and Other Resources on Hawk Identification and Migration
by Paul M. Roberts
can present unusual problems for field identification. How often
have you tried to identify a silent, backlit warbler half a mile
away? Let's compromise. How often have you tried to identify a
sparrow when it's only a thousand feet away from you and flying
south? How many thrushes have you seen perched or flying across
the highway while driving down Interstate 95 or I-495 at 70+ miles
an hour? How many of them have you identified? People, however,
regularly try to do that with hawks.
is, in part, why most people find that the standard birding guides
are of little help when trying to identify hawks. The basic birding
guides really help you only if you see the bird close, well enough
to appreciate color. Most hawk sightings in the field, however,
and especially in migration, entail seeing only dark gray blobs
moving quickly against a light background. If you're lucky, you
may see the silhouette of a bird soaring, and possibly pick up
patterns of light and dark contrast on the bird. Thus arose the
need for special hawk identification field guides.
first real silhouette guide to hawks was done by Roger Tory Peterson
in his first field guide, to the best of my knowledge, which is
limited to North America for this time period. Peterson used black
and white drawings of hawks almost as they would be seen when
flying directly overhead. This was a major innovation, though
the birds were not really depicted as soaring, so the silhouettes
could be misleading. Peterson, however, showed major black or
white field marks, what people were most likely to see.
next major step came with the development of the ubiquitous A
Field Guide for Hawks Seen in the North East (Hawks, 1972,
6 pp - now published by Hawk Mountain Sanctuary) The first popular
inexpensive ($1.00+) silhouette guide, it describes the flight
identification of 16 species seen in the northeast, with "side-on"
as well as ventral views of the birds in flight. The drawings
convey more field marks than Peterson's, but again are not realistic
images of the birds in powered flight or soaring.
first and only broad-based field guide to hawks is appropriately
named Field Guide to Hawks, by William S. Clark and Brian
K. Wheeler (Boston: Houghton Mifflin, Second Edition, 2001, 316
pp.). The text, by Bill Clark, is comprehensive in terms of identifying
specific field marks. The species account for Golden Eagle reveals
the basic format, divided into sections on Description, Adult,
Juvenile, Older Immatures, Similar Species; Flight; Molt, Behavior;
Status and Distribution; Fine Points; Subspecies; Etymology; and
Measurements. The book covers 47 species, including vagrants.
The detailed color plates by Brian Wheeler depict birds perched
and in flight ( flying birds from above and below), by age
set and gender where appropriate, and by race where possible.
The plates are gathered in the front of the book for easy comparison,
a page of plates facing a page of text highlighting the key field
marks of each bird in the plate.
and Wheeler is a true milestone in raptor publications. The second
edition of this book includes significant improvements on the
first. However, the first edition is a real classic and has many
different plates. I'd recommend acquiring a copy of the first
edition if you don't already have it, as well as the second edition.
in Flight by Pete Dunne, David Sibley, and Clay Sutton (Boston:
Houghton Mifflin, 1988, 254 pp.) is a whole different kettle of
fish. This classic employs Pete Dunne's prose to evoke vivid mental
images of hawks as you usually see them in flight in the field,
as dark objects in motion. It is of virtually no help in identifying
hawks perched along the highway or near your feeders.) Dunne talks
about jizz, impressions, something that Clark generally eschews.
Hawks in Flight covers 23 species, basically those seen east of
the Rockies. Excellent line drawings by David Sibley of each species
(and age or gender as appropriate) from above and below are complemented
by short summaries of key field marks. The book concludes with
76 pages of black and white photographs, most of which are apparently
Sutton's. These photos are much larger than in the Clark and Wheeler
guide, better reproduced, and much more helpful. A second edition
of this book is also in preparation. Look for it to expand its
scope and the little nuances that help identify backlit blobs
at a quarter mile.
and Wheeler show you what the birds look like, in fine detail;
when you see the birds well. They focus on often subtle field
marks to help age the bird, such as the shape or color of the
secondaries on an eagle. Dunne, Sibley and Sutton show you what
you are likely to actually see when hawks are in flight. Dunne
helps you to make a reasonable guess as to what the hawk is when
you don't see it well. If you could buy only one book, Clark and
Wheeler should be it, but anyone really interested in hawk identification
really needs both.
I say both? I meant to say "all three." In 1995 Brian Wheeler
and Bill Clark published A Photographic Guide to North American
Raptors (San Diego: Academic Press, 1995, 198 pp.). This spectacular
book contains several hundred gorgeous full-color photographs
of 43 species of North American hawks including various plumages
of each species. There are 46 photographs of Red-tailed Hawk alone!
The relatively brief text does not supplant that of the Field
Guide, it complements the earlier guide, introducing more advanced
identification guidelines for a number of species, including Red-tailed
Hawk and Golden Eagle. The book closes with a special photo section
on 14 raptor identification problems, such as "Pale Primary Panels
on Back-lighted Underwings of Flying Buteos." One could buy this
book for the photography alone.
species account includes one half to one page of text on the field
marks, often with materially supplementing the Field Guide, and
comparisons with similar species. (The operating assumption is
that you've already read The Field Guide.) There are one to four
gorgeous full-color photos per 6.5 in. x 9.75 in. page.
simply, anyone interested in hawks should have all three guides.
Each was revolutionary when it was first introduced. Each established
a new standard for American guides, and each has an updated edition
in the pipeline.
most recently published field guide to hawks, The Raptors of
Europe and The Middle East: A Handbook of Field Identification,
by Dick Forsman (London: T & AD Poyser, 1999, 589 pp.), sets a
new, higher standard for all field guides. The book covers 43
species of raptors, including 11 that have been reported in North
America. Fourteen pages are devoted to the Golden Eagle alone.
Each species section begins with a one-page overview on subspecies,
distribution, habitat, population, movements, and hunting and
prey. The identification portion starts with a summary, followed
by "In flight, distant; in flight, closer; perched; bare parts;
variation; and confusion species." That is followed by a major
section on moult, and three pages on ageing and sexing. The species
account concludes with 21 outstanding photographs, no more than
4 to an essentially 6 in. x 9 in. page. Captions focus on the
distinctive field marks evident.
by Poyser, one of the truly great publishers of ornithological
literature, this guide is a work of art, from concept, to design,
to photography, to printing. I am not sufficiently well acquainted
with European raptors to note possible subtle errors in text,
but Forsman's book has established, in my mind, a new paradigm
for any field identification guide. Although only about a dozen
of these species have been in North America, this books merits
inclusion in the library of any serious hawkwatcher. Last November,
when one or more Gyrfalcons was reported from Plum Island over
several weeks, this book was a constant reference with a 12-page
species account, and 18 spectacular photographs, of Gyrfalcon.
There are a number of hawk videos on the market, incorporating
some spectacular photography, but the best for field identification
purposes is Hawk Watch: A Video Guide to Eastern Raptors,
by Dick Walton and Greg Dodge (Brownbag Productions; 45 minutes)
This video includes field footage of 19 species of hawks likely
to be seen from Eastern hawk watches, with narration by Dick Walton.
The images are the typical dark blobs, seen at some distance,
so the field characters cited are based on many of the principles
of hawk identification espoused in Hawks in Flight. The
video comes with a brief booklet, and a humbling video quiz on
flying hawks at the end of the tape. It provides excellent training
for "real world" identification.
Watching & Migration
best basic introduction to hawk watching and migration is Hawk
Watch: A Guide for Beginners, by Pete Dunne, Debbie Keller
and Rene Kochenberger (Cape May Point, NJ: Cape May Bird Observatory,
1984. 80 pp.). Hawk Watch is an outstanding guide for beginners,
with chapters on hawk watching, diurnal raptors, equipment, how
to observe hawks, interpreting data, and submitting reports on
your observations. Excellent flight silhouettes by David Sibley
and clear text describing key field marks of each species make
easy to learn the 16 eastern species it covers. The book is not
widely available commercially, but can be obtained at some Audubon
shops or ordered directly from Cape May Bird Observatory and online
booksellers. This book was the precursor to Hawks in Flight,
developed to teach high school students. Get this downright cheap
masterpiece before it goes out of print.
Migration Watch-site Manual, edited by Keith Bildstein and
J. I. Zalles (Kempton, PA: Hawk Mountain Sanctuary Association,
1995, 177 pp.) is almost an extension to Hawk Watch. This
all-prose guide to establishing a hawk watch site was developed
to help biologists and hawk enthusiasts, particularly outside
the U.S., to study hawk migration. The guide includes chapters
on raptor migration and conservation biology, monitoring the abundance
and distribution of migrating raptors, managing data, establishing
membership programs and managing volunteer resources.
Watch: A Global Directory of Raptor Migration Sites (Cambridge,
UK and Kempton, PA USA: Hawk Mountain Sanctuary Association, 2000,
419 pp.) is the first guide to the major documented hawk migration
observation sites around the world. The book first provides overviews
of what is known about hawk migration, country by country, for
six continents, even where no regular watches are maintained.
Three hundred eighty-eight known migration sites around the world
are then described in terms of biogeography, description, land
tenure and protected status, with information on the migration
periods, raptor species seen (with peak counts an dates), and
other migrants seen. Ten sites are described in detail for Massachusetts.
Our own Wachusett Mountain is one of only 106 sites described
worldwide, only three in New England, that average in excess of
10,000 hawks annually. Information is included on the migratory
status of all hawks and the threats they face.
essence, Raptor Watch is a detailed description of what's
known about hawk migration sites that are vital to understanding
what is happening to raptor populations worldwide. This book is
not directed to the beginning hawkwatcher, but to those who regularly
hawkwatch or individuals who would like to hawkwatch in other
states or foreign lands.
most recent book on hawkwatching is Hawkwatching in the Americas,
edited by Keith Bildstein and Daniel Klem Jr. (Kempton, PA: Hawk
Migration Association of North America, 2001, 277 pp.). This book
consists of peer-reviewed papers presented at the 25th anniversary
meeting of the Hawk Migration Association North America (HMANA)
in June 2000. Intended primarily for the experienced hawkwatcher,
it should be of interest to anyone with an interest in bird migration
per se, with major papers on full season hawk watches in coastal
Texas, raptor migration through Mesoamerica (Veracruz) , ageing
eagles at hawk watches, and using Doppler weather radar to study
hawk migration. Raptor Migration in Israel and the Middle East
by H. Shirihai, R. Yosef, D. Alon, G.M. Kiwan, and R. Spaar. (Eilat,
Israel: International Birding and Research Center, 2000, 191 pp.),
documents what can be learned via hawk migration counts. This
ground-breaking , well-produced book includes a history of the
raptor counting effort in the Middle East, with chapters on migration
routes and numbers, monitoring palearctic raptor populations,
conservation, flight behavior of migrating raptors in Israel,
and more. The core of the book is species accounts of 43 species
of palearctic raptors. Since only 5 Golden Eagles have been recorded
as migrants in the Middle East, that species account is only a
page and half long, with data on the European population. Seven
pages are devoted to the much more abundant Steppe Eagle (Aquila
nipalensis), which includes peak seasonal counts and locations
for autumn and spring, migration phenology at Eilat, population
trends, and 51 superb photographs. This book will be of interest
primarily to serious students of hawk migration and conservation,
or those thinking of traveling to Israel, one of the premier birding
spots in the world during migration. The book demonstrates clearly
the value of long-term hawk migration counts.
Two books focus on hawk flight in migration. Bill Welch's Hawks
at My Wingtip (Thorndike, Maine: North Country Press, 1987
148 pp.), is a non-technical description of innovative work that
Welch performed with the New England Hawk Watch, using powered
gliders to study hawk migration. The low-key book is loaded with
small pearls of information on such topics as the distance at
which one can see hawks; the altitude at which hawks migrate throughout
New England, and the general speed and direction of their flight.
This very inexpensive, unpretentious book is still available through
some online booksellers, and may be available through some stores.
a more thorough, technical analysis of hawk flight in migration,
it is essential to turn to Flight Strategies of Migrating Hawks
by Paul Kerlinger. (Chicago: University of Chicago Press, 1989,
375 pp.) Not written for the beginning hawk watcher, Flight
Strategies is an advanced analysis of specific aspects of
migration, supported with formulas, statistics, and graphs. Topics
include ecology and geography of hawk migration; methods of studying
migrating hawk; structure of the atmosphere, flight mechanics:
theory, flight mechanics: empirical research; flight direction,
altitude and visibility of migrants, selection of flight speed,
and daily flight distance. It is a motherlode of information.
I have read this book more times than any other book I've ever
owned, and am still gaining new insights into it year after year.
Technically out of print, this classic is still available. I would
put it in the mandatory category for anyone seriously interested
in the migration of hawks or any other birds. (I should mention
that I reviewed this manuscript at different stages of development.)
At times the book is very dense reading, leaving one to yearn
for a "Cliffs Notes" version for the beginning hawk watcher, but
it is more than worth the effort at times required of the reader.
It is an intellectual artichoke for the hawk watcher, to be peeled
piece by piece and carefully savored.
are an increasing number of books on specific raptors, one of
which is reviewed elsewhere in this issue.. Two broad-based reference
works are worthy of special note. Birds of Prey edited
by Ian Newton, (New York: Facts on File, 1990, 240 pp.) is an
impressive introduction to birds of prey, excluding owls. It includes
chapters on "What is a Raptor," "Kinds of Raptors," "How Raptors
are Studied," "Habitats and Populations," "Feeding Habits," "Social
Behavior," "Reproduction," " Mortality" and an excellent overview
of migration and movement by Bill Clark. The book closes with
three essays on hawks' relations with humans. Top experts have
written each chapter and numerous fascinating sidebars in very
readable prose. Laid out like a "coffee-table" book , it is filled
with spectacular color photographs and is easy to read. No other
book conveys a better understanding or appreciation of hawks for
the average person.
much more detailed natural history of hawks is available in Handbook
of North American Birds, Volumes 4 & 5, Diurnal Raptors, Parts
1 & 2, edited by Ralph Palmer (New Haven: Yale University Press,
1988, 433 pp. & 465 pp respectively) If you want to learn more
about the life history of a particular species, this is the place
to start. These encyclopedic volumes, which include only a few
black and white illustrations, provide the best, most complete
and most recent "natural histories" or species accounts, of North
America's hawks generally available.
final major source of information on our hawks is The Birds
of North America: (Philadelphia, PA and Washington, D.C.:
Academy of Natural Sciences and The American Ornithologists' Union,
ongoing; typically 20-28 pp. each). This series of individual
life history accounts for all North American avian species is
not yet complete. Excellent accounts of Broad-winged Hawk, Red-shouldered
Hawk, Red-tailed Hawk, Northern Harrier, Cooper's Hawk, and Merlin
are currently available, along with some primarily western species.
Written to a standard format, the accounts cover: distinguishing
characteristics, distribution, systematics, migration, habitat,
food habits, sounds, behavior, breeding, demography and populations,
conservation and management, appearance, and measurements. These
individual species accounts can be ordered through Buteo Books
www.buteobooks.com). Many raptor species accounts are still in
the aid of at least several of these resources, you should be
able to add considerable knowledge and enjoyment to your hawk
watching, or even 'just" regular birding.
article appeared in
Observer, Vol. 29, No. 4, 2001.