Our Own Published Research Papers

The myth of the lead mare

The idea that there is one “lead mare” who guides the group at all times has become a popular one, but when you watch groups of domestic horses, it often doesn’t seem to apply. Any one of them appears to be able to move off in any direction, and others may or may not follow. Sometimes they all move together, and sometimes they don’t.

Of course, this may be because our horses are kept in a confined space and perhaps don’t show the same behaviour in the natural, wild setting.

To put this to the test, we observed four groups of semi-wild horses, living under natural conditions in the Abruzzo mountains in Italy.

We studied the factors that affect the likelihood of a horse initiating movement of other members of the group: social rank, friendly relationships, spatial position, and social network, and we looked at whether group members join a movement in dominance rank order.

We found that whereas moving the group by herding is exclusive to alpha males (the highest ranking stallion in the group), any group member may initiate movement by departing from the group.   However, the likelihood that a departing horse will be followed is greater if it is high ranking, and horses usually follow a departing horse  in rank order.

Photo a, on the left, shows one mare departing from the group and others starting to follow, while photo b, on the right, shows typical herding by an alpha stallion.

This indicates that the idea of a single “lead mare” who always leads the group is a myth. Leadership is, in fact, distributed mostly over the higher ranking individuals, but any horse can suggest movement and may be followed by others.

Movement initiation in groups of feral horses (Krüger, K. Flauger, B., Farmer, K., Hemelrijk, C. Behavioural Processes 103, 2014)