Dietary biology of the Eurasian eagle-owl
Throughout the western Mediterranean region, the Eurasian Eagle-Owl is something of a specialist on a single prey species: the European rabbit. The rabbit historically reached extremely high densities in Iberian scrub, i.e. more than 40 per every 1 square hectare (2471 square acres). In central Spain, up to 73.1% of the prey that were recorded for Eurasian eagle-owls, by number, can be rabbits. Where still available, they are also the main prey in Portugal and central France. However, following the devastation of the wild rabbit due to rabbit haemorrhagic disease, the local eagle-owls have frequently had to adapt to other, often smaller, prey. On the other hand, given the now much reduced numbers of rabbits, the eagle-owls still regularly select rabbits, seemingly out of proportion to their commonality. Although large mature wild rabbits commonly weigh , the eagle-owls usually hunt smaller specimens, often with an average weight around , with young rabbits usually selected in spring and summer and subadults selected in the autumn and winter. This is largely due to the behaviour of rabbits, with younger rabbits being forced to distribute following weaning, being less cautious in behaviour and occupying less primary habitat, thus being forced out of the confines of their burrows more regularly than mature adults. However, the estimated average weight of rabbits taken can be variable, reported from as little as in a study from Spain to as much as in the Netherlands.
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.