Located 5 km west of Port Edward, Umtamvuna Nature Reserve occupies the eastern side of a steep gorge on the Umtamvuna river. The river gorge meanders through the reserve for 25 km before it enters the Indian Ocean, 2 km beyond the reserve boundary. Many precipitous side-streams join the river within the reserve. The river is flanked by evergreen forests, overtopped with up to 240 m of often sheer cliffs of Pondoland sandstone. Above the cliffs, on either side, are gently undulating sandy grassy plains, with scattered and little eroded rocky outcrops. There are many seepages and small vleis.The vegetation is Pondoland coastal plateau sourveld, and consists of forest and grassland, each vegetation-type occupying c.1,500 ha. The forest boasts over 330 woody species. It has typical coastal elements, together with species usually associated with the mistbelt, but many of the dominant trees are near-endemics. Common canopy trees include Celtis, Harpephyllum, Ficus, Pseudoscolopia, Cassipourea, Rhus, Oricia, Vepris and Cryptocarya. Cliff-edges and fire-protected rocky outcrops have dense clumps of Schefflera, Brachylaena, Cassine, Protorhus, Diospyros, Cryptocarya and Rhus. The grassland is also exceptionally diverse and only a third of its species are grasses, the remainder being sedges and forbs.
See Box and Tables 2 and 3 for key species. The extensive series of cliffs in the Umtamvuna Gorge hold one of the only coastal colonies of Gyps coprotheres in South Africa. The colony is thriving, and is one of the few in South Africa that is not declining. Typically 20–30 chicks fledge each year. The viewing opportunities, for seeing the vultures at their nests, and cruising around the breeding cliffs, without causing any disturbance, are without parallel in South Africa. The reserve holds a vulture restaurant, where carcasses are provided, without any particular timetable, in order to encourage the vultures to forage near home. The grasslands hold species of conservation concern such as Grus paradisea, Neotis denhami and Circus maurus. The wetlands in the reserve hold Balearica regulorum. The backwaters of the river hold Podica senegalensis. The forest in the gorge supports a small population of Zoothera guttata (in winter), as well as Tauraco corythaix, Campethera notata, Cossypha dichroa, Cercotrichas signata and Serinus scotops.
Non-bird biodiversity: Umtamvuna is an ancient centre of botanical endemism, and is the finest remaining example of the highly diverse Pondoland sandstone flora. Some of the plants are extremely rare and localized. Raspalia trigyna, for example, was at one time thought to be represented by only a single individual plant. This was killed in an accidental fire. Subsequently, the species has been reintroduced, using cuttings from a second plant recently discovered in the former Transkei. The forest is the only, or principal, home of a host of rare trees. Examples are Catha abbottii, Ochna chilversii, Colubrina nicholsonii (EN), Manilkara nicholsonii (EN), Pseudosalacia streyi (VU), Eugenia umtamvunensis (VU), E. verdoorniae (LR/nt), at least three other species of Eugenia awaiting description, Dahlgrenodendron natalensis (EN), Syzygium pondoense (VU), Indigofera braamtonyi, Maytenus abbottii (VU) and M. bachmannii.
Rare grassland plants include Rhus pondoensis, Leucadendron spissifolium, Encephalartos laevifolius, Raspalia trigyna, Podalyria velutina, Psoralea abbottii, Phyllanthus arvensis, Anisodontea scabrosa, Erica abbottii, Brachystelma australe, Selago peduncularis and Helichrysum diffusum. Rock outcrops bear Anthospermum streyi, Apodytes abbottii, Craterostigma nanum, Canthium suberosum and C. vanwykii. The chameleon Bradypodion caffrum, a Pondoland coastal plateau endemic, is present, as are the butterflies Charaxes pondoensis and Durbania amakosa albescens.
Pressure/threats to key biodiversity
Umtamvuna was owned from 1939 onwards by the Forestry Department, with the original intention of planting timber. However, the land was absolutely unsuitable for this purpose, never developed, and was given to the KwaZulu-Natal Nature Conservation Service (formerly the Natal Parks Board) to be proclaimed a Nature Reserve in 1971. The reserve was enlarged in 1983. During the 1980s two threats loomed, both of which seem to have receded. The first was a proposal to dam the river downstream of the reserve, to boost the water supply for Port Edward. The dammed water would have backed up into the reserve, inundating the adjacent riverine vegetation. The second was a plan to mine bauxite in the catchment upstream of the reserve. There can be little doubt that severe contamination of the river would have resulted.