This part of the shore of Lake Malawi, between 11°30’ and 12°08’S, some 70 km from north to south, receives more than 2,000 mm of rain annually and was covered, until late in the nineteenth century, with dense lowland rainforest and transition woodland (i.e. miombo with some evergreen species). The region is heavily populated today, and much of the natural vegetation has been turned to cash-crops such as tea and rubber. Only a few small patches of forest have been preserved in reserves, and the site includes the four main ones. These are, from north to south, Kalwe Forest Reserve (80 ha) and Nkuwadzi Forest Reserve (600 ha) near Nkhata Bay, Mzuma Forest Reserve (c.600 ha) near Chintheche and Kuwilwe Hill Forest Reserve (c.200 ha) some 38 km south-west of Chintheche. The sizes given in parentheses are those of the patches of forest and semi-evergreen transition woodland; the Forest Reserves also include more open miombo woodland and trial plots of plantations not considered here. The altitude of the first three reserves named is mainly between 500 m and 650 m; Kuwilwe Hill, an outlier of the South Viphya Plateau, rises prominently to 1,496 m, with forest ascending to 1,200 m in gullies. Floristically, the forests are somewhat impoverished, but represent a unique association of Zambezian elements and others of Guineo–Congolian affinity. They are best-developed at Nkuwadzi and Mzuma, where the 40-m-tall canopy is dominated by Brachystegia microphylla and B. spiciformis (briefly deciduous). Evergreen forest along streams and in depressions is characterized by Afrosersalisia cerasifera, Erythrophleum suaveolens and Sorindeia madagascariensis. The evergreen understorey includes numerous lianas and the ground storey is often a dense and impenetrable thicket of woody creepers.
See Box and Table 3 for key species. Some 112 species have been recorded; the area has been selected particularly for its (still) important population of the isolated Malawi endemic race (bensoni) of Sheppardia gunningi, which reaches densities of 1–2 pairs/ha in optimal habitat, alongside other common robins (Erythropygia quadrivirgata, Cossypha natalensis). The population left in the four reserves may be around 1,500 pairs. It is one of a very few localities in the country where the cuckoo Cercococcyx montanus still occurs, and Guttera pucherani, another highly localized species in Malawi, is recorded from Mzuma and Nkuwadzi. Two species of the Afrotropical Highlands biome occur as winter (non-breeding) visitors, Pogonocichla stellata and Apalis chapini, the latter also of the Tanzania–Malawi mountains EBA (see Table 2 and 3). In addition, two species of the Zambezian biome also occur (see Table 3).
Non-bird biodiversity: Butterflies: Pentila carcassoni and Euphaedra murphyi (if a good taxon) appear to be endemic to these forests. Other species known from nowhere else in Malawi include: Graphium polistratus, Acraea perenna, Oboronia bueronica, Xanthodisca vibius, Acleros placidus, Andronymus helles, A. evander and A. fenestrella. Thirteen species of butterfly reach southern limits: Andronymus helles, A. evander, A. fenestrella, Acleros placidus, Xanthodisca vibius, Euphaedra paradoxa, Catuna sikorana, Bematistes epaea, Acraea perenna, Aphnaeus flavescens, Deudorix camerona, Amauris tartarea and A. crawshayi.
BirdLife International (2020) Important Bird Areas factsheet: Lake-shore Forest Reserves. Downloaded from http://www.birdlife.org on 28/09/2020.