Rooks, ravens and relations - BirdGuides

A comprehensive genetic analysis of all the recognised species and many subspecies of the cosmopolitan crow genus Corvus has been performed with some surprising results.

Details : Rook - BirdGuides

Crows: Everything you need to know about the whole corvid family

Identification of Juvenile Rooks and Carrion Crows - Corvid Isle

Details : Raven - BirdGuides

Rook - eBird

Identification of Juvenile Rooks and Carrion Crows - Corvid Isle

British crow family guide: identification, habitat and species

Rook Bird Facts (Corvus frugilegus)

Identify a Rook, Corvus frugilegus

Rook (bird) - Wikipedia

Plate 60 - Jackdaws, Rooks, Crows and Ravens - A Field Guide to