Spatial distribution patterns of sheep following manipulation of feeding motivation and food availability

We hypothesised that (i) increased feeding motivation will cause sheep to move further apart as a result of individuals trying tofind food and (ii) in conditions of high food availability, sheep will move less and show greater social attraction. The effects ofboth feeding motivation and food availability on spatial distribution was examined in eight groups of food-deprived (high feedingmotivation) and satiated (low feeding motivation) sheep in good or poor food resource plots in a 232 design. Distance travelledwas assessed using Global Positioning System collars, grazing time using scan sampling and social cohesion using proximitycollars that record the number and duration of encounters within 4m. Food-deprived sheep in the good-resource plots grazed themost, whereas satiated sheep in the poor-resource plots grazed the least ( P50.004). Food deprivation had no significant effecton the number or duration of encounters and feeding motivation appeared to have little effect on spatial distribution. Contraryto expectation, sheep had more encounters ( P50.04) of a longer total duration ( P50.02) in poor-resource plots than ingood-resource plots, indicating that sheep were showing more social cohesion if food was scarce. Our findings suggest thatwhen food is scarce, animals may come together in an attempt to share information on food availability. However, when a highlypreferred food is abundant and well dispersed, they may move apart in order to maximise the intake. It is concluded that theparticular details of our experiment, namely the even distribution or absence of a highly preferred food, affected spatialdistribution patterns as sheep tried to find this food and maximise the intake.