Walia Special Edition on the Bale Mountains (2011) - Zoologische ...

History and Physical Features of the Ethiopian Highlands
The Ethiopian highlands were formed during the Oligocene and Miocene geological periods, between
38 and 7 million years ago (Miehe and Miehe 1994), before the formation of the Rift Valley that
splits the highlands into two (Yalden and Largen 1992). The highlands have a lower limit of about
1100 m a.s.l. and an area of 519 278 km2 (Williams et al. 2004). Ethiopia contains more than 80% of
the highland massif above 3000m a.s.l. on the African continent (Yalden 1983). The highlands (land
above 1500 m a.s.l.) constitute around 43% of the country and are the most densely populated areas
in the country, inhabited by 88% of Ethiopia’s human and 65% of its livestock population (Yalden
1983; CSE 1997; EWNHS 2001). This has led to land degradation through agriculture, overgrazing
and soil erosion, which are the most serious threats to the sustainability of these biologically and
ecologically important ecosystems (EWNHS 1996; Stephens et al. 2001; Williams et al. 2004).
The Bale Mountains are situated in the southeast highlands of Ethiopia, geographically
separated from the western and central highlands of the country by the Rift Valley. Located in the
centre of the Bale Mountains, the BMNP encompasses an area of 2200 km2 . The National Park
contains a landscape ranging from 1500 m a.s.l. to 4377 m a.s.l. Five main vegetation zones are
designated in this National Park: the northern Grasslands (Gaysay valley), the northern woodlands,
ericaceous forest, the Afroalpine moorland and grassland and the Harenna Forest (Hillman 1986;
Miehe and Miehe 1994; Asefa 2006-07).
The BMNP area experiences two rainy seasons: heavy rain and small rain. The heavy rain
is from July to October, with the highest peak in the August and the small rain from March to June,
with the highest peak in the April. The highest temperature recorded is 18.4oC in February and the
lowest is 1.4oC in January (Hillman 1986; Refera and Bekele 2002).
Provisional Checklist and Endemic Species of the BMNP
In this review paper, nomenclature mostly follows the names used by Hillman (1993). However,
the materials referred by Hillman (1986), Yalden (1988) and Hillman (1993) to Crocidura fumosa
from the Bale Mountains were found to be a mis-identification (Yalden and Largen 1992); thus,
as used in this paper, the one from the Harenna forest in the south side of those mountains is C.
thalia, whereas that from the north side is C. glassi. Also, the material these authors referred to as
C. baileyi is in fact C. lucina (Yalden and Largen 1992). For the remainder of species, which were
not mentioned in Hillman’s (1993) list, names follow Kingdon (2004). Deviations from these, when
deemed necessary, are indicated where appropriate.
In his pioneer work of attempting to compile a checklist of mammals of the BMNP, Hillman
(1986) listed the occurrence of 47 mammal species in the area. Six years later, he produced a revised
checklist in which he listed 66 species (Hillman 1993). Thereafter, an updated checklist of mammals
in the National Park has not been published. However, unpublished documents on mammals of the
BMNP suggest a total of 77 species in the park (Williams 2002; BMNP 2003).
<strong>Walia</strong>-<strong>Special</strong> <strong>Edition</strong> on the Bale Mountains 5