What do you call a man who takes care of sheep in the field?

Source: Tatoeba

Sheep are feeding in the meadow.

Source: Tatoeba

Although the male goat kids are often culled because they will never produce milk, they are sometimes castrated instead and allowed to remain in the herd as a "wether". With a bell around its neck, such a "bellwether" is usually the leader for the rest of the herd.

Source: Tatoeba