Surveys during October 2004 and July 2005, in and around Lake Bogoria National Reserve, Kenya, collected evidence of nine rodent species, and one species of shrew. The diversity of small mammals live-trapped within a single habitat type was low compared to similar studies in Africa. The low diversity may be due to the short timeframe in which trapping was conducted resulting in a lack of seasonal variability. It is likely that the high numbers of cattle and goats within the reserve negatively affected the diversity of small mammals. The presence of livestock within protected areas in Kenya has become increasingly common and this may have negative affects on biodiversity.