grows. Displaced bulls may break out of the perimeter fence and become a threat to both human life and farming communities surrounding TNP.

The small size of the game camp is a limiting factor for the long term sustainability of any wildlife species introductions, as intensive management will need to be applied to ensure the survival of these species. Furthermore, the game camp comprises rugged mountainous terrain with very limited low-lying areas which is needed by the game species during the harsh winter months and during cold spells that are often experienced throughout the year. Eland have died in the past due to the harsh winters as they would naturally migrate down to the low-lying areas to avoid the snow in the high-lying areas. Therefore if the low-lying areas are limited as is currently found in the game camp more losses can be expected as the eland population increases in numbers thus decreasing the amount of suitable habitat available for this species.

Figure 6: Ts’ehlanyane National Park, highlighting the game camp found within the north-western section of the park.

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3. DISCUSSION AND RECOMMENDATIONS

The following challenges were identified during the field assessment in TNP and recommendations for each challenge are given:

 Fence maintenance: the game camp perimeter fence is overgrown by vegetation and needs to be cleared to ensure effective implementation of weekly patrols. Furthermore, clearing of the vegetation on the fence will prevent fire damage to the fence. Chemical clearing should not be considered as there will be negative impacts on soil, vegetation and contamination of water through infiltration and runoff.  Limited area available for wildlife (fenced enclosure): the game camp is only 426ha of very mountainous habitat which is too small for sustainable numbers.  Absence of fire management plan: a fire management plan needs to be compiled and implemented for TNP. Fire should be used as a management tool to maintain the representative vegetation types within the park. Due to infrequent fire in the area and lack of grazing by wildlife, there is a clear encroachment of Leucosidea sericea in the Lesotho Highland Basalt Grassland vegetation type. Due to high accumulation of biomass over the years, unpalatable grasses such as Hyparrhenia hirta, Cymbopogon excavatus and Themeda triandra dominate in the landscape. Implementation of block burning in different management units will also assist in manipulating wildlife temporal and spatial usage across the entire landscape.  Lack of game management plan: a game management plan needs to be compiled describing daily monitoring activities.  Lack of staff capacity: insufficient number of staff to ensure fire management, fence maintenance and monthly wildlife monitoring.  Growth of current eland population: there has been a slow population growth of eland since introduction in 2008, with a current population of about 28 animals in 2017, from an initial introduction of 25 animals – insufficient data to work out recruitment rate of this population.  Size of game camp: a bigger area is required as fighting for territory has been observed in the current eland herd, with one bull being chased out of the herd and two killed during territorial conflict. Furthermore, 6-10 eland died during the winter months due to harsh weather conditions. The steep terrain within the game camp might have resulted in some physiological challenges with possible reduction in reproduction rate of the eland. It is recommended that the entire park is fenced before any other game is introduced.  Future reintroductions: a bigger area is required to allow habitat range for more than one herd of eland and other species intended for introduction. Focus for future introductions should be on species that historically occurred in the area (see section 2.1.5) and are able to adapt to the harsh winter conditions.  Objectives for introductions: IUCN guidelines should be revisited and the objectives for introduction should be set according to these guidelines. The objectives should be clear for population restoration (i.e. reinforcement or reintroduction of species within their indigenous range) or ecological replacement (i.e. to perform an ecological function lost by extinction of an original form) (IUCN/SSC 2013)

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 Habitat management: Implementation of management units and monitoring will be required before any introduction may be considered (see suggested management units below). The current fenced area is also not large enough to allow growth within the current population.

3.1 Management Units

It is recommended that the park be divided into four management units (Figure 7) to maintain the ecological functionality (structure, function and composition) of the park. In managing fire within each unit; intensity, frequency, season and type of fire will determine the desired state aimed for depending on the management objectives of the park. It is therefore important that fire management be developed to address temporal and spatial use of wildlife and also to maintain representative plant diversity within the entire park.

Figure 7: Proposed Management Units (1 – 4) showing different plant communities in Ts’ehlanyane National Park

The Leucosidea sericea – Buddleja salviifolia Shrubland within each management unit is dominated by shrubs which provide browsing, though most species are not so palatable. The Leucosidea sericea – Buddleja salviifolia Shrubland is also associated with the drainage lines, providing water in the landscape. Leucosidea sericea may encroach areas outside their natural habitat due to lack of fire in the landscape (i.e. Themeda triandra – Festuca caprina Grassland). Fire in these management units will assist in controlling bush encroachment and will also encourage grass diversity and good habitat for wildlife. The Themeda triandra – Festuca caprina plant community is the most appropriate area for grazing and can be maintained by implementing a fire management plan.

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The narrow strip of Helichrysum trilineatum – Chrysocoma ciliata found on the escarpments of the management units comprises shallow soils with surface rock (outcrops) including some areas with rock rubble. Majority of the Lesotho mires (peatlands) are embedded within the Helichrysum trilineatum – Chrysocoma management units (Mucina & Rutherford, 2006). The grassland of the alpine heathland are only palatable in the limited period between late spring and end of summer (November – March). The high altitude alpine vegetation also has a high proportion of endemic plants and has been identified as a (Cowling & Hilton-Taylor, 1994). Continuous monitoring should therefore be implemented to identify endemic and threatened species and also detect degradation resulting from grazing and soil erosion.

4. CONCLUSION

This report focuses on a habitat assessment of Ts’ehlanyane NP, the historical distribution of large mammals in Lesotho and key issues raised during the field assessment. The eland that were introduced between 2008 and 2009 seem to have adapted to the landscape even though there is a slow growth rate due to several factors discussed above. Consideration can still be made for introduction of other species such as Grey Rhebok once the entire park has been fenced and other management issues have been addressed. No further introduction of eland should be undertaken until the game management area has increased in size, allowing the eland access across the entire park. This will be followed by monitoring to determine if habitat size is one of the factors influencing population growth. Species such as Plains and mountain zebra have no historical record in Lesotho and the steep terrain does not provide suitable habitat for their survival. The same applies for springbok as there is evidence that they historically occurred in the lowlands of Lesotho and will therefore not survive in Ts’ehlanyane NP. It is therefore recommended that future introductions be considered only after all the challenges mentioned in this report have been addressed.

5. ACKNOWLEDGEMENTS

MDTP, Lesotho colleagues and SANParks are thanked for their support during the visit from 30 January to 03 February 2017. Abel Matsapula, SANParks’ Field Assistant (GIS) for creating all the shape files.

6. REFERENCES

Boshoff, A.F. & Kerley, G.I.H. 2013. Historical incidence of the larger mammals in the Free State Province (South Africa) and Lesotho. : Centre for African Conservation Ecology, Nelson Mandela Metropolitan University.

Cowling, R.M. & Hilton-Taylor, C. 1994. Patterns of plant diversity and in : an overview. In: Huntley, B.J. (ed.), Botanical diversity in Southern Africa: 33-54. Strelitzia 1. National Botanic Institute, Pretoria.

Gill, A.M. 1975. Fire and the Australian flora: a review. Australian Forestry 38: 4-25

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Hrabar, H., Birss, C., Peinke, D., King, S., Novellie, P., Kerley, G. & Child M.F. 2016. A conservation assessment of Equus zebra. In Child, M.F., Roxburgh L., Do Linh San, E., Raimondo D., Davies-Mostert, H.T., editors. The Red List of Mammals of South Africa, Swaziland and Lesotho. South African National Biodiversity Institute and Endangered Wildlife Trust, South Africa.

Killick, D.J.B. 1963. An account of the plant ecology of the Cathedral Peak area of the Natal Drakensberg. Botanical Survey Memoir No. 34. Pretoria.

IUCN/SSC. 2013. Guidelines for Reintroduction and Other Conservation Translocations. Version 1.0. Gland, Switzerland: IUCN Species Survival Commission, viii +57 pp.

Le Maitre, D.C. & Midgley, J.J. 1992. Plant reproduction ecology. In Cowling, R.M. (ed.). The ecology of fynbos, nutrients, fire and diversity, pp. 135-174. Oxford University Press,

Lynch, C.D. 1994. The Mammals of Lesotho. Narvorsinge van die Nationale Museum, Bloemfontein 10 (4): 178-241.

Morake P. 2010. Documenting historical faunal change in Lesotho and the adjoining Eastern Free State of Southern Africa. Unpublished MSc Dissertation. University of . , South Africa.

Mucina, L. & Rutherford, M.C. (eds.) 2006. The vegetation of South Africa, Lesotho and Swaziland. Strelitzia 19. South African National Biodiversity Institute, Pretoria

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