Boland Mountains

Year of compilation: 2001

Site description
The site encompasses a chain of mountains that have been designated as State Forests, Mountain Catchment Areas and Nature Reserves. The IBA runs north from the Kogelberg State Forest (near Betty’s Bay and Kleinmond) for 120 km to the Kluitjieskraal State Forest south-west of Tulbagh. The mesic mountain fynbos is dominated by a multitude of communities; the primary fynbos constituents are species of Proteaceae, Ericaceae and Restionaceae. Small, isolated Afromontane forest patches, in deep secluded mesic gorges, are dominated by trees of Cunonia, Halleria, Pterocelastrus, Rapanea and Podocarpus. Shrubs, ferns, climbers and epiphytes also occur.

Key biodiversity
See Box and Tables 2 and 3 for key species. Within the low fynbos scrub, both Turnix hottentotta and Sarothrura affinis are found. Among the fynbos endemics, Nectarinia violacea is widespread in the ericas while Promerops cafer and Serinus leucopterus are almost restricted to the proteoid elements. Francolinus capensis, Pycnonotus capensis and Serinus totta are widespread, while Bradypterus victorini is locally common within moist seeps in hilly areas. Chaetops frenatus and Geocolaptes olivaceus are common on most exposed rocky slopes above 1,000 m. The isolated forest patches hold some forest specials including Buteo oreophilus and Serinus scotops. The agricultural wheat-growing belt to the south-east supports Grus paradisea, Neotis denhami, Circus maurus, Sagittarius serpentarius and Ciconia ciconia, all of which regularly forage within the agricultural matrix at the base of the mountain ranges.

Non-bird biodiversity: This area is thought to contain c.2,500 plant species, most of which are endemic to the Cape Floral Kingdom, and many have global ranges entirely restricted to the IBA. Within the IBA, the Kogelberg area alone has 150 endemic plant species, and is often considered to be the heart of the Cape Floral Kingdom. Many spectacular species occur in the IBA, including the endemic, critically threatened ‘marsh rose’ Orothamnus zeyheri (Proteaceae). 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. Microbatrachella capensis (EN) 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 Barbus burgi (CR) and B. andrewi (VU). Pseudocordylus nebulosa has a global range restricted to the mountains of this IBA. 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.Australolacerta australis occurs here and at only one other site (IBA ZA080), and Cacosternum capense, Breviceps gibbosus, B. montanus and Afroedura hawequensis have most of their global ranges in this IBA. Western Cape endemics occurring in the Eastern False Bay mountains include Tropidosaura gularis, Pseudocordylus capensis, Afrogecko porphyreus and the spectacular Heleophryne purcelli, Arthroleptella lightfooti and Capensibufo rosei (LR/nt), which are all restricted to perennial streams in forested boulder-strewn gorges in montane areas and shallow, water-filled depressions in montane fynbos. Hyperolius horstockii occurs in the lowlands with flowering lilies.

Pressure/threats to key biodiversity
The IBA consists of a network of many formal and contractual conservation areas. Some fynbos reserves have been established to conserve particular, single species. The proclamation of the Kogelberg State Forest was based on securing the future of the endemic and greatly threatened plant Orothamnus zeyheri. The Kogelberg Nature Reserve (18,000 ha) has since been shown to hold a great number of other localized, threatened and endemic plant species. This reserve, which was transferred from the Department of Forestry to Cape Nature Conservation in 1987, lies on the eastern flank of False Bay and is now managed according to the internationally accepted principles of a Biosphere Reserve, with the bordering agricultural fields and pine plantations of the South African Forestry Company Limited (SAFCOL) forming a buffer zone. This area is continuous with the Highlands and Lebanon State Forests to the east and north respectively. Nuweberg State Forest links Highlands and Lebanon to the Hottentots Holland Nature Reserve (42,000 ha). Farther north the Hawequas and Kluitjieskraal State Forests form the northern portion of this IBA chain. All these protected areas fall within the Hottentots Holland and Hawequas Mountain Catchment Areas, which also hold substantial proportions of privately owned land.

Invasive non-native trees of Acacia, Hakea and Pinus pose a serious threat to both vegetation and water conservation in these mountains. Locally, these exotic taxa can dominate thousands of hectares, significantly modifying soil composition, fire regime and natural plant and animal communities, threatening many indigenous species with extinction. Alien trees are also known to accelerate riverbank erosion and reduce in-stream flow through excessive transpiration. The control of invasive alien taxa is the single largest task facing most managers in this biome. Bio-control agents, including fungus and insects, have been introduced to prevent the spread of alien species; some of these agents have been extremely successful. The ‘Working for Water’ programme, initiated by DWAF, involves physical removal of alien plants in water catchment areas. This ingenious programme increases water run-off and simultaneously employs people.

This IBA is close to Cape Town and it is surrounded by intensively farmed areas (for wheat and wine), towns and hamlets. The mountain chain is used extensively for hiking and other recreational purposes. The greater human usage of this mountain range increases the chance of dispersal of the non-native Argentine ant Iridomyrmex humilis into these ecosystems. This ant ousts the indigenous ant species that disperse the seeds of numerous fynbos plants; the loss of the indigenous ant species could have a major negative impact on the local biota.

Recommended citation
BirdLife International (2022) Important Bird Areas factsheet: Boland Mountains. Downloaded from on 14/08/2022.