Characteristics of flock structure in Sheep

Characteristics of flock structure.

Research has shown
that different breeds have different flock structures
(Arnold et
al., 1981):
1. Merinos are a tightly knit flock and rarely form subgroups.
They graze close to each other and disperse
into sub-groups only under extreme food shortage,
when sex and age groups segregate out.
2. Southdowns usually form a few sub-groups and are
closely associated when grazing, but not when camping.
3. Dorset Horns always form many sub-groups.
In cases where sub-groupings occur, the flock maintains
a social entity because membership of sub-groups
is constantly changing. The identification of a flock
structure is important to understand when managing
sheep. One important aspect is that, irrespective of
breed, flocks of sheep drawn from different sources do
not readily integrate into a socially homogeneous group
(Winfield et al., 1981). This means that if the paddock is
large enough, each group will use a different area, even
if the food is better in one part. This can lead to some
sheep being under-nourished.
In a gregarious breed, such as Merinos, the flock
moves as a unit and is unsuited to grazing in pastures
that are not uniformly abundant. The net effect of such
behaviours, particularly on an extensive scale, is that to
increase or decrease stocking rate will not necessarily
lead to improved animal production of an area. This is
because the non-random spread of animals in that grazing
area makes some sectors virtually psychologically
unavailable to some individuals.



http://animalbehaviour.net/JudithKBlackshaw/JKBlackshawCh3b.pdf