The site is located around Arero town in the centre of Borena Zone. Arero is about halfway along the track from Negele to Yabello, and 660 km from Addis Ababa. The topography of the area is undulating, with some hills and gorges. Arero forest is the most southerly of the high forests of Ethiopia and is one of the few places in Borena Zone where there are well-grown trees of Juniperus procera. Podocarpus oracilior and J. procera are the largest trees and are found with broadleaved species, e.g. Prunus africana, Teclea nobilis, Croton macrostachyus, Olea capensis, Acacia and figs. This forest also contains several species of small tree characteristic of the Somali–Masai vegetation of Somalia, eastern Kenya and northern Tanzania. Examples are Fagaropsis hildebrandtii and the yellow-flowered Ochna insculpta. In Ethiopia, Ochna insculpta is only known from the Arero forest. Several tall grasses (Andropogon sp., Hyparrhenia spp. and Cymbopogon spp.) grow in the periphery of the forest and in woodland. In 1992 this area comprised 5,437 ha of closed-canopy forest, 2,389 ha of medium-density forest and 2,823 ha of open forest.
See Box and Tables 2 and 3 for key species. Arero forest was previously the most important known site for Tauraco ruspolii (and possibly represents the type-locality), although the species has now been found at Negele, Wadera, Genale and Kibre Mengist. Although forest at this site is being lost, the area still supports a small population, the southernmost in the species’ range, and is believed to be more or less contiguous with that of the Anferera forests (site ET058); together these encompass the species’ full range. Another important bird found at the site is Serinus xantholaema, which although uncommon has recently been found breeding at Arero, the first breeding record for Ethiopia. A recent survey recorded 168 species at the site, of which 43 were Somali–Masai biome species including Turdus tephronotus, Cisticola bodessa, Sylvia boehmi, Cisticola nanus, Batis perkeo, Turdoides aylmeri, Parus thruppi, Dryoscopus pringlii, Onychognathus salvadorii, Lamprotornis shelleyi, Pseudonigrita cabanisi and Serinus donaldsoni.
Non-bird biodiversity: None known to BirdLife International.
BirdLife International (2018) Important Bird Areas factsheet: Arero forest. Downloaded from http://www.birdlife.org on 16/10/2018.