Voices of the New World Owls, 4th edition revised.—J. W. Hardy, Ben B. Coffey, Jr., and George Reynard, revised by Terry Taylor. 1999. ARA-16, ARA Records, P.O. Box 12347, Gainesville, Florida 32604-0347, USA. $13, tape cassette.—The vocalizations of owls have always provided one of the few windows through which biologists and naturalists can study the lives of these enigmatic, nocturnal birds. Recently, vocalizations have played an important role in taxonomic studies of owls, because sibling species are often essentially alike in plumage. Despite the importance of those vocalizations to both owls and biologists alike, the study of owl vocalizations has lagged behind that of diurnal birds, in part because it is so difficult to discover which bird is making the sounds (or even if it is a bird), let alone discover the context in which the sounds are being made.
J. W. Hardy and his collaborators have been at the forefront of the study of the voices of nightbirds for over 20 years. Starting with the release of Voices of New World Nightbirds in 1980, their recordings have helped countless other ornithologists and naturalists in their studies as well. This latest recording features the songs and calls of 71 species of New World owls, a significant increase over the 46 species included on the 1980 edition of Voices of New World Nightbirds and 57 on the 1989 edition. Although some of the increase can be attributed to the tremendous amount of field work done and new recordings made in Central and South America over the last two decades, it is also the product of recent taxonomic decisions, which have created a plethora of new owl species, especially in the Otus and Glaucidium genera. The taxonomy of those genera is still in a state of flux, a condition noted several times in the text that accompanies the cassette. The authors have followed Sibley and Monroe (Distribution of Birds of the World, Yale University Press, 1990) and the American Ornithologists' Union Check-List of the Birds of North America, Seventh Edition (1998) and other recent sources for their taxonomic treatment, though in at least one case (the Northern Pygmy-Owl [Glaucidium gnoma]) they openly state their opposition to the AOU's decision not to split that taxon. The authors do create a new English name for one species, the Chocó Screech-Owl (Otus centralis).
Although I am quite a keen owl enthusiast, I do not often get the opportunity to hear Neotropical species, so it is a real treat to compare the songs of species such as the Balsas Screech-Owl (Otus seductus) with those of familiar local species such as the Western Screech-Owl (O. kennicottii), or to hear the unique descending trill of the Chocó Screech-Owl. I have used earlier editions to identify owls heard in Costa Rica and Venezuela; this is a collection of sounds largely unavailable on any other commercially produced recording. One of the welcome additions to this revision is the single-note song of the Northern Pygmy-Owl, the form heard across most of its range north of the Mexican border. This is one of the only examples of that song available on a commercial tape; other compilations have only provided the two-note song given by birds from Arizona south. There are even recordings of the type specimens of two species, the Cloud-forest (Glaucidium nubicola) and Subtropical (G. parkeri) pygmy-owls.
The text accompanying the cassette is printed on a long, narrow sheet of paper designed to be folded up into the cassette box. The print is unforgivably tiny, especially for middle-aged eyes like mine—I had to digitally scan the sheet and enlarge it to read the text for this review. I can not imagine anyone being able to read it under low-light conditions at night and most people will need a good magnifying glass to read it comfortably. That is especially serious for a text that does comment extensively on taxonomic and biological matters and will likely be cited widely. Perhaps the next edition could be accompanied by a small booklet, an obvious choice if the recording is updated to compact disc technology. The text includes a short introduction and a series of species accounts. Each of the latter includes a sentence on distribution and habitat and the location, date and recorder for each of the examples presented. I could find only one typographical error, the misspelling of guatemalae in the Chocó Screech-Owl account. Otus albogularis is announced and printed as the “White-throated Owl,” though all my references, including Monroe and Sibley (A World Checklist of Birds, Yale University Press,1993), cite it as the White-throated Screech-Owl, which is consistent will all other New World Otus.
Corrections have been made to previous editions, notably the removal of a Boreal Owl (Aegolius acadicus) song from the Northern Hawk Owl (Surnia ulula) section. There is very little room for improvement as far as the number of species covered goes, because only four species (Galapagos Barn-Owl [Tyto punctatissima], Keopcke's Screech-Owl [Otus koepckeae], Cloud-forest Screech-Owl [Otus marshalli], and Long-whiskered Owlet [Xenoglaux loweryi]) are not included in this collection simply because there are no available recordings. There is a great deal of room for improvement on the inclusion of vocalizations other than the primary song of each species. Alarm and contact calls are provided in many cases, but are mysteriously lacking in others, especially in species from North America most likely to be encountered by bird enthusiasts.
This bias towards lesser-known Neotropical owls is clear when one looks at the number of examples devoted towards each species. Most other northern species have only one or two examples of calls, but tropical species get much fuller treatment. The Tamaulipas Pygmy-Owl (Glaucidium sanchezi), for instance, a species with a rather restricted range, has five examples of primary song, all quite similar to my ear—one or two would have been quite adequate. The Snowy Owl (Nyctea scandiaca) is given only a few calls (all recorded in Sweden) and no primary song (hoots) at all. The Boreal Owl is only given one example of the primary song, although recordings of other common calls (often the calls heard most often in response to tape playback) are widely available. A similar comment could be made regarding the Northern Saw-whet Owl (Aegolius acadicus), where the contact whine call, perhaps the most often misidentified owl vocalization in North America, is not included. The Northern Hawk Owl song provided (a captive bird from Germany) is rarely heard (if ever) in North America; contact and alarm calls would have been a nice addition there. The distinctive wing claps of Long-eared (Asio otus) and Short-eared (A. flammeus) owls, though not technically vocalizations, would have been helpful as well. Although I can understand that few of the Neotropical species have recordings available elsewhere, and therefore it would be appropriate to provide as many examples as possible here, it would also have been simple to include more vocalizations of northern species. The recordings are available and there are several minutes of blank tape at the end of each side.
The tape has some shortcomings in quality as well. Many of the recordings are naturally noisy because they were made by biologists or birders under adverse conditions and are often the only recordings ever made of those vocalizations. In most cases, those background noises simply add to the ambience of exciting field biology—the squishing footsteps on the jungle floor, the cacophony of tropical insects, the chirping of frogs. Several cuts however, have annoying clicks and whirs of recording equipment, giving the tape an amateurish quality that could have easily been edited out.
After reviewing this recording, I am left with the feeling that the authors seem unclear as to what their objective is—an all-inclusive field guide to owl sounds, or a research tool for Neotropical ornithologists? The inclusion of distribution and habitat notes in the text would suggest the former, but the weight given to Neotropical species suggests the latter. I feel that with a little more care and effort,the next edition could achieve both ends, but for now most owl enthusiasts will have to put up with a limited number of different calls from their local species. The text could have also benefited from a more consistent approach to commentary on differences between species. Separating the 23 species of Otus and the 16 species of Glaucidium presented is a daunting task to the neophyte owler, and although occasional mention is made pointing out differences with similar species, that could be expanded to improve the field-guide aspect of this tape. Similarly, the fact that the song of the Unspotted Saw-whet Owl (Aegolius ridgwayi) is lower pitched than that of the Northern Saw-whet Owl could be mentioned, rather than simply say they are distinguishable.
Despite its shortcomings, this tape should be in the possession of all ornithologists and birders who are interested in the owls of the New World. Hopefully it will continue to inspire field biologists to venture out into the dark and make exciting discoveries in the mysterious world of owls. The songs and calls missing from the tape should only spur users on to make their own recordings of those vocalizations so that they might be included on upcoming editions.