In Spain, researchers studied eagle-owls in several ways. From 2004 to 2012, they monitored 253 eagle-owl territories from ten subpopulations in the Iberian Peninsula. They also genotyped 235 eagle-owls from ten Spanish subpopulations using eight microsatellite markers. Bayesian analyses of those genetic markers revealed three genetic clusters, grouping subpopulations from central, south-western and south-eastern Spain. Eagle-owls are elusive, which makes them difficult to study in their natural habitats. Owl pellets are very useful to scientists because they help them understand what these hard-to-find birds eat. A pellet study in southeastern France found that the pellets showed a broad dietary range, which reflects the generalist predator behaviour of the Eagle Owl. The Eagle Owl is one of the main potential predators of small prey found in archaeological sites, according to a 2019 study of pellets in Scientific Reports.
In Spain, the eagle-owl was among the species most affected by direct human persecution and by the decline of its preferred prey, the European rabbit. That prey crashed after two viral disease outbreaks: myxomatosis in the 1950s and rabbit haemorrhagic disease in the late 1980s. Scientists think habitat choice and nesting success in eagle-owls depend mainly on having enough of certain prey, such as European rabbits. Scrub areas favour rabbit abundance, which positively influences eagle-owl breeding success. The same Spanish study found strong year-to-year changes in breeding success, which may be related to changes in the abundance of the European rabbit. Eagle-owl numbers in Spain are high where farmland supports many rabbits, but those areas are often crossed by power lines. Unlike most large raptors such as eagles or vultures, the eagle-owl has high reproductive rates, which may have favored a rapid recovery in Spain.
Direct persecution led to the extinction of the Eurasian eagle-owl in large areas of Europe, such as northern Germany in 1830, Luxembourg in 1903, Belgium in 1943, and central and western Germany in the 1960s. In Europe, the Eurasian eagle-owl's numbers fell in the first half of the 1900s, and as of November 2026 the Peregrine Fund says they are recovering but have not returned to what they were before the mid-1900s. Reintroduction programs have been run in Germany, France, Belgium, Switzerland and Scandinavia, and have faced high mortality and low reproductive success. As of November 2026, the IUCN Red List lists the Eurasian eagle-owl as Least Concern.
An eagle-owl uses keen eyesight and hearing to find prey at night, and its wing feathers are shaped to make little noise. Eagle-owls eat many kinds of animals, from beetles to fawns, and also birds, reptiles, amphibians and fish. When food is rare, eagle-owls will hunt during the day.
Eagle-owls are largely solitary except when pairing up to breed. They often pair up for life. They prefer to stay in the same territory unless food shortages force them to leave. A Eurasian eagle-owl pair's young leave the nest area and usually stay in their parents' territory for another 3 to 4 months before looking for a territory of their own. A zoo raptor group says eagle-owl young are independent at 150 to 160 days of age.
Words to know
- genotyped: read genes
- subpopulations: local groups
- persecution: direct harm
- raptors: birds of prey
