 Bells are used to keep track of grazing animal herds such as goats, reindeer, sheep and cows.They are mainly used in Europe, Mediterranean areas and Latin America, but are also used worldwide by those who practice transhumance, including nomadic pastoral tribes in Africa and Asia.Some people put bells on their livestock because they believe the foreign sound of the bell scares off predators, however, some studies have shown that the sound of the bell has the opposite effect and leads predators to livestock because predators develop a learned association between the sound of the bell and the presence of a prey animal.