Dietary biology of the Eurasian eagle-owl
In rare cases, other predators may kill a Eurasian eagle-owl. In Europe, there is one case of a white-tailed eagle killing an eagle-owl and there are at least four known incidents of eagle-owls being killed by golden eagles. Also, an eagle-owl was found among the prey remains at a golden eagle eyrie in Mongolia. An eagle-owl was also found amongst the prey in the nest of steppe eagles ("Aquila nipalensis") in Altai Krai, Russia. In 2016, a large female subadult Bonelli's eagle ("Aquila fasciata") apparently preyed upon a three-year-old male Eurasian eagle-owl in Spain. Pine martens ("Martes martes") and stone martens ("Martes foina") are opportunistic nest predators. Although martens could probably reach most eagle-owl nests due to their agility and climbing abilities, they probably will attack nests when disturbance or low food supply result in lower nest attendance by the parent owls. Cases where nests have atypically been accessible on foot (for both humans and wild predators) have resulted in Eurasian eagle-owl nests being predated. Eurasian badgers, wild boars and raccoon dogs and raccoons, the latter two both where non-native in Germany, have also reportedly preyed on nests that they can access. In coastal areas of Spain, red foxes were reported to have preyed on four eagle-owls, including one unsexed brooding adult, at nests found to be reachable on foot by researchers. Cases of red foxes killing Eurasian eagle-owls at nests have reported elsewhere albeit very rarely, normally the eagle-owl is a greater danger to the foxes (and many of its other nest predators) than vice versa. In May 2017, a red fox was filmed killing two chicks and raiding the larder of an eagle-owl in Denmark.
Eurasian woodcock
This species is the woodcock found through most of temperate and subarctic Eurasia. Northern and Asian populations migrate to southern Europe or the Indian Subcontinent, respectively. Birds in milder western European countries and on Atlantic islands are resident. The populations breeding in north-west and southern Europe are mostly sedentary. The birds' spring migration commences in February; breeding territories are reached between March and May.
The Eurasian woodcock has a large range, with an estimated Global Extent of Occurrence of 10 million square kilometres and a population of an estimated 15 million to 16 million birds. Because of its large range, stable population trend and large population size, the species has been evaluated as Least Concern. The most important threat to the population of the Eurasian woodcock in the breeding range is the increased fragmentation of its woodland habitat. At other times of year, a reduction in the amount of permanent grassland and an increase in the intensification of farming are also threats, and the species' susceptibility to avian influenza may have an impact in future.