Bale Mountains National Park
Bale Mountains National Park (BMNP) is a national park of Ethiopia. The
park encompasses an area of approximately 2,150 square kilometres (530,000
acres) in the Bale Mountains and Sanetti Plateau of the Ethiopian Highlands.
The park's Afromontane habitats have one of the highest incidences of
animal endemicity of any terrestrial habitat in the world. The park was
nominated to the World Heritage Tentative List in 2009.
Geography
Bale Mountains National Park is located in southeastern Ethiopia, 400
km southeast of Addis Ababa and 150 km east of Shashamene in the Oromia
Region National State.
The boundary of the BMNP lies within five woredas (districts): Adaba (west),
Dinsho (north), Goba (northeast), Delo-Mena-Angetu and Harena-Buluk (southeast).
The park area is encompassed within geographical coordinates of 6º29'
– 7º10'N and 39º28' – 39º57'E.
The Bale Mountains are part of the Bale-Arsi massif, which forms the western
section of the southeastern Ethiopian Highlands.
Geology and glaciation
The Bale Mountains were formed prior to the formation of the Great Rift
Valley, from lava outpourings which covered all underlying rock formations
between 38 and 7 million years ago. The rocks of the volcanic outpourings
are predominantly trachytes, but also include rhyolites, basalts, and
associated agglomerates and tuffs. The main Bale highlands consist of
the vast lava Sanetti Plateau, with at least six volcanic cones, each
more than 4,200 meters high and considerably flattened by repeated glaciations.
There have been at least two glacial periods in the history of the mountains
and they were glaciated as little as 2,000 years ago. During the Last
ice age, the Bale Mountains were one of the most extensively glaciated
areas in present-day Ethiopia, with a total area of ice in Bale of approximately
180 km2. There was a 30 km2 ice cap around the peak of Tulu Dimtu (the
second highest mountain in Ethiopia) on the Sanetti Plateau and individual
glaciers of considerable thickness reached down to 3,200 meters. As a
consequence, the landscape as we see it today is the lava outpourings
much modified by over 20 million years of erosion by water, wind and ice.
There are certain geological features that remain an enigma to geologists
and glaciologists such as the striations that appear on shallow hillsides
on the Sanetti Plateau. Boulder grooves (large stone sorted stripes two
to four meters wide and eighty meters long), till ridges and numerous
glacial valleys, such as the Togona Valley on the northeast facing slopes
of the Sanetti Plateau, provide evidence of the ice-age effects on the
landscape of BMNP. Until the beginning of deglaciation (13,000 to 14,000
years ago) the snowline was at 3,700 meters and the upper tree limit in
the Bale Mountains was well below 3,000 meters. Fluctuations in climate
over the last historical period, including the last 3,000 years, have
dramatically affected the vegetation and other biodiversity in the highlands.
Hydrology
The Bale Mountains play a vital role in climate control of the region
by attracting large amounts of orographic rainfall, which has obvious
implications for livestock and agricultural production. Some 600 - 1,000
mm fall annually in the lower altitude areas, while 1,000 - 1,400 mm fall
in areas of higher altitude, and over 12 million people from Kenya, Somalia
and Ethiopia are dependent on water from the Bale massif.
A total of 40 rivers rise in the BMNP area, contributing to five major
rivers: the Web, Wabe Shebele, Welmel, Dumal and Ganale. Additionally,
the Bale massif is the source for many springs in the lowlands, which
are of paramount importance as they are the only source of water year-round.
People living south of the national park are completely dependent on good
management of the water resources from the highland areas. If the flow
of these rivers is altered in any way – through deforestation, overgrazing
of pastures and/or over abstraction for irrigation (all of which are occurring
at present) – a highland/lowland imbalance results with loss of perennial
water in the lowlands. If such a situation arises, the dry season range
of the people and their livestock reduces dramatically and they concentrate
about whatever water source remains. It is widely recognized that such
uneven distribution of people and livestock leads to rapid and lasting
degradation. The people are, therefore, likely to become increasingly
food-aid dependent if the water catchment areas of the Bale Mountains
are insufficiently protected. There is already evidence that over abstraction
of water in the Bale Mountains is occurring.
Furthermore, two rivers emanating from Bale, the Wabe Shebele and Yadot,
(tributary of the Ganale) have hydroelectric schemes. The dam on the Yadot
River supplies electricity to Delo-Mena, while the dam on the Wabe Shebele
provides electricity to the Bale area.
Lastly, there are numerous natural mineral water springs, locally called
horas, which provide an essential source of minerals for livestock. The
mineral springs within the park are valued for their high mineral content
(sodium, potassium, magnesium, zinc and calcium), and local pastoralists
believe that in order to maintain good health and milk production their
livestock must be given hora water. They will drive their livestock for
up to two days to reach the hora springs. It is increasingly apparent,
however, that the hora springs have become an excuse for local people
to enter the park to gain access to better grazing areas.
Climate
Temperatures vary widely throughout BMNP: on the plateau, daytime temperatures
are usually around 10 °C (50 °F) with strong winds; in the Gaysay
Valley average daytime temperatures are around 20 °C (68 °F),
and the Harenna Forest is around 25 °C (77 °F). However, weather
changes frequently and sometimes drastically. In elevations over 3,000
meters, night frosts are common. The rainy season is from May until November.
Ecology
Habitats
The park is divided into five distinct and unique habitats: the Northern
Grasslands (Gaysay Valley), Northern Woodlands (Park Headquarters), Afro-alpine
Meadows (Sanetti Pleateau), Erica Moorlands, and the Harenna Forest.
Habitats of the Bale Mountains National Park range from grassland areas
around 3,000 metres (9,800 ft) in elevation, to Mount Tullu Demtu, the
second highest point in Ethiopia at 4,377 metres (14,360 ft) above sea
level.
Surrounded by East African pencil juniper (Juniperus procera) trees and
St. John’s wort, waist-high wildflowers and grasses grow in the Northern
Grasslands and Woodlands. Tree heath (Erica arborea) is native to the
Ethiopian montane moorlandsecoregion in the park.
The Afro-alpine moorlands of the Sanetti Plateau is the largest continuous
area of its altitude on the entire continent of Africa. Carpeted in lichen
covered rocks, and punctuated by Giant lobelia (Lobelia rynchopatelum)
that grow to heights of up to 12 meters. The Plateau is also dotted with
alpine lakes and streams, providing important resident wildlife resources,
as well as wintering and passage stations for rare and regionally endemic
birds.
The Harenna Forest plant community makes up about half of the park, a
woodland of trees draped in moss and lichens that seem to drip off the
branches. The area is frequently cloaked in fog, and wildlife is elusive.
Fauna
The Bale Mountains National Park is an important area for
several threatened Ethiopian endemic species. Additionally, the park holds
26% of Ethiopia’s endemic species including one primate, one bovid, one
hare, eight rodent species, and the entire global population of the big-headed
African mole-rat. There are also several rare and endemic amphibians.
Mammals
Mammal species in the Bale Mountains National Park include Ethiopian wolf
(Canis simensis), Mountain nyala (Tragelaphus buxtoni), big-headed African
mole-rat, bushbuck, common duiker, klipspringer, Bohor reedbuck, warthog,
spotted hyaena, serval.[1] and the Bale Mountains vervet (Chlorocebus
djamdjamensis).
Other mammals of Bale Mountains National Park include the Cape bushbuck,
African golden wolf, spotted hyena, colobus monkey, lion, African leopard,
and African wild dog. Almost one third of the 47 mammals that live in
BMNP are rodents. The rodent community, particularly of the Afro-alpine
plateau are keystone species in the Bale Mountains National Park. They
are the main prey for Ethiopian wolf, and natural grazers of the Afro-alpine
areas where important cryoturbation processes happen.
The Afro-alpine area is home to over half of the global population of
the Ethiopian wolf, the rarest canid in the world with only 400 animals
surviving. The northern juniper-hagenia woodlands harbor the largest population
of the endemic and similarly endangered Mountain nyala, estimated to be
approximately two-thirds of the global population. The Ethiopian wolf
is restricted to just six isolated mountainous areas of the Ethiopian
Highlandsand is protected in the country from any activities that may
threaten its survival. Habitat loss, caused by unsustainable and rapidly
expanding cattle and crop farming is the most severe threat, but diseases
like rabies and canine distemper transmitted from domestic dogs are a
serious immediate threat and have recently caused population crashes in
the Bale Mountains.
Flora
Bale Mountains National Park is home to 1,321 species of flowering plants,
163 of which are endemic to Ethiopia (12%), and 23 to Bale alone (14%
of Ethiopia’s endemic plants).
The forests of the Bale Mountains are important for genetic stocks of
wild forest coffee (Coffea arabica) and for medicinal plants in Ethiopia.
Three medicinal plant hotspots have been identified: two in the Gaysay
area and one in the Angesu area, spanning the park boundary. The female
flowers of hagenia contain anthelmintic, which is used to treat tapeworms
among the local populations. St. John’s wort is used to combat depression.
A 2006 study estimated the value of the medicinal plants industry to be
approximately two billion Ethiopian birrannually, some 8% of Ethiopia’s
Federal budget at the time.
Avifauna
Rated by the African Bird Club as the number four birding site in Africa,
the Bale Mountains are home to over 282 species of birds, including nine
of the 16 species endemic to Ethiopia. Furthermore, over 170 migratory
birds have been recorded within the park. Bale Mountains National Park
is home to almost every highland Abyssinian and Ethiopian endemic.
With over 863 species of birds recorded, representing approximately 9.5%
of the world’s bird diversity and 39% of the bird species in Africa, Ethiopia
is often considered one of the most avifaunal-rich countries in Africa.
Sixteen of Bale’s bird species are endemic to Ethiopia.
Due to the diversity and density of rodents, the Bale Mountains are also
an extremely important area for resident as well as wintering and passing
raptors.
Ethiopian endemic birds found in the Bale Mountains include: blue-winged
goose (Cyanochen cyanoptera), spot-breasted lapwing (Vanellus melanocephalus),
yellow-fronted parrot (Poicephalus flavifrons), Abyssinian longclaw (Macronyx
flavicollis), Abyssinian catbird (Parophasma galinieri), Bale parisoma
(Parisoma griseiventris), Ethiopian siskin (Serinus nigriceps), fawn-breasted
waxbill (Estrilda paludicola) and the Abyssinian owl (Asio abyssinicus).
Activities
The Bale Mountains National Park is open year-round although the most
popular time to visit is November through April when the rains have stopped.
The park can be reached by private car or public transportation from Addis
Ababa. Visitors may choose to trek throughout the park either by horseback
or on foot, or alternatively to visit the park entirely by car. Treks
range from one to 12 nights and travel through all the different ecosystems
of the park.
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