Horizontal lines mark average arrival dates of older martins at established colony sites.
New hobbyists should not open housing until 4-6 weeks after the dates shown here. West of the Rocky Mountains, Purple Martins have different nesting habits. In the southwest martins nest only in old woodpecker cavities. In the Pacific Northwest, martins use gourds and single boxes, but not multiple-room houses. Your tax deductible donations support the PMCA's research, conservation, and education programs.