The long-eared owl is one of the least known UK breeding birds, with welfare tied to adequate small mammal prey availability and the persistence of suitable nesting structures in woodland edge habitats.
Long-eared owls breeding in areas with vole population crashes face food shortages that cause breeding failure and adult mortality. Loss of woodland edge with appropriate nesting structures removes breeding sites. Winter mortality during cold spells when hunting is impaired depletes the population. The scarcity of suitable nest structures and prey may limit population recovery even in appropriate habitat.