Browsing by Author "Tattersfield, Peter"

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    Ecology and Conservation of the Land-Snails of the Eastern Arc Mountains
    (1998) Tattersfield, Peter; Seddon, Mary B.; Meena, C.; Kayumbo, N.; Kasigwa, Peter F.
    The history of the study of the terrestrial molluscs of the Eastern Arc Mountains is summarised and a checklist of species known from each range is presented. Current knowledge of the fauna is patchy but each of the ranges contains endemic species and collectively they support a major proportion of the Tanzanian land-snail fauna. Recent research in the East and West Usambara, Uluguru and Nguru Mountains has revealed high levels of mollusc diversity in Bomole and Monga Forests (East Usambara Mountains) and in the limestone forest at Kimboza (Uluguru Mountains); these forests support the richest faunas reported so far from East Africa. In contrast, diversity and abundance is low in the forests of the Nguru Mountains. A similarity analysis is used to identify several clusters of sites that are related to geographical position and altitude. The significance of these findings for the conservation of East African land snails is discussed.
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    High Diversity and Regional Endemism in Land-Snails of Eastern Tanzania
    (Springer Link, 1997) Emberton, Kenneth C.; Pearce, Timothy A.; Kasigwa, Peter F.; Tattersfield, Peter; Habibu, Zambia
    In February/March 1995 we collected land snails (including slugs) at 12 stations in eastern Tanzania. A total of 571 person-hours yielded 9174 snails assigned to 159 morpho-species. The richest two sites each (<4ha of uniform forest) had 50 species (Amboni Cave) and 48 species (near Amani, Usambaras), nearly as great as the most species-rich sites known in the world; sieving of litter and soil would probably yield more species. In lowland (coastal) forests, both diversity and endemism seemed to decrease from north to south. Most snail species were found within only one of four coastal or one montane geographic regions, indicating substantial regional endemism. Only one species (Achatina fulica) appeared in all five regions, and 84% of all other species were found in only one (61%) or two regions (23%). The predatory streptaxids comprised about half the species and a third of the individuals at the Usambara site, an extremely high ratio of carnivores. Small snails (< 5mm greatest adult shell dimension) – many of which are probably undescribed species – comprise a substantial proportion of Tanzanian molluscan diversity; more surveys are needed, especially because of human pressures on the few forest patches remaining.