The mistbelt forms an irregular band through the KwaZulu-Natal Midlands, extending from Weza in the south-west to Ngome in the north-east. It once had a large grassland component, but this has now been almost entirely transformed by agriculture and commercial timber. The forest component known as Southern Mistbelt Forest consists of a series of patches occurring mainly on southern slopes where evaporation is less and the effects of fire reduced. Before colonial settlement in the 1800s, these forests were larger and more numerous, and many may have been contiguous. Mistbelt forest represents a southern extension of the Afro-montane forests of tropical Africa. In KwaZulu-Natal most of these forests occur between 1 200 and 1 400 m a.s.l., but may extend as low as 560 m a.s.l. or as high as 1 720 m a.s.l. The climate is temperate and damp. Mists are frequent in summer, as are frosts in winter. Snow falls occasionally. Average rainfall is 950–1 350 mm p.a., falling mostly in summer.
This habitat has as its unifying feature, in the climax stage of succession, the dominance of yellowwood species. Three species, as well as numerous other forest tree species, occur in KwaZulu-Natal. The forest floor has a wealth of small flowering plants supplemented with ferns.
Because of the scattered nature of mistbelt forests, none of which is outstandingly better than the others, it is difficult to single out individual blocks as IBAs. Equally, it is impractical to designate them all, since the total number must run into thousands. The forest patches function in unison as a single ecological unit, and the whole is worth a great deal more than the sum of its parts. The selection criteria adopted for inclusion in this blanket IBA is a minimum size of 50 ha and the presence of the best indicator species of climax forest, Cape Parrot Poicephalus robustus. A total of 32 forest patches, varying in size from 100 to 5 000 ha, are included in the IBA.
The forests hold many important species, including the largest remaining population of the threatened Cape Parrot. Red-necked Spurfowl Pternistis afer and Lemon Dove Aplopelia larvata, both species of the forest edge and forest floor, are common. Bird parties are frequent and typical forest birds include Trumpeter Hornbill Bycanistes bucinator, Crowned Hornbill Tockus alboterminatus, Narina Trogon Apaloderma narina, Orange Ground Thrush Zoothera gurneyi, Bush Blackcap Lioptilus nigricapillus, Knysna Turaco Tauraco corythaix, Olive Woodpecker Dendropicos griseocephalus, Grey Cuckooshrike Coracina caesia, Chorister Robin-Chat Cossypha dichroa, White-starred Robin Pogonocichla stellata, Yellow-throated Woodland Warbler Phylloscopus ruficapilla, Blue-mantled Crested-Flycatcher Trochocercus cyanomelas, Olive Bush-Shrike Chlorophoneus olivaceus, Swee Waxbill Coccopygia melanotis and Forest Canary Crithagra scotops.
Forest predators include Forest Buzzard Buteo trizonatus, Crowned Eagle Stephanoaetus coronatus, Black Sparrowhawk Accipiter melanoleucus and, at night, African Wood Owl Strix woodfordii. The quiet forest river streams hold habitat for Half-collared Kingfisher Alcedo semitorquata and Mountain Wagtail Motacilla clara.
Globally threatened species are Southern Ground-Hornbill Bucorvus leadbeateri, Bush Blackcap and Crowned Eagle. Regionally threatened species are Cape Parrot (a population of 400–600 individuals is estimated), Lanner Falcon Falco biarmicus, Half-collared Kingfisher and Orange Ground Thrush. Biome-restricted and restricted-range species that are commonly encountered include Forest Buzzard, Knysna Turaco, Grey Cuckooshrike, Chorister Robin-Chat, White-starred Robin, Barratt's Warbler Bradypterus barratti, Yellow-throated Woodland Warbler, Olive Bush-Shrike, Swee Waxbill and Forest Canary.
Both tree dassie Dendrohyrax arboreus and blue duiker Philantomba monticola are present. Of the trees, Henkel's yellowwood Podocarpus henkelii is endemic to mistbelt forest and Ocotea bullata is exceptionally rare. Other flowering plants of interest are Geranium natalense and Polystachya ottoniana. Mistbelt forests are very rich in endemic invertebrates, notably spiders, beetles, earthworms, snails and millipedes, many of which are still being described. Of exceptional interest is the presence, only in Ingele Forest, of the onychophoran Opisthopatus roseus or pink velvet worm. This is a member of an ancient relict group, confined to the southern hemisphere, which represents an intermediate evolutionary stage between arthropods and annelids.
Relict mistbelt forests are often located in inaccessible places with steep terrain, making monitoring difficult. Exploitation of these forests began early in colonial history and in some patches continues illegally to this day. Useful tree species, especially Henkel's yellowwood, Ocotea bullata, Ptaeroxylon obliquum and Scolopia zeyheri, were plundered, with lesser use being made of Vepris and Calodendrum species. Ocotea bullata, a good provider of fruits to larger birds, is virtually extinct. Henkel's yellowwood and Scolopia zeyheri, also good fruiters, are localised, although the former is still abundant in places. Old-growth yellowwoods define primary forest, as this slow-growing, shade-tolerant species eventually out-competes other angiosperms and emerges from the forest canopy to dominate.
Recent research shows that the above-ground carbon stock (a measure of forest biomass) in primary forest is 30–40% more than that of secondary forest, and this is due to the dominance of large yellowwoods in the former. Primary forest is very rare in KwaZulu-Natal (only two forest patches in the province can be categorised as such), even though commercial logging has ceased and most patches were last logged between 70 and 150 years ago.
Although forest patches are extremely resilient and have retained much of their plant species diversity, the loss of primary forest has had a severe negative impact on Cape Parrot populations. Cape Parrots rely on yellowwoods (especially Afrocarpus falcatus) for food, nest sites and roost sites. Furthermore, the impacts of the degradation of forest patches and the loss of primary forest on species such as Orange Ground Thrush are not known, but degradation and the associated increase in forest undergrowth are likely to have affected the species.
Even though the threat of commercial logging no longer occurs, certain forest patches are targeted by local communities that cut down large yellowwood trees for use as firewood. A tree is felled and an axe is used to chip away at it to make wood chips, which are then used as fuel while much of the tree goes to waste. Of serious concern is the fact that this is happening in forest patches with formal conservation status, which does not seem to guarantee their protection. It is ironic that the only two examples of primary forest in KwaZulu-Natal fall under private and communal ownership.
Other frequent sources of damage to mistbelt forest are the grazing of cattle in the understorey, which can suppress regeneration, and uncontrolled bark-stripping for use in traditional medicine. Ill-timed grass fires often erode forest margins. Cape Parrots are semi-nomadic and move between the forest patches in response to food abundance. This means that temporarily vacated forests are as important to the integrity of the whole system as those currently in use. Despite their rarity, Cape Parrots are still occasionally taken from the wild for the cage-bird trade. Mistbelt forests play a vital role in altitudinal migration in KwaZulu-Natal. Several bird species from montane forests, or at least a section of their populations, winter in the mistbelt or use the mistbelt forests as corridors on their way to coastal forests.
Protection of mistbelt forest is not strong. About 51% of the total area of the IBA falls under the jurisdiction of DAFF (12 579 ha) and EKZNW (2 924 ha). Most forests, even patches that are formally protected, receive little real protection.
Very little conservation action takes place in this IBA. Each year, with the help of volunteers, the University of KwaZulu-Natal co-ordinates Cape Parrot counts throughout South Africa over a two-day period (one count in the afternoon and another the following morning). The data from these counts provide the best estimate of Cape Parrot numbers in South Africa and indicate the forest patches that are the most important for the species.
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