In search of the Ivory-billed Woodpecker.—Jerome A. Jackson. 2004. Smithsonian Books, Washington, DC. 294 pp. ISBN 1-58834-132-1. $24.95 (cloth).
Professor J. A. Jackson has been in search of the Ivory-billed Woodpecker (Campephilus principalis) from 1965 up to the present. During this period he made intermittent searches throughout the southeastern United States' range of the species, with more intensive fieldwork undertaken in the late 1980s funded by a grant from the U. S. Fish and Wildlife Service. In addition, he visited Cuba three times. These efforts resulted in two glimpses by Jackson of possible Ivory-billed Woodpeckers in flight, one in Alabama in 1973 and the other in Cuba in 1988. The current book is the first detailed report of Jackson's search efforts. In addition, the book provides results from studies of museum specimens, an overview of what is known about the ecology of the Ivory-billed Woodpecker, a discussion of the causes for its decline, biographies of naturalists who collected or studied Ivory-billed Woodpeckers, a state-by-state overview of presence of potential habitat for the species in the United States, and a record of possible sightings of the species during recent decades.
The section on the ecology of the Ivory-billed Woodpecker is, by necessity, largely a repetition of the monumental study by Tanner (1942). The studies by Jackson of museum specimens yielded interesting new findings. Notably, male Ivory-billed Woodpeckers appear to have a white spot at the base of the red crest, which is normally concealed and probably functions as a display character when the crest is fully erected. It is noted for the first time that the tail of the Ivory-billed Woodpecker is strongly curved, and Jackson proposes that the curved tail may function as an uncoiling spring that yields extra thrust to tapping, drumming, or climbing. This interesting possibility should be explored in more detail by a comparative study of tail curvature in other woodpeckers and by measuring the size and direction of the force exerted by the uncurling of the Ivory-billed Woodpecker tail.
In other sections of the book, more comparative data on other woodpecker species—especially congeners— would have been welcome. Jackson dismisses reports of drumming Ivory-billed Woodpeckers as unlikely and expects that the Ivory-billed Woodpecker uses only a double rap as method of drum communication. Although it is true that double raps are diagnostic for the genus Campephilus, several Campephilus species also perform drum series in addition to double raps. Drum series of between five and eight beats are common in Crimson-crested Woodpecker (C. melanoleucos), Crimson-bellied Woodpecker (C. haematogaster), and Guayaquil Woodpecker (C. gayaquilensis), and may actually be used more frequently than double raps in some species (Mayer 2000, Krabbe and Nilsson 2003). Therefore, it is not impossible that Ivory-billed Woodpeckers also use short drumming series, as reported by early observers. Jackson argues that the Ivory-billed Woodpecker is a social, group-living species based on an interpretation of several historical sources. I agree with this interpretation, but the argument could have been strengthened by pointing out the social tendencies in Magellanic Woodpeckers (C. magellanicus) and Imperial Woodpeckers (C. imperialis). The estimate by Tanner (1942) of a breeding period of 20 days for Ivory-billed Woodpecker is judged as improbably long by Jackson, but a breeding period of 18 to 21 days has also been found in the congeneric Magellanic Woodpecker (Ojeda 2004).
A large part of the book is devoted to the sadly failed attempts during World War II to save the mature bottomland forests in the Singer Tract of Louisiana, where J. T. Tanner had studied a small population of Ivory-billed Woodpeckers. Although the demise of the Singer Tract is lamentable, the events are not unexpected under the historic circumstances and in view of a conservation movement that was only nascent in that period. In contrast, it is incomprehensible why in 1986, after the discovery of Ivory-billed Woodpeckers in Ojito de Agua in Cuba, no floodgates of international funding and research support opened. By then, conservation organizations had unprecedented funding resources and political influence. However, despite plans to girdle trees to increase food supplies for Ivory-billed Woodpeckers, employ wardens, and establish a research station, none of these initiatives materialized. Only a three-week expedition was organized by the National Geographic Society in 1988, in which Jackson participated as scientist. Unfortunately, Jackson reveals nothing about the commercial or political interests that may have prevented conservation organizations from starting a full-scale recovery program for the emblematic bird. It was not until five to seven years after the rediscovery that privately funded individuals devoted serious fieldwork time in Ojito de Agua and other Cuban sites, only to come up empty-handed with regard to evidence of the continued presence of the species in Cuba. Jackson is in a key position to deliver an inside perspective on the riddle of the conservation failure in Ojito de Agua but does not provide any information on the subject.
The listing of potential habitat for the Ivory-billed Woodpecker in the United States makes it clear that in fact large tracts of potentially suitable habitat exist and that much of this habitat remains woefully under-explored for the species. By documenting the extent of potential habitat available, and summarizing the long list of possible sightings throughout the decades after the last confirmed sighting of the bird, Jackson illustrates that the species might still exist in the United States and that devoted searches are direly needed. The main merit of this book is to lend an academic voice to the view that the Ivory-billed Woodpecker might have slipped through the population bottleneck resulting from habitat alteration during the peak in logging activities in the swamp forests of the southern US in the early 20th century. As a tool for guiding dedicated searches, however, the book is not entirely satisfactory. It lacks maps showing areas of potential habitat and locations of reports or tables with characteristics of target search areas. Information is ordered in an alphabetic list of states rather than regions, which often transcend several state boundaries. Errors in the names and years of reports and search efforts are numerous, and often frustratingly little detail is provided about reports communicated privately to the author.
The recent sightings and video evidence of an Ivory-billed Woodpecker in Arkansas (Fitzpatrick et al. 2005) show that Jackson's optimism is justified about the possibility of the Ivory-billed Woodpecker persisting in the United States. Undoubtedly the Arkansas developments will pique the interest of many to search for Ivory-billed Woodpeckers in various areas in the United States. This book by Jackson is the best available, but not optimal, tool to help identify promising search areas.
