The National Park occupies the mountainous bulge that protrudes into Lake Tanganyika along its eastern shoreline. The mainly grass-covered mountain ridge that runs parallel to the lake is forested in parts with rich gallery forest extending down the many watercourses. Some of these forested valleys have extensive stands of bamboo. The lower slopes are cloaked in tall Brachystegia woodland which dominates the western and drier eastern areas. The south-western and southern tip of the peninsular are dominated by smaller Brachystegia woodland.
See Box and Tables 2 and 3 for key species. The area is relatively poorly known ornithologically. A draft species list includes only 214 species, reflecting a paucity of fieldwork rather than low species-richness. These include three Guinea–Congo Forests biome species (see Table 3). There is some evidence that this site has ornithological affinities with the highlands of the Albertine Rift rather than the Ufipa plateau in south-western Tanzania. An endemic subspecies of the globally threatened Apalis argentea is present at the site. Endemic subspecies of Phyllastrephus flavostriatus, Andropadus tephrolaemus, Platysteira concreta, Alethe poliocephala, Sheppardia bocagei and Phylloscopus ruficapilla, and an endemic race of Nectarinia regia also occur. A new subspecies of Anthoscopus caroli was described from the site in the 1960s. The highland-forest Poeoptera stuhlmanni is only known in Tanzania from Mahali, as is the enigmatic Bradypterus alfredi.
Non-bird biodiversity: The park was created to protect a large population of Pan trogolodytes (EN).
Pressure/threats to key biodiversity
This is one of the few protected areas in Tanzania that is not under pressure from agricultural encroachment along its borders. The extensive woodlands and forested river valleys to the east of the park are virtually uninhabited. While the habitat to the east of the park still has a low human density, it would be opportune to extend the park eastwards to include the potentially important water catchment of the Mwesi and Sitwe Hills, with their forested valleys. This would protect further habitat for Pan trogolodytes and known populations of Apalis argentea. It could also be used to increase tourism in the area by providing a road link between Mahali and Katavi National Park (TZ002).
BirdLife International (2022) Important Bird Areas factsheet: Mahali Mountain National Park. Downloaded from
http://www.birdlife.org on 05/10/2022.