East African montane forests explained

East African montane forests
Map:Ecoregion AT0108.svg
Biogeographic Realm:Afrotropical
Biome:tropical and subtropical moist broadleaf forests
Border:East African montane moorlands
Border1:East Sudanian savanna
Border2:Northern Acacia–Commiphora bushlands and thickets
Border3:Serengeti volcanic grasslands
Border4:Southern Acacia–Commiphora bushlands and thickets
Border5:Victoria Basin forest–savanna mosaic
Area:65,500
Country:Kenya
Country1:South Sudan
Country2:Tanzania
Country3:Uganda
Coordinates:-0.55°N 35.65°W
Conservation:critical/endangered
Protected:35
Protected Ref:[1]

The East African montane forests is a montane tropical moist forest ecoregion of eastern Africa. The ecoregion comprises several separate areas above 2000 meters in the mountains of South Sudan, Uganda, Kenya, and Tanzania.

Geography

The East African montane forests extend across a total of 65500km2, in 25 separate enclaves, which range in size from 23,700 to 113 square kilometers. The montane forests extend down to approximately 1000 meters elevation, and as high as 3500 meters. The northernmost enclave is on Mount Kinyeti in the Imatong Mountains of South Sudan, extending south through Mount Moroto in eastern Uganda and Mount Elgon on the Kenya-Uganda border. In Kenya and Tanzania, the ecoregion follows the mountains east and west of the Eastern Rift and associated volcanoes, including the Aberdare Range, Mount Kenya, Mount Kulal, Mount Nyiru, Ndoto Mountains, Matthews Range, Mount Marsabit, Cherangany Hills, and the Nguruman Escarpment in Kenya, and Mount Kilimanjaro, Mount Meru, Ngorongoro, and the Marang forests (Mbulu Highlands and Mount Hanang) in northern Tanzania.

Climate

The climate of the ecoregion is more temperate and seasonal than the surrounding lowlands. Temperatures can fall below 10 °C (50 °F) in the coldest months (July and August) and rise above 30 °C (86 °F) in the warm season. Temperatures are generally lower at higher elevations, and frosts can occur at the highest elevations.

Average annual rainfall varies between 1,200 and 2,000 mm, with two wet seasons – October to December and March to June – and two dry seasons – January and February and July to October. The climate is more humid than the surrounding lowlands, and with less distinct wet and dry seasons. Rainfall varies from mountain to mountain, with elevation, and with the direction of prevailing winds.

Flora

The ecoregion consists of montane forests, grasslands, and savannas, transitioning to the East African montane moorlands on the highest peaks. The ecoregion is home to the Afromontane flora, which occurs in the mountains of eastern Africa, and is distinct from the lowland flora.[2]

Plant communities vary with elevation. Plant communities and characteristic species are generally similar from mountain to mountain. The elevational limits for plant communities can vary from mountain to mountain, depending on the mass and height of the mountain, its proximity to the ocean, and its distance from the equator – a phenomenon known as the Massenerhebung effect (mass-elevation effect).[2]

Characteristic plant communities include:[3]

Fauna

There are eight endemic or restricted-range bird species in the ecoregion. The Aberdare cisticola (Cisticola aberdare), Abbott's starling (Cinnyricinclus femoralis), and Kenrick's starling (Poeoptera kenricki) occur on only two or three mountains or mountain ranges in the region. The Hunter's cisticola (Cisticola hunteri), Jackson's francolin (Francolinus jacksoni), and Sharpe's longclaw (Macronyx sharpei) range over most of the mountains in the ecoregion.

Endemic mammals include the shrews Peters's musk shrew (Crocidura gracilipes), Rainey's shrew (Crocidura raineyi), Ultimate shrew (Crocidura ultima), Aberdare mole shrew (Surdisorex norae), and Mount Kenya mole shrew (Surdisorex polulus), and the rodents Grammomys gigas, Tachyoryctes annectens, and Tachyoryctes audax.

Limited-range mammals native to the montane forests include Jackson's mongoose (Bdeogale jacksoni), Abbott's duiker (Cephalophus spadix), Zanj sun squirrel (Heliosciurus undulatus), and eastern tree hyrax (Dendrohyrax validus).

There are nine endemic species of reptiles in the ecoregion, including six species of chameleons, most limited to a single mountain or range, and the montane viper (Vipera hindii).

Protected areas

35% of the ecoregion is in protected areas. Protected areas include Aberdare National Park, Mount Kenya National Park, Mount Elgon National Park, Kilimanjaro National Park, Arusha National Park, Kidepo Valley National Park, Kidepo Game Reserve, Mathews Range Forest Reserve, Mount Nyiru Forest Reserve, Pian Upe Wildlife Reserve, Ngorongoro Conservation Area, and Lake Bogoria National Reserve.[1]

External links

Notes and References

  1. "East African montane forests". DOPA Explorer. Accessed 1 February 2021. https://dopa-explorer.jrc.ec.europa.eu/ecoregion/30108
  2. Kindt, R., van Breugel, P., Lillesø, J-P. B., Bingham, M., Demissew, S., Dudley, C., ... Graudal, L. O. V. (2011). Potential natural vegetation of Eastern Africa (Ethiopia, Kenya, Malawi, Rwanda, Tanzania, Uganda and Zambia): Volume 2: description and tree species composition for forest potential natural vegetation types. Forest & Landscape, University of Copenhagen. Forest & Landscape Working Papers, No. 62/2011
  3. Kindt R, van Breugel P, Lillesø J-PB, Gachathi F, Omondi W,Jamnadass R, and Graudal L. 2011: Potential natural vegetation of eastern Africa. Volume 8. Atlas and Tree Species Composition for Kenya. Forest & Landscape working paper xx-2013
  4. Lillesø, J-P.B., van Breugel, P., Kindt, R., Mbago, F., Moshi, H.N., Ndangalasi, H.J., Uronu, L.O.N., Jamnadass, R. and Graudal, L. 2014: Potential Natural Vegetation of Eastern Africa. Volume 10. Atlas and tree species composition for Tanzania. Department of Geosciences and Natural Resource Management, University of Copenhagen.