Factors affecting the availability of Yellow-toothed Mole-rats Tachyorectes splendens as prey for Augur Buzzards Buteo augur in the southern

A study of rainfall, temperature range, soil softness and grass height as factors affecting availability of mole-rats as prey for Augur Buzzards was made in three different land-use areas in southern Lake Naivasha, Kenya. Mole-rat indices were highest in Mundui and lowest in Hell's Gate where they only appeared to peak during cooler months. Grass height was the most important predictor of mole-rat availability in all three sites, although the other variables rainfall, temperature range and soil conditions maybe proximate in nature and their effects on mole-rats difficult to detect. Key words: mole-rat, Augur Buzzard, prey availability, Buteo, south Lake Naivasha nonnally increase during the rainy seasons, sometimes reaching a peak of abundance well beyond the capacity of any socially-regulated raptor population to limit it. Most of the rodent-eating raptors breed during or after the rains, especially in the Lake Naivasha region, in Kenya's Rift Valley Province (Figure 1) where they have been recorded to breed during the long rains (March to May) and mid-year dry season (June to August) (Brown and Britton, 1980). These times of breeding are considered to coincide with peaks of rodent abundance as well as vegetative cover (Brown and Britton, 1980)