Lake Ashenge is in Ofla Woreda of the Southern Zone. The nearest town is Korem, about 120 km south of the regional capital Mekele. The lake and its surrounding area occupy an old volcanic crater between the Ambalagie range to the north and the Alamata mountains to the south. The altitude at the lake is 2,400 m while the mountains to the north rise to over 3,000 m. The lake is fed by a number of small streams from the surrounding areas, and as far as is known there is no drainage out of it. The crater rim forms steep cliffs all around, except in the north-east where there is a long valley. Korem is situated in a long valley to the south. The area surrounding the lake is relatively flat, producing extensive areas of shoreline, and large areas of marshland extend into the valley to the north-east. The lake has a surface area around 14,000 ha, a mean depth of c.14 m and a maximum depth of 25.5 m. The water is slightly saline. Villages are situated on the flatter land at the foot of the cliffs, but all of the surrounding land is used for agriculture. The valley in the north-east is an important grazing area, particularly through the dry season. Land is divided between villages and access to the grazing area is carefully managed. The flora of this area has never been documented. Some trees are found in the area, often confined to domestic gardens, including Acacia shrubs, Croton macrostachyus, Vernonia amygdalina and Buddleja polystachya. Additionally, some forest trees are found around churches and in Muslim graveyards: species include Acacia abyssinica, A. pilispina, Ekbergia capensis, Juniperus procera and Olea europaea cuspidata. Mixed agriculture dominates the area, with cereals and pulses the main crops, and cattle and sheep the main domestic animals. Fish were introduced into the lake, but for unknown reasons the harvest has not been sustainable.
See Box for key species. The lake probably holds 20,000 waterbirds on a regular basis: a total of 17,000+ was recorded in January 1995. At least 30 Aythya nyroca have been recorded. A small number of Afrotropical Highlands biome species occur including the endemic Serinus nigriceps, Columba albitorques, Onychognathus albirostris and Corvus crassirostris. Other interesting species include Bubo capensis and Turdoides tenebrosus, the latter a species of the Sudan–Guinea Savanna biome; see Table 3.
Non-bird biodiversity: None known to BirdLife International.
Pressure/threats to key biodiversity
Lake Ashenge is a closed ecosystem. Recent efforts to increase crop production through the use of high-yielding varieties, which require high doses of fertilizers and pesticides, have targeted Ofla Woreda, as its main crops, maize and wheat, respond well to such a system. The resulting accumulation of chemical residues in the lake could have a serious negative impact on the productivity of this wetland. Thus, appropriate monitoring schemes should be initiated to track the situation closely. A project has recently been started in Tigray Region aimed at encouraging organic farming methods as a means of increasing food production (and reducing the introduction of chemicals to the environment). A village next to Lake Ashenge has joined this project.