The population survey and threat assessment of the William’s Lark (Mirafra williamsi ) was carried out in Shaba National Reserve (0° 34’, 37° 57’ E). The reserve consisted of a low lying, semi arid plain on the southern bank of the Northern Ewaso Ng’iro River. It lies 9 km east of Buffalo springs National Reserve. William's Lark is thought to be globally threatened due to its small range in nothern Kenya where it occurs in two disjunct populations but there is no population data. The species inhabits scattered short-grass areas with low shrubs growing on rocky desert plains and red lava soils or low Barleria shrubs on rocky lava desert.

In this study we recorded a total of 25 William’s Lark in 15 1-km transects both inside and outside Shaba National Reserve. Densities of William’s lark were higher on the outside (1.12 individuals/ha) than the inside (0.43 individuals/ha; see table 1 below) of the Reserve. However the number of individuals flushed overall was similar (13 on the inside vs 12 on the outside) for both sides of the reserve. The overall density for this population of Williams Lark was 0.72 individuals/ha. There appeared to be a clear relationship between the presence of Baleria and the presence of William's Lark in the area. We flushed more birds in areas with higher percentage cover of Baleria (both inside and outside the reserve) than in areas without Baleria. The species also seemed to favour areas with less grass cover.