The Jemma and Jara are permanent rivers that flow through Northern Shewa Zone down from Were Illu, through Merhabete and then as the Jemma river into a large gorge beside Debre Libanos and Fiche. The Jemma joins the Wenchit before reaching the Abbay (Blue Nile) (site ET016). By road and track the area is c.180 km north of Addis Ababa. The Jemma and Jara rivers are mainly difficult of access, at the bottom of steep-sided gorges that have been cut through basalt to expose the underlying large blocks of limestone and sandstone. The bottoms the valleys comprise gently sloping land, and the rivers have created gravel flood-plains of varying width. The altitude at the Jemma river-crossing is 1,300 m, and 2,000 m at the top of the gorge. Habitats comprise: the rivers, which are fairly fast-flowing; Typha spp. beds beside the permanent rivers; blocks of limestone that support Sterculia africana trees, Tamarindus indica and Ficus thonningii; the endemic Aloe schelpii; and acacia woodland away from the rivers and on the sides of the gorge. The sides of the gorge support extensive areas of grassland. Acacia woodland, the dominant vegetation in this area, is both denser and more extensive in the Jara than in the Jemma valley. There are small to medium-sized trees of Acacia seyal, Commiphora spp., Ziziphus spina-christi, Combretum spp., Terminalia brownii, Grewia bicolor and other Grewia spp., Balanites aegyptica and Maytenus spp. There are some large figs and larger trees of Cordia africana and Syzygium guineense by the river as well as on the sloping areas at the base of the cliffs. There is no well-developed riverine forest. Much of the valley bottom and sloping sides are cultivated with sorghum and sesame. Tef Eragrostis tef becomes increasingly common with altitude. The extent of cultivation is relatively smaller in Afer Bayene and Jara than in Jemma valley, where 80% of the area surveyed was cultivated. After the rainy season, when the water-level has dropped, farmers burn off the bulrushes and plant additional sorghum and some cotton in the moist black soil.
See Box and Tables 2 and 3 for key species. A survey in May 1996 found Francolinus harwoodi to be (apparently) more widely distributed in the Jemma valley and adjacent river systems of North Shewa Zone than was previously thought, and the species may well extend into Were Ilo, South Wello Zone; it is abundant in at least some parts of its range, with sizeable populations recorded at Jara valley (1,450–1,500 m) and Afer Bayene (1,800 m); until recently it was believed that beds of Typha spp. provided crucial habitat for it, but recent observations suggest this is not so. A small population of the restricted-range Myrmecocichla melaena is present on the precipitous, rocky escarpment sides. This area supports an interesting cross-section of biome-restricted species, including those listed below and six Somali–Masai biome species. Birds of particular interest, whose distributions extend along lowland river systems far into the highland massif, include various species normally considered restricted to the lower lands to the west of the rift, namely Streptopelia vinacea, Cisticola troglodytes, Sporopipes frontalis, Lamprotornis chloropterus and Lagonosticta larvata. Additionally, Ptilopachus petrosus frequents the rocky slopes, Onychognathus albirostris is fairly common on the cliffs of the escarpment and Serinus xanthopygius can also be found in the area.
Non-bird biodiversity: None known to BirdLife International.
BirdLife International (2020) Important Bird Areas factsheet: Jemma and Jara valleys. Downloaded from http://www.birdlife.org on 07/08/2020.