Beaver was one of the main animals of interest to the trappers as the fur wore well in coats and hats. Beaver hats became popular in the early 19th century but later the fashion changed. Towards the end of the century beaver became scarce in many areas and locally extinct in others. The decline in key species of fur-bearers due to over-harvesting, and the later emergence of the first regulatory laws, marked the end of the heyday of unregulated trapping. Many trappers turned to buffalo hunting, serving as scouts for the army or leading wagon trains to the American west. The trails that trappers used to get through the mountains were later used by settlers heading west.