Rook

The rook (Corvus frugilegus) is a member of the family Corvidae in the passerine order of birds. It is found in the Palearctic, its range extending from Scandinavia and western Europe to eastern Siberia. It is a large, gregarious, black-feathered bird, distinguished from similar species by the whitish featherless area on the face. Rooks nest collectively in the tops of tall trees, often close to farms or villages; the groups of nests are known as rookeries. Rooks are mainly resident birds, but the northernmost populations may migrate southwards to avoid the harshest winter conditions. The birds form flocks in winter, often in the company of other Corvus species or jackdaws. Wikipedia →

5–10% of wildlife watchers report a Rook sighting in Tatra National Park, based on 46 days of visitor records from GBIF citizen-science data.