can be subject to predation by other predatory birds such as jays, hawks, and owls. Breeding Elf owls usually choose abandoned, north-facing woodpecker cavities in saguaro cacti, sycamores, cottonwoods, and other hardwood trees, to raise their young. While some cavity nesters utilize vegetation as nesting substrate, elf owls have been observed removing this vegetation and prefer a bare cavity. While elf owls primarily use natural structures for their nesting, they have been known to nest in man-made structures such as telephone poles in urban areas. As populations decrease due to encroachment by urbanization, this may serve elf owls well (for more, see Conservation status). They generally mate for periods of three months, with male and female birds remaining in close proximity. During this time, females engage in the singing of locational calls (see Description for more information on elf owl vocalizations), and males respond with mating rituals of their own. Males and female forage independently during this time, but the male elf owl will often hunt for the female as she remains in the pairs' chosen habitat for the mating season. While three eggs is a very common clutch size, females may lay anywhere from one to five eggs in springtime (late March to early May). The eggs are usually round or oval shaped with a white coloration and are from 26.8 x 23.2 to 29.9 x 25.0 mm in size. The eggs are incubated for about 24 days before the chicks hatch. The young owlets fledge at about 10 weeks. Usually, chicks are born in mid-June or early July. By the end of July, they are almost always fledged and ready to set out on their own. After the young hatch, the female elf owl watches over them in the nesting cavity while the male often hunts for the young and the female herself. The male elf owl does most of the caretaking himself, feeding his brood independent of the female, who resides in the cavity. Generally this period of communal rearing lasts until the brood is 17 to 21 days of age. Elf owls live 3 to 6 years; in captivity they may live up to 10 years. The most common types of mortality for these owls are predation, exposure, and inter-species as well as intra-species competition. Food and feeding Hunting is performed mostly during nocturnal hours. Straight line flight is often deployed for this purpose but they