We (the authors, TE and CH) started banding raptors in the mid-2000s and mid-1980s, respectively, by working with experienced banders at raptor migration sites in the western United States. During this time, and up until recently, printed resources available in the blind typically consisted of the raptor age-sex keys from the United States Bird Banding Laboratory (US Department of the Interior and Canada Department of the Environment 1972), a slimmed-down version of expected measurements for each raptor species and sex, and the Peterson Field Guide to Hawks (Clark and Wheeler 1987). The Pyle Guide Part II (Pyle 2008) was introduced in the mid-2000s, but to us, this system of aging and sexing raptors seemed slow to gain momentum within the raptor banding community. Back then TE remembers raptor researchers suggesting that Pyle (2008) was more complicated than it needed to be and that there were simpler ways to age raptors. So instead, we continued to use the best tools we had to learn about aging, sexing, and molt: raptor study skins, photographs, and experience in the field.
We were excited to hear that HawkWatch International's In-hand Guide to Diurnal North American Raptors had come into fruition, as it brings decades of experience and knowledge, appropriate raptor terminology, high-quality photos, and other useful information together in one guide.
The In-hand Guide to Diurnal North American Raptors is laid out like a standard field guide, with an introduction that includes a “How to Use” section, a glossary, and sections on anatomy and age-class systems. The authors also include a section on how to document raptors of all sizes using photography, contemporary information on molt, and an introduction to using fault bars and aberrant plumages. There are brief sections on hybrid raptors, basic raptor banding guidelines, and then the guide immediately jumps into raptor identification, starting with Accipiter through Falco. Although this guide covers seventeen species of North American raptors, it does not include species from the southwestern and southeastern regions of the USA, or Mexico. Species like the Harris's Hawk (Parabuteo unicinctus), Gray Hawk (Buteo plagiatus), Zone-tailed Hawk (B. albonotatus), Short-tailed Hawk (B. brachyurus), Aplomado Falcon (Falco femoralis), Crested Caracara (Caracara cheriway), and Osprey (Pandion haliaetus) are not included in this guide.
Each species profile starts with a single-page introduction about plumage characteristics, standard measurements, and a comparison of juvenile and adult photos, or photos showcasing the different morphs of a species. This is followed by a series of large photos for identification: HY/ SY and adult photos (light, intermediate, dark morphs as available), then specifics on SY/TY, AHY/ASY, ASY/ATY. For certain species, including Red-tailed Hawks (B. jamaicensis), Merlins (F. columbarius), and Peregrine Falcons (F. peregrinus), the authors document and provide identifying information for the different subspecies. For Bald Eagle (Haliaeetus leucocephalus) and Golden Eagle (Aquila chrysaetos), the authors present extra pages of detailed photos dedicated to accurately age both species.
The guide emphasizes the value of photo-documenting birds in-hand and explains why it is important to capture certain feather details in a photograph. Correctly posing a bird for molt documentation will relieve future headaches and debates when banders need to go back to the photo to justify a reported age. This guide is laid out with ample and diverse photographs of raptors in-hand to show how to correctly spread wings for photos highlighting molt sequences. The authors label the primary and secondary feathers well, so the reader can easily follow along with the photo descriptions. The detailed images of the birds' heads complement and complete each species profile.
The guide presents photographs that show key traits that have not been previously available in the resource materials usually found in a field blind, for example, photos that show retained HY and AHY rump feathers of Accipiters, unknown-age upperwing feathers on Merlins, and multiple forms of Harlan's Hawk (B. j. harlani) tails.
One cutting-edge topic included is a discussion showing that juvenile and adult female American Kestrels (F. sparverius) should not be aged by the width of the subterminal tail band. The authors provide photographic evidence that juvenile female kestrels can have a significantly wider subterminal black tail band compared to the other tail bands, similar to adult female kestrels. Many raptor banders have used the seminal paper by Smallwood (1989) for decades as a guide to ageing female kestrels in hand. The In-hand Guide to Diurnal North American Raptors shows that as more American Kestrels have been banded over time, researchers have learned more about kestrel plumage and ageing, and the use of subterminal tail band width as a key diagnostic tool may not be reliable. The case of the kestrel tail band demonstrates how our knowledge about raptor ageing and sexing changes with time and experience, and that it is beneficial for raptor researchers to have constructive discussions about the techniques that we have used in the past, and to be open to new methods to collect more accurate data.
The stated purpose of this guide is to illustrate age, sex, and species/subspecies of commonly captured North American diurnal raptors by using high-quality photographs. Additionally, it briefly covers the basics of banding techniques. During our review, we found that HawkWatch International's In-hand Guide to Diurnal North American Raptors is a comprehensive and thought-provoking photo guide that will help many raptor banders of all experience levels who work with post-fledging raptors. The authors put in a lot of time to gather photos from many raptor researchers, and we acknowledge the hard work that has gone into accomplishing this task. However, we found the banding techniques portion falls short when compared to the other sections of the guide. It could be removed, and replaced with a reference to The North American Banders' Manual for Raptor Banding Techniques (Hull and Bloom 2001). Or perhaps it could be lengthened to include, for example: reasons to not band a hawk, why not to weigh a bird with a full crop, pros and cons of examining molt, or how to take photos in different lighting. We understand that adding additional techniques to this section would make the guide longer and we emphasize that this section should not be a replacement for hard-earned, hands-on experience in the field with experienced mentors.
We have mixed feelings on whether we would bring this beautiful guide to the trapping blind. It is a great resource, but it feels like a guide that one would take time to study, rather than pull off the shelf of the blind to use on a busy banding day; CH would bring it to the blind but would have a backup copy safe at the office. If banders need to flip to a certain species quickly in the field, they must be familiar with where the species are in the guide and how it is laid out. It would be helpful if there were tabs for each species. It is a bit bulky, but for good reason.
Banders using this in a trapping blind may want to be cautious and find a way to protect it from the elements. Leaving it out on a processing table would result in damage after a rainy or snowy day. However, for road-trapping or other field work, it would be easy enough to carry around. Possibly, future editions will be hard-bound, which would add to its field durability.
The In-hand Guide to Diurnal North American Raptors is truly a monumental achievement and every North American raptor bander should have it in their library. Even non-banders, researchers, photographers, birders, falconers, and interested laypeople will benefit by reading it. Although we recommend this to any beginning raptor bander or handler and would urge anyone we mentor in banding to read this before field work, this guide is geared for the more experienced raptor bander. The heavy detail on molt and the lightness of the banding section presume that the reader has ample experience in the field. We believe that for many years to come there will be dog-eared copies of this guide in raptor banding blinds, on back seats and in dusty camper shells, and lodged in the field bags of many experienced and soon-to-be-experienced banders in North America and elsewhere. The authors were able to gather excellent in-hand photos of each species, pull together detailed information on molt, and bring it all together in one place—something many banders have been wanting for decades. This book will advance raptor banders' knowledge, and serve as a positive precedent for our fellow banders on other continents.
