Ethiopian montane moorlands
Ethiopian montane moorlands are a unique and significant biome located in the highlands of Ethiopia, Eritrea, and northern Somalia, characterized by their rugged mountain landscapes. These moorlands exist above 9,842 feet (3,000 meters) and account for over three-fourths of the land at this elevation, forming the largest Afro-Alpine region in Africa, spanning approximately 9,700 square miles (25,120 square kilometers). The climate in this region is complex, with varying rainfall and temperatures, leading to a diverse range of flora and fauna adapted to high altitudes.
The vegetation primarily consists of grasslands and heathland scrub, with notable species including the giant Lobelia rynchopetalum and various herbs and grasses. This environment hosts endemic animals such as the endangered Ethiopian wolf, which thrives in the moorlands and preys on subterranean rodents. Conservation efforts in the region include protected areas like Bale Mountains National Park and Simien Mountains National Park, which help safeguard the unique biodiversity and habitats against threats such as climate change and agricultural expansion. Despite their remoteness, these moorlands face challenges from human activities, making the need for preservation increasingly critical.
Ethiopian montane moorlands
- Category: Grassland, Tundra, and Human Biomes.
- Geographic Location: Northeastern Africa.
- Summary: The Ethiopian montane moorlands are less developed than other East African moorland areas, most of which are losing habitat to expansion of high-altitude agricultural activities and livestock grazing.
The Ethiopian Montane Moorlands biome is a rugged series of mountain-based habitat located in Ethiopia, Eritrea, and northern Somalia. The highlands are divided into three ecoregions that are zoned by elevation: the Ethiopian montane forests, located at an elevation of 3,608–5,905 feet (1,100–1,800 meters); Ethiopian montane grasslands and woodlands, found at 5,905–9,842 feet (1,800–3,000 meters); and Ethiopian montane moorlands, which are located above 9,842 feet (3,000 meters) and compose more than three-fourths of the land above this altitude.
This is the largest Afro-Alpine region in Africa, extending across an area of 9,700 square miles (25,120 square kilometers). The climate is considered complex, with annual rainfall at its greatest in the southwest, at 98 inches (2,500 millimeters), and as little as 38 inches (1,000 millimeters) in the north. The annual mean temperature range on the higher peaks is 43–54 degrees F (6 to 12 degrees C). Frosts are common throughout the year, especially in the months of November through March.
Vegetation
These semiarid montane moorlands lie above the tree line, and vegetation, known as wurch to Ethiopians, consists of grasslands and moorlands filled with herbs. Trees are all but absent at such high elevations. The main vegetation types are scrub, grassland, and herb meadow. Much of the montane vegetation is a heathland scrub around 19–39 inches (0.5–1.0 meter) high, dominated by Philippia, the tree-heather Erica arborea, and other shrub species; along with the small plants Helichrysum, Alchemilla, and Cerastium; and the grasses Koeleria spp.
There is very little vegetation on the steep rocky slopes and cliffs in the high-elevation regions. Flat swamp areas are dominated by the sedge Carex monostachya. The giant Lobelia rynchopetalum, which grows to nearly 20 feet tall when fully flowered, is a distinctive feature of plant life at this elevation. All vegetation found in the Afro-Alpine zone shows xeromorphic characteristics, that is, leaves and other features adapted to retain water and reduce transpiration.
Characteristic Animals
The high-altitude environment means that endemic species (those found nowhere else on Earth) often display a number of unique behavioral, morphological, and physiological adaptations. Notable species at this elevation include endangered mammals such as the Ethiopian wolf (Canis simensis), one of the rarest canids in the world. Also known as the Simien fox, the Ethiopian wolf lives in open moorlands higher than 9,842 feet (3,000 meters). Bale Mountains National Park, which has one of the highest proportions of endemic species of terrestrial habitats in the world, contains the largest population of these wolves.
The Ethiopian wolf may have evolved from a shared ancestor of the grey wolf (Lupus lupus) that made its way to northern Africa from Europe in the late Pleistocene Period. The northern population of Ethiopian wolf is considered a separate subspecies and is unique among canids as it relies primarily on subterranean rodents for food. Because of the animal's adapted diet, the Ethiopian wolf has been able to thrive in these high-altitude areas where rodent biomass is extremely high.
The giant mole-rat (Tachyoryctes macrocephalus) and Starck's hare (Lepus starcki), also endemic to the park, compose the largest portion of the Ethiopian wolf's diet. Other mammals in the ecoregion include giant Nikolaus mouse, Ethiopian narrow-headed rat, gray-tailed narrow-headed rat, black-clawed brush-furred rat, the critically endangered Walia ibex (Capra walie) and the endangered mountain nyala. Gelada baboons, klipspringer and rock hyrax (Procavia capensis) are also found in the rocky habitats of this ecoregion.
This avian-friendly biome provides ample water in the form of alpine lakes and streams. Significant numbers of Palaearctic birds winter here, with several thousand wigeon (Anas penelope) and shovelers (A. clypeata) observed in the Bale Mountains, along with waders such as ruffs (Philomachus pugnax) and greenshanks (Tringa nebularia).
Globally threatened species found in the Bale Mountains include the wattled crane (Grus carunculatus).
The Bale Mountains are among the few known breeding sites outside the north temperate zone for such boreal species as the golden eagle (Aquila chrysaetos), red-billed chough (Pyrrhocorax pyrrhocorax), and ruddy shelduck (Tadorna ferruginea). The near-threatened pallid harrier (Circus macrourus) and Abyssinian longclaw (Macronyx flavicollis) also are found in this region.
Plant and animal colonists traveled several routes to get to these remote highlands, mostly from the dry lowlands surrounding the region. A number of tropical species arrived from the moist areas in the south and southwest, passing through the formidable barriers of the Kenyan deserts in the south and the White Nile floodplains in the west. The low trench of the East African Rift Valley may have further isolated species, by dividing the northern and southern massifs. The ecoregion is naturally very fragmented because it occurs only in the highest portions of the Ethiopian Highlands.
Conservation
Ethiopia has established two major protected areas: Bale Mountains National Park in the southern highlands; and Simien Mountains National Park in the north, which includes Ras Dashen, the highest point of Ethiopia at 15,578 feet (4,620 meters). The Bale Mountains are the largest continuous area above 9,852 feet (3,000 meters) on the African continent.
Numerous alpine lakes are found in this region, some of which persist year-round, providing valuable habitat for migratory Palaearctic waterbirds. These higher elevations are sparsely populated, although agricultural activities continue at considerable elevations wherever it is still possible to grow sufficient food to survive. There are approximately 950 vascular plant species with at least 15 site endemics in the Bale Mountains.
The Simien Mountains National Park was designated a World Heritage in Danger site from 1996 to 2017 by the United Nations Educational, Scientific and Cultural Organization (UNESCO) in part to protect it from extreme overgrazing. Outside the protected areas, other habitat blocks are relatively intact when they are too high to be used by people for cultivation or grazing. Agriculture decreases above 10,500 feet (3,200 meters), where barley is the only crop that can be cultivated.
The lower reaches of the range are more suitable for growing barley than the upper, less vegetated areas, but mostly the area is being used for cultivation and pastoralism.
Overgrazing and other human-driven activities have disrupted plant and wildlife habitats throughout the region. Rising temperatures due to climate change have further impacted the area by shrinking the size of the ecoregion, which could even lead to its eventual disappearance as average temperature increases push habitat zones farther upslope. Habitat loss due to climate conditions, and threats such as hybridization of native ungulates with free-ranging domestic goats, are negatively impacting the populations of endemic animal species, such as the Walia ibex, and taking its toll on other animal species as well.
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