Boland Mountains

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General Information

Status:

Global IBA (A1, A2, A3)

Province:

Western Cape

Protection:

Partially Protected

Size:

170 500 ha

Number:

SA107

Additional Info

  • Site description

    The Boland Mountains IBA (previously the Eastern False Bay Mountains IBA) covers c. 250 000 ha and is located at the western extremity of the Cape fold belt, where much of the complex fold range is forced northwards. The folding process has forged several large peaks and plateaus in this area. The IBA encompasses a continuous chain of mountains and includes several State forests, mountain catchment areas and provincial nature reserves. It runs north from the Kogelberg Nature Reserve (near Betty's Bay and Kleinmond) for 120 km to the Kluitjieskraal State Forest and Waterval Nature Reserve south-west of Tulbagh. The mountains consist of mainly Table Mountain Sandstone sediments. The complexity of folding has led to the formation of many different mountain ranges within the IBA, notably the Kogelberg, Hottents Holland and Limietberg. The area can be divided into four main sections: Kogelberg Nature Reserve, which forms a part of the larger Kogelberg Biosphere Reserve; Hottentots Holland Nature Reserve and Hawequas State Forest; Limietberg Nature Reserve; and Kluitjieskraal State Forest and Waterval Nature Reserve.

    The mountains in Kogelberg Nature Reserve rise sharply from sea level to form peaks such as Voorberg (862 m a.s.l.), which lies only 4 km inland, and the resulting coastline is dramatic. The catchments of the Palmiet and Bot rivers lie within these mountains and the estuary of the latter forms part of the Cape Whale Coast IBA (SA118). The Hottentots Holland range lies in the south of the IBA, above the towns of Somerset West, Stellenbosch and Franschhoek. The slopes of the Stellenbosch, Jonkershoek and Groot Drakenstein ranges are steep and rise rapidly to form Drakenstein Peak (1 491 m a.s.l.), the Twins (1 494 m a.s.l.) and Sneeukop (1 590 m a.s.l.), the highest peak in this region. To the east, the Franschhoek Mountains run over into the southern portion of the extensive Hawequas State Forest, which also holds the Klein Drakenstein, Wemmershoek and Du Toit's ranges to the north-east of Franschhoek. Wemmershoek Peak (1 748 m a.s.l.), Klein Tafelberg (1 821 m a.s.l.) and the tallest peak in the IBA, Du Toit's Peak (1 995 m a.s.l.), with its spectacular pass, are characteristic of the Franschhoek Mountains. The catchments in this area contribute to the Wemmershoek and Theewaterskloof dams.

    Further north, the IBA includes Limietberg Nature Reserve, which encompasses the Limiet and northern Slanghoek ranges and the associated Limietkop (1 152 m a.s.l.) and Bailey's Peak (1 517 m a.s.l.). The topography of the whole Limietberg region is rugged and highly variable, carved by the Wit, Elandspad, Molenaars and Smalblaar rivers and their tributaries, which have created steep cliffs, gorges and deeply incised valleys. In the Elandskloof and Waterval ranges west of Wolseley, Kluitjieskraal State Forest and Waterval Nature Reserve form the northern section of the IBA, with the Voelvlei Dam lying to the west of the Waterval range. These ranges are smaller and less rugged than their southern counterparts, and they fade into rolling hills at their northern extremity. Numerous streams drain these mountains and supply water for agriculture in the Swartland District.

    In winter, prevailing north-westerly and south-westerly winds bring rain associated with sub-Antarctic cold fronts. Although micro-climates significantly affect local rainfall, in general the lower slopes receive c. 800 mm p.a. while the upper slopes and high peaks receive c. 3 300 mm p.a. The region suffers from summer drought where the heat, evaporation and lack of rain can be extreme. Temperatures are moderate and range between -5 °C minimum in winter and 35 °C maximum in summer. The annual average minimum and maximum temperatures are 11 °C and 24 °C respectively. The mesic mountain fynbos is dominated by a multitude of communities, with Proteaceae, Ericaceae and Restionaceae as the primary fynbos constituents.

    Birds

    A total of 274 bird species has been recorded in the IBA during SABAP2. Typical fynbos habitat in the Boland Mountains supports all the Cape Fynbos EBA restricted-range and biome-restricted assemblage species. The forest patches are home to several South African Forest EBA restricted-range species, while within the low fynbos scrub Hottentot Buttonquail Turnix hottentottus and Striped Flufftail Sarothrura affinis are found. Among the fynbos endemics, Orange-breasted Sunbird Anthobaphes violacea is widespread in stands of ericas, and Cape Sugarbird Promerops cafer and Protea Seedeater Crithagra leucoptera are almost restricted to the proteoid elements. Cape Spurfowl Pternistis capensis, Cape Bulbul Pycnonotus capensis and Cape Siskin Crithagra totta are widespread, while Victorin’s Warbler Cryptillas victorini is locally common in moist seeps in hilly areas.

    Cape Rockjumper Chaetops frenatus and Ground Woodpecker Geocolaptes olivaceus are common on most exposed rocky slopes above 1 000 m a.s.l. The mountain peaks and associated cliffs hold a few Black Stork Ciconia nigra, Booted Eagle Hieraaetus pennatus, Verreauxs’ Eagle Aquila verreauxii, Cape Eagle-Owl Bubo capensis and Peregrine Falcon Falco peregrinus. Martial Eagle Polemaetus bellicosus is a rare and widespread resident. The isolated forest patches hold some forest endemics, including Forest Buzzard Buteo trizonatus and Forest Canary Crithagra scotops. The agricultural areas and foothills of the mountains support Blue Crane Anthropoides paradiseus, Denham’s Bustard Neotis denhami, Black Harrier Circus maurus, Secretarybird Sagittarius serpentarius, White Stork Ciconia ciconia and Southern Black Korhaan Afrotis afra, all of which regularly forage within the agricultural matrix at the base of the mountain ranges.

    Voelvlei Dam provides habitat for a range of waterbirds, which congregate in high numbers at this site. It is particularly important for the near-endemic South African Shelduck Tadorna cana, large flocks of which use the site as a safe refuge for their annual post-breeding moult. A total of 1 400 Shelduck has been recorded in a single count, which represents c. 3% of the species' global population. These birds probably move in from the Swartland farmland to the west and north and from the Karoo to the east to undergo their moult at the dam. Voelvlei also provides habitat for large numbers of non-threatened waterbirds such as Egyptian Goose Alopochen aegyptiaca, Spur-winged Goose Plectropterus gambensis and Red-knobbed Coot Fulica cristata

    IBA trigger species

    Globally threatened species are Martial Eagle, Black Harrier, Blue Crane, Denham’s Bustard, Southern Black Korhaan and Hottentot Buttonquail. Regionally threatened species are Verreauxs’ Eagle, African Marsh Harrier Circus ranivorus, Lanner Falcon Falco biarmicus, Cape Rockjumper and Striped Flufftail.

    Restricted-range and biome-restricted species that are locally common in the fynbos elements of the IBA include Cape Spurfowl, Cape Bulbul, Cape Sugarbird, Orange-breasted Sunbird, Cape Rockjumper, Cape Siskin and Victorin’s Warbler, while uncommon species include Southern Black Korhaan, Hottentot Buttonquail, Striped Flufftail and Protea Seedeater. Restricted-range and biome-restricted species that are locally common in the forest elements include Forest Buzzard and Swee Waxbill Coccopygia melanotis.

    South African Shelduck (maximum 1 400 individuals) meets the 1% or more congregatory threshold.   

    Other biodiversity

    This area is thought to contain c. 2 500 plant species, most of which are endemic to the Cape Floral Kingdom; many have global ranges restricted entirely to the IBA. The Kogelberg area alone has 150 endemic plant species and is often considered to be the heart of the Cape Floral Kingdom due to its extremely high levels of plant endemism and diversity. Many spectacular species occur in the IBA, including the endemic, critically threatened marsh rose Orothamnus zeyheri. Once on the brink of extinction, it is now known to occur on several inaccessible peaks in the IBA. The endangered Mimetes hottentoticus and M. capitulatus are also found here. The micro frog Microbatrachella capensis occurs in the south.

    The IBA covers a large portion of the catchment of the Berg River and, along with it, supports several of the Western Cape’s endemic fish, including Berg River redfin Barbus burgi and Cape whitefish B. andrewi. Dwarf crag lizard Pseudocordylus nebulosa has a global range restricted to the mountains of this IBA. Montane marsh frog Poyntonia paludicola, described in 1989, is also virtually endemic to this IBA, where it breeds in shallow streams, seepages and marshy areas on upper mountain slopes. Southern rock agama Australolacerta australis occurs here and at only one other site, the Cederberg–Koue Bokkeveld Complex IBA (SA101), while Cape caco Cacosternum capense, Cape rain frog Breviceps gibbosus, Cape mountain rain frog B. montanus and Hawequa flat gecko Afroedura hawequensis have most of their global ranges in this IBA.

    Western Cape endemics occurring in the Eastern False Bay Mountains include Cape mountain lizard Tropidosaura gularis, graceful crag lizard Pseudocordylus capensis and marbled leaf-toed gecko Afrogecko porphyreus. The spectacular Cape ghost frog Heleophryne purcelli, Cape chirping frog Arthroleptella lightfooti and Rose’s toadlet Capensibufo rosei are all restricted to perennial streams in forested, boulder-strewn gorges in mountainous areas and shallow, water-filled depressions in montane fynbos. Arum lily frog Hyperolius horstockii occurs among flowering lilies in the lowlands. The South African endemic clicking stream frog Strongylopus grayi, banded stream frog S. bonaspei, leopard toad Bufo pardalis and sand toad B. angusticeps also occur in this IBA. The globally threatened geometric tortoise Psammobates geometricus may be found in the remaining patches of renosterveld.

    Southern African endemics of more general occurrence include parrot-beaked tortoise Homopus areolatus, angulate tortoise Chersina angulata, black thread snake Leptotyphlops nigricans, spotted harlequin snake Homoroselaps lacteus, Sundevall’s shovel-snout Prosymna sundevallii, cross-marked grass snake Psammophis crucifer, Cape cobra Naja nivea, many-spotted snake Amplorhinus multimaculatus, berg adder Bitis atropos, Cape legless skink Acontias meleagris, red-sided skink Mabuya homalocephala, spotted sand lizard Pedioplanis lineoocellata, common mountain lizard Tropidosaura montana, Cape girdled lizard Cordylus cordylus, Cape crag lizard Pseudocordylus microlepidotus, southern rock agama Agama atra, ocellated thick-toed gecko Pachydactylus geitje and Cape grysbok Raphicerus melanotis. Threatened mammals include leopard Panthera pardus, aardwolf Proteles cristatus and Cape spiny mouse Acomys subspinosus.

    Conservation issues

    Threats

    The Boland Mountains IBA contains a mixture of protected areas and adjacent agricultural land and includes the Kogelberg, Hottentots Holland, Limietberg and Waterval nature reserves. This system of nature reserves is managed as the Boland Mountains Reserve Complex by CapeNature, which takes a landscape-scale approach to management by prioritising threats and mitigating actions across the different reserves. The majority of threats occur in the buffer zones of the protected areas and, depending on where the IBA boundary extends over a protected area boundary, they will impact on the habitat and bird species. Buffer zone issues are considered to be the most prominent threats to the ecological health of the Boland mountain system.

    The most critical threat facing the biodiversity of this IBA is fire. Fynbos is a fire-maintained ecosystem, and the use of fire as a control agent is now appropriately incorporated into most management plans. Burning operations are prescribed in terms of the three principal components of the fire regime (frequency, season and intensity) and are based on knowledge of the combined effects of these components on the vegetation. Providing the public with greater access to protected areas immensely increases the risk of out-of-season or inappropriate burns by irresponsible or accidental activities. Care should be taken to minimise accidental fires. Factors associated with fire include increases in frequency and intensity and the incorrect season for burning. They lead to fires changing the ecological composition through impacts on the plant communities, with knock-on impacts on the faunal communities. Fynbos-endemic birds, such as Cape Sugarbird, rely on the longer-lived proteas and other plant species, which are the first to be lost from a system when fire frequency and intensity increase.

    Invasive alien plants represent a significant threat in these mountain ranges. Despite large-scale clearing efforts, many of the catchments and privately owned properties still contain high densities of alien plants, which could re-establish in adjacent ‘cleared’ reserves and thus out-compete fynbos vegetation. The fynbos-endemic bird species rely solely on this vegetation for their ecology. Locally, exotic plant taxa can dominate thousands of hectares, significantly modifying soil composition, fire regimes and natural plant and animal communities and threatening many indigenous species with extinction. Alien trees are also known to accelerate riverbank erosion and reduce in-stream flow through excessive transpiration. Many of the freshwater systems in the Western Cape, including the Palmiet, Bot, Wit, Elandspad, Molenaars and Smalblaar rivers, have their source in the Boland Mountains and the high densities of alien vegetation can dramatically reduce the water run-off from their catchments. Currently the Kogelberg Biosphere Area is considered to be at a maintenance stage for alien clearing; Jonkershoek Nature Reserve has issues with invasive alien vegetation in high-altitude sites; and Hottentots Holland Nature Reserve is being prioritised for alien vegetation clearing. The primary species impacting on the reserves are silky hakea Hakea sericea, black wattle Acacia mearnsii, blue gum Eucalyptus species and pine trees Pinus pinaster.

    Habitat transformation due to development is a threat in the areas that do not receive formal conservation protection, notably those outside existing nature reserves and State forests. Conversion into agriculture, namely wine and wheat farming, is the main form of development. The management practices for State forests are largely unknown and their impacts on avifauna must be assessed. The intrusion of agricultural activities onto the borders of the protected areas and within parts of the IBA leads to additional negative impacts, such as pollution of water systems, pesticide drift, soil erosion or illegal entry into the reserves and associated plant harvesting or poaching. However the formal declaration of the protected area components does limit the degree of habitat loss as a result of agricultural expansion. The mountain chain is also used extensively for hiking and other recreational purposes, but these activities in the reserves are well managed by CapeNature and negative impacts, such as disturbance or erosion of trails, are reduced.

    An additional threat may come from wind energy developments planned for the Tulbagh valley to the east of the IBA and around Gouda to the north-west. BirdLife South Africa does not oppose wind energy facilities, but would like to ensure that full pre- and post-construction monitoring takes place at all potential sites to identify potential impacts and mitigate against them. Species at risk include raptors, Blue Crane, and South African Shelduck and other waterbirds utilising the Voelvlei Dam. 

    Conservation action

    The IBA consists of a network of many formal and contractual ‘conservation areas’. The establishment of some fynbos reserves has been based on single-species conservation, such as the proclamation of Kogelberg State Forest to secure the future of the endemic and highly threatened marsh rose Orothamnus zeyheri. Kogelberg Nature Reserve (18 000 ha) has since been shown to hold a great number of other localised, threatened and endemic plant species. The reserve, which was transferred from the Department of Forestry to CapeNature in 1987, lies on the eastern flank of False Bay and is now managed in conjunction with the broader Kogelberg Biosphere Reserve.

    The most effective and important conservation action taken across this IBA is the proclamation of multiple nature reserves managed by CapeNature: Kogelberg, Hottentots Holland, Jonkershoek, Limietberg and Waterval nature reserves. Their designation prevents habitat transformation associated with development and ensures that plans are in place to assist with sound ecological management. CapeNature has developed and continuously updates detailed environmental management plans for the individual nature reserves as well as an overall vision and purpose for the entire Boland Nature Reserve Complex.

    The Boland complex reserves form the IBA and are managed as a single ecological unit. In addition to this complex, there are four smaller reserve complexes in the IBA for which a management plan must be compiled. Two have been completed so far, one is scheduled to be completed by March 2016 and the other by March 2018. Although two reserve complexes do not yet have a management plan, the work done in them is carried out according to an annual ecological plan of operations, which is compiled with input from staff.

    CapeNature has the capacity to manage the Boland Nature Reserve Complex, although certain threats such as fire and the spread of alien vegetation can still severely impact on the ecological health of the IBA. The conservation and management actions being undertaken are comprehensive and include the management of ecosystems and biodiversity, wildlife, fire, invasive and non-invasive alien species, cultural heritage resources, infrastructure, disasters and human resources, as well as law enforcement and the development of a tourism framework. Each of these management categories is subject to relevant legislation, guiding principles and specific management actions as laid out in the Kogelberg Protected Areas Management Plan 2012. All the actions seek to enhance the biodiversity of the IBA while fulfilling recreational needs in the protected areas.

    The remaining land is privately owned and mostly consists of commercial fruit and wine farms. Some of the farms belong to schemes such as WWF-SA’s Fruit and Wine Sustainability Initiative, although membership does not constitute a formal conservation designation. Such conservation initiatives aim to provide environmental management plans at farm level and to drive ecotourism or sustainable landscape management outside the protected areas. Large parts of the IBA are also characterised as mountain catchment areas. The management and legal status of these areas is under consideration by CapeNature. Land transfers between government departments are currently under way and little to no conservation action is being undertaken in the mountain catchment areas.

    The development of the Kogelberg Biosphere Reserve and Cape Winelands Biosphere Reserve is a positive move for conservation in that it ensures that spatial development frameworks and other planning tools for the relevant municipalities take into account the biodiversity and cultural values of these areas. The biosphere reserves have protected areas as their core and are surrounded by buffer zones in which conservation-compatible land use is encouraged and the development needs of the area are provided for.

    An issue with the bird species data available for many of the Cape Fold Mountain IBAs (including Boland Mountains, Cederberg Mountains (SA101), Swartberg (SA106), Langeberg (SA113) and Outenqiua Mountains (SA112)) is the lack of abundance data for IBA trigger bird species. BirdLife South Africa would like to address this gap by initiating monitoring projects with CapeNature ecological coordinators and field rangers. However, the capacity for rangers to undertake such monitoring and for data input varies across IBAs and may not be possible at all sites.

    Related webpages

    http://www.capenature.co.za/reserves.htm?reserve=Limietberg+Nature+Reserve

    http://www.capenature.co.za/reserves.htm?reserve=Hottentots+Holland+Nature+Reserve

    http://www.kogelbergbiospherereserve.co.za/fauna%2B%2526%2Bflora.html

    http://www.capeaction.org.za/index.php?C=land&P=4

    www.capeleopard.org.za

    www.kogelbergbiosphere.org.za

    www.capewinelandsbiosphere.co.za

    Contact

    If you have any information about the IBA, such as a new threat that could impact on it, please send an e-mail to iba@birdlife.org.za or call BirdLife South Africa +27 (11) 789 1122.

    Page last updated

    Wednesday, 28 January 2015

    Further Reading

    Armstrong AJ, Van Hensbergen HJ. 1994. Comparison of avifaunas in Pinus radiata habitats and indigenous riparian habitat at Jonkershoek, Stellenbosch. South African Journal of Wildlife Research 24(3): 48–55.

    Barnes K (ed.). 1998. The Important Bird Areas of southern Africa. Johannesburg: BirdLife South Africa.

    Cowling RM (ed.). 1992. The ecology of fynbos: nutrients, fire and diversity. Cape Town: Oxford University Press.

    Geerts S, Pauw A. 2011. Farming with native bees (Apis mellifera subsp. capensis Esch.) has varied effects on nectar-feeding bird communities in South African fynbos vegetation. Population Ecology 53(2): 333–339.

    Geerts S, Pauw A. 2011. Easy technique for assessing pollination rates in the genus Erica reveals road impact on bird pollination in the Cape fynbos, South Africa. Austral Ecology 36(6): 656–662.

    Johns M, Veldtman A, Cleaver-Christie G. 2012. Kogelberg Nature Reserve Complex Management Plan. CapeNature.

    Le Maitre DC. 1984. Aspects of the structure and phenology of two fynbos communities. MSc thesis, University of Cape Town, South Africa.

    Paterson-Jones C, Manning JC. 2006. Wild Flowers of South Africa. Cape Town: Struik.

    Rabie A. 2005. Biosphere Reserves: The Kogelberg Biosphere Reserve. Stellenbosch Law Review 16(1): 77.

    Richardson DM, Macdonald IAW, Holmes PM, Cowling RM. 1992. Plant and animal invasions. In: Cowling RM (ed.), The ecology of fynbos: nutrients, fire and diversity. Cape Town: Oxford University Press. pp 271–309.

    Van Wilgen BW, Bond WJ, Richardson DM. 1992. Ecosystem management. In: Cowling RM (ed.), The ecology of fynbos: nutrients, fire and diversity. Cape Town: Oxford University Press. pp 345–372.

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