The Dawa river and Wachile plains are in southern Borena Zone. A bridge crosses the Dawa river on the Negele–Arero road, 50 km from Wachile. Wachile village is a natural meeting place for traders and travellers in the area with Mega, Moyale, Arero and Negele all within 150 km. The topography of the site is a combination of very flat plains, river valley and some hills. The Dawa river is the largest tributary of the Genale river and forms part of the Genale–Dawa basin. It drains nearly a third of Genale’s 168,000 km² basin area and has a total length of 450 km. The flow of the river, like the rains over the catchment, is highly seasonal. The Dawa river starts as the Mormora and Awata rivers that flow down the eastern slopes of the Sidamo mountains (that support the Anferara forests, site ET058) between Dila and Bore. The Dawa river then loops round in a south-easterly direction until it joins the Ethiopia–Kenya border near Melka Mure and continues east along the border for 150 km until joining the Genale river at Dolo on the Ethiopia–Somalia border. A number of seasonal rivers and streams feed into the Dawa. The largest trees in the riverine forest along this lower section of the Dawa river are Diospyros mespliformis, Ficus sycamorus, Mimusops kummel, Tamarindus indica and African mahogany Trichilia emetica. Shrubs of Ficus capreaefolia cover much of the bank, and there are reedbeds in the river. The Wachile plain is mostly covered with bushland and thickets. Most of the species remain bare during the long dry season making evergreen species such as Acokanthera schimperi, Dobera glabra, Euclea racemosaschimperi and Salvadora persica highly conspicuous. The more numerous deciduous species primarily comprise Acacia spp., Commiphora spp., Boswellia microphylla and B. neglecta. Some trees emerge above these bushes. Species of particular interest in this area are Delonix elata, Kirkia tenuifolia, Melia volkensii and Terminalia orbicularis, with Terminalia polycarpa on the rocky slopes. The whole area is too dry for crops to grow, and consequently the Borena people have formed a highly developed pastoralist society. There are many small ponds built by the local people to provide water over a wide area for their animals. They also have very deep hand-dug wells that tap underground water. The other important economic activity throughout the dry southern parts of Borena is the collection of gums and resins, particularly from trees of Commiphora and Boswellia.
See Box and Tables 2 and 3 for key species. This area is important for Streptopelia reichenowi, which is found along the Dawa river, particularly to the north of the bridge, where more than 30 have been recorded in stands of riverine trees. Ploceus dichrocephalus is found in the same area as S. reichenowi, breeding in the reedbeds along the Dawa river. So far, 45 Somali–Masai biome species are known from the site. During a survey in June 1996, Tmetothylacus tenellus, Dryoscopus pringlii, Laniarius ruficeps, Turdus tephronotus, Cisticola nanus, Batis perkeo, Nectarinia hunteri and Nectarinia nectarinioides were all found in the arid Acacia bush and scrub habitats of the Wachile plains. A yet-to-be-identified species of babbler has been found in the riverine thicket below the Dawa river bridge.
Non-bird biodiversity: None known to BirdLife International.
Pressure/threats to key biodiversity
No conservation efforts have been noted in this area. The Borena breeds of cattle and sheep are highly prized, both nationally and as export products. The vegetation has been managed in a sustainable fashion (i.e. without overgrazing) for a long time by the Borena pastoralists, but development programmes that were designed and implemented without any real understanding of Borena society and its traditional management practices have to some extent created the problems now faced by these people and this area (such as overgrazing, inappropriate irrigation initiatives and gold mining). Any attempts to introduce irrigated agriculture using the very variable flow of the Dawa river or groundwater could have very marked negative effects on the ecological balance in the area. Panning for gold, which is being conducted intensively along the banks of Dawa river, is a significant potential threat to the river and its associated flora and fauna.