In Clover the Cow, a pregnant cow worries about how she'll cope if the drovers start moving the herd before she gives birth. And dear, gentle Clover has a surprise in store for the drovers. Herds, or mobs, of beef cattle are sometimes moved from one place to ather in search of feed. People go with the mob to make sure they are safe and moving in the right direction -- those people are called drovers or stockmen . These days, droving is often done on motorbikes, but there are still some who travel with the mob on horseback.