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Eastern Kenya (eastern + kenya)

Distribution by Scientific Domains

Earth and Environmental Science	50%

Selected Abstracts

Stratigraphic and geochronological context of human habitation along the Galana River, Kenya

GEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 7 2007
David K. Wright
Geoarchaeological investigations along the Galana River, eastern Kenya, document a pattern of channel aggradation and then degradation from the Middle to Late Holocene. Archaeological occupations at six sites in fluvial terraces along a ,100 km stretch of the Galana River in Tsavo East National Park correspond with fluvial aggradation beginning ca. 6000 years ago. Artifact analyses indicate that the inhabitants of these sites utilized ceramics and stone tools similar to Pastoral Neolithic traditions detected at other penecontemporaneous archaeological sites in East Africa and possessed domesticated cattle from ca. 3700 years ago. The site occupations that occur during this period have dense artifact concentrations of predominantly locally procured items. The Galana River incised after ca. 900 years ago and there is a noticeable paucity of archaeological material, reflecting more peripatetic lifestyles. This shift in settlement pattern may reflect a decrease in reliance on riverine food sources during the Late Holocene, with diminished riparian environments associated with channel incision. © 2007 Wiley Periodicals, Inc. [source]

The ranging patterns of elephants in Marsabit protected area, Kenya: the use of satellite-linked GPS collars

AFRICAN JOURNAL OF ECOLOGY, Issue 2 2010
Shadrack M. Ngene
Abstract We investigated the ranging patterns of elephants in the Marsabit protected area, north eastern Kenya, to ascertain the range of bachelor and female family herds in different seasons, and to identify corridor and noncorridor areas. Data were acquired for five bachelor and four female family herds equipped with satellite-linked geographical positioning system collars, and monitored from December 2005 to December 2007. Distinct dry (about 260 km2) and wet seasons (about 910 km2) ranges were observed, with connecting corridors (north-eastern corridor: about 90 km long, about 2-7 km wide; southern corridors: about 10-20 km long, about 2-3 km wide). The dry season range corresponded with Marsabit evergreen forest, while the wet season range matched with dry deciduous lowland shrubs. The ranging elephants moved at speed of about 0.2-20 kmh,1. Bachelor herds moved faster than female family herds. Elephants moved fast during the intermediate and wet seasons than during the dry season. The speed of ranging elephants was over 1 kmh,1 in the corridor areas and about 0.2 to less than 1 kmh,1 in the non-corridor areas. Expansion of settlements towards corridor areas needs to be controlled to avoid future blocking of connectivity between wet and dry season elephant ranges. Résumé Nous avons étudié les schémas spatiaux des éléphants dans l'aire protégée de Marsabit, au nord-est du Kenya, pour évaluer le domaine vital des hardes de mâles et des hardes matriarcales à différentes saisons, et pour identifier les zones qui sont, ou pas, des corridors. Nous avons récolté des données pour cinq hardes de mâles et quatre hardes matriarcales équipées de colliers émetteurs reliés par satellite à un système de positionnement mondial, et nous les avons suivies de novembre 2005 à décembre 2007. Nous avons observé des domaines distincts de saison sèche (environ 260 km²) et de saison des pluies (environ 910 km²) ainsi que les corridors qui les relient (corridor du nord-est : près de 90 km de long, entre 2 et 7 km de large environ ; corridors du sud : entre 10 et 20 km de long, de 2 à 3 km de large). Le domaine vital de saison sèche correspondait à la forêt sempervirente de Marsabit, tandis que celui de saison des pluies correspondait à des arbustes décidus secs de plaine. Les éléphants se déplaçaient à une vitesse comprise entre 0,2 et 20 km/h. Les hardes de mâles allaient plus vite que les familles de femelles. Les éléphants se déplaçaient plus vite à l'entre-saison et en saison des pluies qu'en saison sèche. La vitesse des éléphants en mouvement était de plus d'un km/h dans l'étendue des corridors et elle variait de 0,2 à moins d'un km/h dans les zones qui ne faisaient pas partie des corridors. Il faut contrôler les extensions vers les aires qui servent de corridors pour éviter tout futur blocage de la connectivité entre les espaces vitaux de saison sèche et de saison des pluies. [source]

Bat species diversity and distribution in three vegetation communities of Meru National Park, Kenya

AFRICAN JOURNAL OF ECOLOGY, Issue 3 2004
Paul W. Webala
Abstract Diversity and distribution of bats was determined in four vegetation types in and around Meru National Park, Kenya between September 2000 and February 2001. Bat-habitat studies were based on plant species dominance, cover and farming activities. Bats were captured using standard mist nets (18 m long × 2 m high) erected on poles averaging 3 m. Vegetation was broadly grouped as Acacia or Combretum wooded grassland, or Acacia,Commiphora bushland and studied using the Braun-Blanquet method. Analysis of floristic similarity showed five vegetation species assemblages in the three broad categories. Four hundred and ninety-five bats representing eleven genera in seven families were recorded. These were Epomophorus labiatus, E. wahlbergi, Cardioderma cor, Lavia frons, Myotis welwitschii, Scotoecus hirundo, S. leucogaster, Pipistrellus kuhlii, Mops condylurus, Chaerephon bemmeleni, Mormopterus sp., Hipposideros caffer, H. commersoni, Nycteris arge and Rhinolophus landeri. This was the first record of N. arge, M. welwitschii, C. bemmeleni and a Mormopterus species in eastern Kenya. The Combretum community was most equitable (E = 0.51) with nine bat species records, while farming areas had only four. The low species richness and increased dominance of a few generalist species on farms may be indicative of different levels of disturbance. Résumé On a déterminé la diversité et la distribution des chauves-souris dans quatre types de végétation dans et autour du Parc National de Meru, au Kenya, entre septembre 2000 et février 2001. Les études de l'habitat des chauves-souris se basaient sur la dominance et le couvert de certaines espèces végétales et sur les activités agricoles. On a capturé les chauves-souris en utilisant les filets standards (18m de long sur 2 m de haut) fixés sur des piquets d'environ 3 m de haut. La végétation fut grossièrement regroupée en prairie arborée à Acacia ou à Combretum, ou en brousse à Acacia-Commiphora, et étudiée suivant la méthode Braun-Blanquet. L'analyse des similarités floristiques a montré cinq assemblages d'espèces végétales dans ces trois grandes catégories. On a relevé 495 chauves-souris représentant onze genres appartenant à sept familles. Ce sont: Epomophorus labiatus, E. wahlberghi, Cardioderma cor, Lavia frons, Myotis welwitschii, Scotoecus hirundo, Scotophilus leucogaster, Pipistrellus kuhlii, Mops condylurus, Chaerephon bemmeleni, Mormopterus sp., Hipposideros caffer, H. commersoni, Nycteris arge et Rhinolophus landeri. Ce sont les premiers cas rapportés pour N. arge, M. welwitschii, C. bemmemeni et pour une espèce de Mormopterus dans l'est du Kenya. La communautéà Combretum était la plus équitable (E = 0,51), avec neuf espèces de chauves-souris rapportées, alors que les aires cultivées n'en comptaient que quatre. La faible richesse en espèces et la dominance croissante de quelques espèces généralistes dans les fermes pourraient indiquer divers degrés de perturbation. [source]

Rural market imperfections and the role of institutions in collective action to improve markets for the poor

NATURAL RESOURCES FORUM, Issue 1 2008
Bekele Shiferaw
Abstract Many countries in sub-Saharan Africa have liberalized markets to improve efficiency and enhance market linkages for smallholder farmers. The expected positive response by the private sector in areas with limited market infrastructure has however been very limited. The functioning of markets is constrained by high transaction costs and coordination problems along the production-to-consumption value chain. New kinds of institutional arrangements are needed to reduce these costs and fill the vacuum left when governments withdrew from markets in the era of structural adjustments. One of these institutional innovations has been the strengthening of producer organizations and formation of collective marketing groups as instruments to remedy pervasive market failures in rural economies. The analysis presented here with a case study from eastern Kenya has shown that marketing groups pay 20,25% higher prices than other buyers to farmers while participation was also positively correlated with adoption of improved dryland legume varieties, crops not targeted by the formal extension system. However the effectiveness of marketing groups is undermined by external shocks and structural constraints that limit the volume of trade and access to capital and information, and require investments in complementary institutions and coordination mechanisms to exploit scale economies. Successful groups have shown high levels of collective action in the form of increased participatory decision making, member contributions and initial start-up capital. Failure to pay on delivery, resulting from lack of capital credit, is a major constraint that stifles competitiveness of marketing groups relative to other buyers. These findings call for interventions that improve governance and participation; mechanisms for improving access to operating capital; and effective strategies for risk management and enhancing the business skills of farmer marketing groups. [source]