State Museum of Natural History
Biodiversity Data Centre

Asio otus (Linnaeus, 1758)

  • Strix otus Linnaeus, 1758
Vernacular Name
Northern Long-eared Owl, Long-eared Owl
Conservation status
Value of species
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern. Partners in Flight Science Committee (2013) estimated the global population to number 50,000 individuals. The European population is estimated at 304,000-776,000 pairs, which equates to 609,000-1,550,000 mature individuals (BirdLife International 2015). Europe forms approximately 28% of the global range, so a very preliminary estimate of the global population size is 2,180,000-5,540,000 mature individuals, although further validation of this estimate is needed. Trend Justification: This species has undergone a small or statistically insignificant decrease over the last 40 years in North America (data from Breeding Bird Survey and/or Christmas Bird Count: Butcher and Niven 2007). In Europe the population size trend is unknown (BirdLife International 2015). The long-eared owl's breeding season is from February to July. This bird is partially migratory, moving south in winter from the northern parts of its temperate range. Its habitat is forest close to open country. Overall, these owls are secretive, and are rarely seen.[citation needed] It nests in trees, often coniferous, using the old stick nests of other birds such as crows, ravens and magpies and various hawks. The average clutch size is 4–6 eggs, and the incubation time averages from 25–30 days. It will readily use artificial nesting baskets. An unusual characteristic of this species is its communal roosting in thickets during the winter months. The young have a characteristic call, likened to a rusty hinge. The long-eared owl hunts over open country by night. It is very long winged, like the similar short-eared owl, and glides slowly on stiff wings when hunting. Its food is mainly rodents, small mammals, and birds. In Europe it faces competition from the tawny owl and is most numerous in localities where the tawny is absent, notably in Ireland, where the long-eared is the dominant owl; it can occasionally be seen even in Dublin city centre.
Book reference
  • Котенко Т.И., Ардамацкая Т.Б., Дубина Д.В. и др. Биоразнообразие Джарылгача: современное состояние и пути сохранения // Вісник зоології. – 2000. – Спец. випуск. – 240 с.
  • Літопис природи. Природний заповідник «Медобори». 2018, т.26. – Гримайлів, 2019. – 509 с.
  • Літопис природи. Природний заповідник «Розточчя». 2018, т.32. – Івано-Франкове, 2019. – 000 с.
  • Проект організації території Чорноморського біосферного заповідника НАН України та охорони його природних комплексів. Ч. 1. К.- 2016. 300 с.

Taxonomic branch