Fra forlagets egen omtale:
Until recently, gulls were a group that inspired dread among birders, due to the bewildering variety of plumages, age-groups, and races, many of which are very difficult indeed to separate, even to species. Things changed in 2003 with the publication of Klaus Malling Olsen’s Gulls of Europe, Asia and North America (Christopher Helm), a plate-based title that made accurate identification of gulls a realistic possibility for the first time. Gulls of the World: A Photographic Guide is a companion and successor to that seminal work.This photographic identification guide covers all of the world’s gull species, tackling some of the stiffest ID challenges in birding. Concise text places particular emphasis placed on field identification, with detailed discussion of variation, and there is coverage of habitat, status, and distribution. The text is followed by a series of high-quality photographs, carefully selected to highlight identification criteria and, crucially, to allow age and subspecific separation in the field. The species entries are complemented by an accurate colour range map.