Cuckoos are an ancient and enigmatic avian family with a nearly global distribution. They are best known for the ∼60 species that are obligate brood parasites; however, the other species in this family are equally fascinating, exhibiting such behaviors as facultative interspecific parasitism, cooperative breeding, polygyny, and polyandry. A few cuckoos, such as the Common Cuckoo (Cuculus canorus) and Greater Roadrunner (Geococcyx californianus), are well represented in centuries of scientific literature, and in art and folklore; however, most species remain something of a mystery to us. Indeed, until fairly recently we lacked decent photographs, museum specimens, and accurate range maps for many species.
Cuckoos of the World is a welcome addition to our rather scanty list of published titles on the Cuculidae. This highly attractive and informative book is a recent entry in the Helm Identification Guides series. The key point here is that the book is an identification guide, not a field guide: it is certainly not meant to be carried around in your back pocket. This is akin to the well-known Sibley Guide to Birds (Sibley 2000), also an excellent reference source for checking your field notes and photographs or perusing at leisure in your home or office. Both books have approximately the same trim size; the hardbound version of Cuckoos of the World measures 18 × 24.5 × 3.5 cm.
Inside, Cuckoos of the World is a hybrid of The Cuckoos (Payne 2005) and Family Cuculidae (Cuckoos; Payne 1997) in Handbook of Birds of the World, vol. 4: Sandgrouse to Cuckoos, being somewhat similar in format to these two volumes, with the exception of more emphasis placed on some sections rather than others, and with the addition of hundreds of beautiful color photographs. Cuckoos of the World begins with a very brief introduction to the family, which is followed by some explanatory material (including a glossary), excellent color plates, detailed species accounts, an appendix (scientific and common names), and a lengthy bibliography.
I found the introduction rather rushed and somewhat too generalized. It may be impossible to summarize the Cuculidae effectively in only 10 pages (despite the small font size used), given the diversity of their ecology and behavior; by contrast, Payne (2005) devoted 163 pages to introductory material. Nevertheless, the authors use the little space that was allocated for this section admirably, providing some interesting examples and useful intext citations. There is also a good overview of changes to cuculid systematics in the past decades; the book generally follows the taxonomy of Payne (2005), to which it adds a further four species, bringing the family's species count to 144. This differs to some degree from many traditional check-lists that range from 129 to 149 cuckoo species.
Thirty-six color plates feature superb illustrations of all species in classic field-guide style on a white background. The drawings are superior to the overly ornate plates in Payne (2005) and are similar in quality to those in Handbook of Birds of the World. This is no surprise, because the illustrators for Cuckoos of the World also contributed artwork to that series. Each plate features illustrations for sex and age classes, and for polymorphic species as required. Adjacent to each color plate is a short account of distribution and habitat preferences, and brief identifying features for the illustrated species. Cuckoos range in size considerably, from the tiny Whiteeared Bronze Cuckoo (Chrysococcyx meyeri; 15 cm) to the gigantic Coral-billed Ground Cuckoo (Carpococcyx renauldi; 65–70 cm). It is unclear whether the drawings on each plate are to scale, but they appear to be so. The scale changes between plates, as expected; it would have been useful to have a printed scale on the bottom of each page for reference.
The bulk of the book comprises individual accounts for all species—with standard headings of Taxonomy, Field Identification, Voice, Description, Biometrics, Moult, Geographical Distribution, Habitat, Behavior, Breeding, Food, and Status and Conservation— arranged in order according to Payne (2005), based on the mtDNA studies of Sorenson and Payne (2005). This may be jarring to many readers more familiar with the substantially different, albeit traditional, taxonomic order in works such as Clements et al. (2012) and Payne (1997). In addition, some common names differ from previously published work, so I found it more useful to navigate through the accounts and color plates using the species' scientific names. A full list of scientific names and common-name equivalents used in this book is included in the appendix.
Unlike typical field guides, Cuckoos of the World has in-depth species accounts that vary in length from one to two pages of text for poorly known species such as the Red-billed Malkoha (Zanclostomus javanicus) to about six pages for species, including the Common Cuckoo, that have been studied extensively. Breeding information includes details on behavior; phenology; descriptions of eggs, chicks, and nests (where applicable); and survival. Status and conservation entries are up-to-date to 2011. In-text citations are supplied throughout. The accounts also include lengthy descriptions of the species' appearance and an almost equally long field-identification entry; this, in conjunction with the descriptive material adjacent to the plates, may be excessive given the length of the book. It might have been sufficient to distill the field identification to fewer, easily accessible key features.
Each species account contains an excellent full-color range map that uses multiple colors and shading to indicate resident, seasonal, and transient distributions. The maps are large (ranging from about 6.5 × 6.5 cm to about 8.5 × 14 cm) and easily interpreted. Unlike many other identification guides or reference books of this nature, including Payne (1997, 2005), maps in Cuckoos of the World that depict species' ranges on continents and archipelagos are expanded to the width of both text columns. This allows for considerable precision in the placement of known and hypothetical sightings according to appropriate habitat, topographical features, and so forth, rather than merely shading the entire island or region to indicate that the species does occur there. The range maps vary appreciably from some other sources, because these authors have evaluated primary distributional information rather than simply reproducing previously published range maps.
Perhaps the most remarkable feature of Cuckoos of the World is the astounding number of outstanding full-color photographs. No effort has been spared to locate and include informative photographs of every cuckoo species, even rarely seen species such as the Sumatran Ground Cuckoo (Carpococcyx viridis), Mountain Long-tailed Cuckoo (Cercococcyx montanus), and Goliath Coucal (Centropus goliath). With a few understandable exceptions, the photographs are high definition and field characters are not obscured by foliage or other obstructions. Many accounts include four or more photographs featuring polymorphic plumages, different age and sex classes, parasitic chicks with hosts, and birds at the nest and in flight or feeding. This number of high-quality photographs of cuckoos has not been assembled elsewhere, so many readers will be unfamiliar with the sizable array of plumage patterns and colors evident in this family of birds. It is a pleasure to see so many of these unusual species brought to life by their photographs, rather than merely depicted by static illustrations.
Cuckoos of the World is an excellent addition to the literature on this fascinating group of birds. Hundreds of beautiful photographs, elegant color plates, and full-color oversized range maps set this book apart from other titles of this type. If I were to recommend a single book on cuckoos to a colleague or friend—be they amateur birders or professional ornithologists—this would certainly be the one.