The Nyanga mountains form the northernmost extent of the Eastern Highlands in Zimbabwe. They lie about 70 km north-east of Mutare in two rural Districts, Nyanga and Mutasa. The mountains are a popular tourist destination, attracting large numbers of visitors. Nyanga National Park (440 km²) forms the core of this site and also part of an adjacent, contiguous IBA, Nyanga lowlands/Honde valley (IBA ZW002). The park is surrounded by privately owned commercial farms, forestry plantations, tea estates and communal lands.The Nyangani massif peaks at 2,592 m. The topography is very diverse, with a rolling hilly plateau in the west and north giving rise to several large rivers: the Kairezi, Nyangombe and Pungwe. The plateau is deeply bisected by the gorges of the Pungwe and Nyazengu rivers in the south. There are numerous high waterfalls, with the Mutarazi waterfall being one of the highest in Africa, dropping 380 m. The eastern slopes of the mountains, particularly Nyangani mountain, form a steep-sided escarpment, dropping down to 900 m into the Honde valley. The west side has an escarpment that drops from Rukotso (2,405 m) and World’s View to the Nyanga North Communal Land (1,400 m).The eastern slopes are often covered in mist. Above 1,800 m the temperatures are cool and relatively temperate. Frost (4°C) is common in winter. The mountains have extensive Afromontane vegetation at high altitude (1,800–2,400 m), comprising fine-leaved dwarf shrubland with a large variety of herbaceous plants, including some Afro-alpine species. Afromontane rainforests are found on the eastern (windward) slopes (the IBA is defined as extending down to the 1,650 m contour, the boundary of the montane forest) and in kloofs on the leeward slopes. Syzygium is dominant in this undisturbed forest. Afrocrania montane forest occurs on wet boulder-screes and in high valleys. These forests have affinities with those further north in Malawi and East Africa. There are small patches of drier Widdringtonia coniferous forest in fire-protected sites. In the drier, flatter west, the grasslands are interspersed with dwarf Brachystegia woodland. Acacia woodlands occur in isolated patches at the base of granite kopjes. There are also extensive plantations and forests of non-native Acacia and Pinus throughout the area. Fire is an important ecological factor, particularly in the grassland environment.
See Box and Tables 2 and 3 for key species. Because of its accessibility and popularity with tourists, the Nyanga avifauna is relatively well known and includes 246 species. With respect to the species of global conservation concern, Nyanga’s grasslands are an important breeding ground for Hirundo atrocaerulea. An unpublished field survey in Nyanga National Park estimated the population to be at least 400 birds. Since there are areas of suitable habitat outside the park, the total population could be at least 600 birds. Grus carunculatus (four pairs) breed in the national park and adjacent farms. Circus macrourus is an occasional visitor, and Falco fasciinucha, although seen rarely, may breed in the area. Nyanga is a breeding area for two restricted-range species, Apalis chirindensis and Prinia robertsi.
Non-bird biodiversity: The extensive grasslands contain many herbs and shrubs with restricted/localized distributions. There are five or six endemic plants and a further six species with very localized distributions: Aloe inyangensis, Moraea inyangani, Erica simii, Scadoxus pole-evansii, Aloe rhodesiana, Dierama inyangensis, Euphorbia citrina, E. crebifolia and Protea inyangensis. The unusual grassland species are linked to the northernmost limits of the Drakensberg flora. There are several endemic or restricted-range species of amphibian: Bufo gariepensis inyangae, Probreviceps rhodesianus, Arthroleptis xenodactyliodes, Leptopelis flavomaculatus, Afrixalus fornasinii and Hyperolius tuberilinguis. The snake Bitis atropos occurs in the montane grasslands.
Pressure/threats to key biodiversity
Much of the grassland and high-altitude forest is contained within the Nyanga National Park. The single most important environmental threat to the Nyanga grasslands, both inside and outside the national park, is invasion by alien wattle and pine. An unpublished survey in 1988 showed that 40% of the national park had been invaded by alien trees, largely unchecked by Parks authorities, and the situation has worsened since then. At present, commercial forestry companies, national parks and the general public do not recognize the extent and severity of the problem. The avifauna and other species are adversely affected as the highly diverse grasslands change into mono-specific, sterile thickets. Wattle and pine change the soil nutrients and pH and cause a decrease in groundwater. The bird under greatest threat is Hirundo atrocaerulea.High-altitude grasslands outside the park, such as Rukotso, World’s View, Kwaraguza, Bende Gap, Nyafaru and Chingamwe, are included in the IBA, but their present low conservation status needs to be improved. A clear policy and action on the removal of invasive alien plants from these grasslands, inside and outside the national park, is urgently needed.
BirdLife International (2021) Important Bird Areas factsheet: Nyanga mountains. Downloaded from
http://www.birdlife.org on 15/04/2021.