Quantitative Assessment of Grazing Behaviour of Sheep in Arid Areas

Abstract

Five indices are suggested to quantify components of spatial distribution of grazing sheep which were observed by aerial photography. Indices based on sheep numbers were more sensitive to environmental changes than those based on distances between sheep. It is suggested that the adjustment takes place by a change in the numbers within independently grazing flocks, while social contact between sheep, as reflected by various nearest-neighbour distances, remains unaltered.