Transhumance is the seasonal movement of people with their
livestock between fixed summer and winter pastures. In
montane regions (
vertical transhumance), it implies movement between higher
pastures in summer and lower valleys in winter. Herders have a permanent home, typically in valleys. Generally only the
herds travel, with a certain number of people necessary to tend them, while the main population stays at the base. In contrast,
horizontal transhumance is more susceptible to being disrupted by climatic, economic or political change.