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The patterns of richness, diversity and similarity in rodent communities in agricultural areas and in adjacent Kindoroko Forest Reserve in the North Pare Mountains, Tanzania were assessed. By using a capture-mark-recapture method, 289 individuals of nine rodent species in March and May 2011 were captured. Seven species were recorded in agricultural area and 5 species in the Forest Reserve. Multimammate Rat (Mastomys natalensis) was abundant in agricultural area while soft-furred mouse (Praomys delectorum) was dominant in the Forest Reserve. Species diversity was greater outside than inside the forest, supporting results of earlier studies. Species similarity between the two habitats was high indicating that the species were generally evenly distributed across the landscape. The results showed the importance of agricultural land to the rodent community. Differences in rodent diversity between the two areas could be attributed to the availability of food and the heterogeneous environment in agricultural areas. While the factors causing lower diversity in the Forest Reserve are not yet understood, reduced food availability and competition with herbivores could be a contributing factor. Further work to understand the factors determining habitat preferences of species for conservation and ecosystem function is recommended.Keywords: Diversity, Kindoroko, North Pare Mountains, Rodents, Tanzania

Scanning behaviour enables birds to collect information important for their survival, such as detecting predators (anti-predatory strategy) and searching for food. The scanning behaviour of the Common Ostrich Struthio camelus was investigated by determining the scanning duration (total seconds during 5-min periods that a bird’s head was raised) and scanning rate (number of times an individual raised its head per minute) among different group sizes in late 2006 in Serengeti National Park, Tanzania. A total of 14 males and 20 females were observed. Scanning duration was a function of group size where individuals in small groups scanned for longer times than individuals in large groups. However, increasing group size did not have a significant effect on the scanning rate among the groups. Individual vigilance among ostriches is influenced by group size, whereas individual scanning rate may be influenced by factors other than group size, such as body size and habitat type. Higher scanning duration in small groups is attributed to anti-predatory behaviour.