Densities of breeding birds are relatively low, except when local food and nesting habitat availability allow loosely colonial nesting. Captive Long-eared Owls have been known to live for over 10 years. Many are killed by shooting and collision with vehicles. Natural enemies of adult birds include Great Horned and Barred Owls. Raccoons are major predators of eggs and nestlings.
Populations fluctuate regularly with prey abundance.
Overall populations are thought to be declining in North America because of the loss of riparian nesting habitat through urban and agricultural development. Pesticide use may have secondary effects on Long-eared Owls. Useful habitat enhancements include retention of fallow fields, elimination of vast monocultures, decreased use of pesticides, and planting of conifer groves. Breeding habitat must include thickly wooded areas for nesting and roosting with nearby open spaces for hunting. During winter, they need dense conifer groves or brushy thickets to roost in.