To study the use of Jumping Cholla cacti (Opuntia fulgida) by birds for nesting, I searched a 200-square-meter area at Organ Pipe Cactus National Monument, Arizona, in April 1987. It was also my aim to find out if nesting birds select particular heights of cacti. Sixty-three bird species breed in Organ Pipe Cactus National Monument (Huey 1942; Groschupf et al. 1987).