The continuing bush thinning in Soysambu Conservancy (Delamere estates) to increase the grazing fields lead to establishment of the study. The main objective of this study was therefore to determine the effectiveness of bush thinning as management tool in rangeland management and determine the utilization of the thinned areas by both livestock and wild animals while estimating the impacts on species diversity of the activity Acacia totilis, Acacia Seyal and Acacia Xanthpholea was the main target for thinning as they support growth of the lianas and other unpalatable bush. The trees grew into bushy making it inpenetratable for animal. Nevertheless, the bushes have provided a home to many small antelopes. Designated areas were set for thinning and the products used for charcoal production and firewood. Two Quadrats were set in the areas thinned to determine the forage regeneration, animal utilization of the thinned areas and presence of the palatable forage for both livestock and wildlife. Past, Current and future implications were observed. An independent quadrat was laid in un-thinned area to establish and compare the performance of the thinned and un-thinned areas in terms of biodiversity and animal habitat utilization and rangeland production. The quadrats were monitored for two months January and February 2014 on weekly basis. The height of the selected tree species was recorded in centimeters to monitor growth. Every species was counted to estimate the species diversity. Point quadrants were used to determine the grass diversity. Presence or any animal sign was recorded. A one square meter quandrat was isolated for biomass production. The palatable grasses were cut and weighed wet and dry and the results were analyzed. The results were analyzed using Shannon weinner index and regression to determine the growth and diversity as well as species evenness. Biomass production on both plots was estimated to estimate the production on the thinned and un-thinned plots. The thinned plots recorded an increasing biomass production with time as compared to bushy and un-thinned plot. The results indicated that some animals have been affected negatively. The giraffes which roamed around the area were scared by the excessive noise and left the area to occupy the areas around the Lake where human disturbance was minimal or less. Avian life was affected as nesting trees were destroyed. Zebras, goats, Impalas, cows and antelopes found better grazing fields as were seen frequenting the areas thinned. Grass species diversified and grew better as a result of the nutrients availed by the trees and shrubs thinned. A considerable number of snares were destroyed in the areas thinned as well as destruction of poacher’s hideouts. Plants species increased depending on the rainfall. Also the invasive species emerged and pose a threat to biodiversity if not controlled.