If you are serious about tracking, you will want to acquire a library. Here is a list of good tracking guides and other references. Each one has a particular strength--a reason to find its way to your bookshelf. These citations are not intended as replacements for "dirt time" but will help you make the most of your time in the field.
Wildlife of the Pacific Northwest. David Moskowitz (2010, Timber Press)
This fairly recent book is now my companion when traveling in the Northwest. It is small enough to carry in the field but includes enough information about each species to be really useful. In addition to the tracks of all the Northwest mammals it also covers many common birds, reptiles, amphibians and invertebrates. There are range maps for most species, a key to tracks, and photos showing other sign. If you had to pick one book for the Northwest, this would be a perfect choice.
Tracking and the Art of Seeing. Paul Rezendes (1999, Firefly Books) This is one of the best tracking book on the market. I learned more about tracking from this book than any other source. Rezendes combines his skill as a photographer with his keen insights about each animal's habits, tracks, and sign. The attention given to all manner of sign distinguishes this from field guides that cover primarily tracks. The appendix has a unique set of charts showing the typical ranges of track and gait measurements. This book is an absolute must for every tracker. Note, however, that this is a book to read before you go into the field, it is not really a field guide. Scats and Tracks of the Pacific Northwest James Halfpenny (1999, Falcon Publishing) Excellent little field guide covering birds and amphibians as well as mammals. Other books in this series focus on the southwest and east coast. Halfpenny is THE expert on gaits so that is a particular strength of this book. Also look for his classic A Field Guide to Mammal Tracking in North America. Animal Tracks of Washington and Oregon Ian Sheldon (1997, Lone Pine Publishing) Another good pocket sized field guide covering birds and amphibians as well as mammals. This series includes books that cover other regions. I particularly like Sheldon's use of ranges rather than averages for track measurements. For some unkown reason, the mink was omitted (perhaps a printing error). Mammal Tracks and Sign Mark Elbroch (2003, Stackpole Books)This volumne is most comprehensive guide for mammal sign currently available. Elbroch has extensive photos of the tracks of countless species, including many small mammals. Although living in New England, Elbroch provides good coverage for all regions of North American. I got my copy just before a trip down the Grand Canyon of the Colorado River and was impressed with the scope of coverage for bighorn, ringtail, white-tailed antelope ground squirrels, and other species of that area. Like his bird track book, he provides extensive treatment of many types of sign, rather then limit the presentation to just tracks. The 30+ page treatment of gaits is another unique feature of this book. At nearly 800 pages, though, this is a reference for advanced trackers, not a beginner book or a field guide.
A Field Guide to Animal Tracks Olaus Murie (1954, Peterson Field Guide Series, Houghton Mifflin) This is the first serious book on tracking and was until recently the most comprehensive. Murie traveled extensively throughout the continent (even down into Central America) to research this book. Modern authors have borrowed from this guide or used the Murie collection in writing their own book. Even with all the new guides on the market, this one deserves a place on your shelf. Bird Tracks and Sign Mark Elbroch (2001, Stackpole Books)An excellent and comprehensive guide to bird tracks and sign--and the first North American guide to give more than a cursory treatment. Elbroch has extensive photos and drawings of the tracks of countless species but then goes on to cover scat, pellets, tree sign, skulls, kills, and feathers. Elbroch is a friend and collaborator of Rezendes and the association shows. (My only complaint is that I found the organization by track size a bit hard to use. I would have preferred tracks presented by family with an appendix sorted by size.)
A Field Guide to Tracking Animals in Snow Louise Forrest (1988, Stackpole Books)If you ever track in the snow then you must buy this book. Forrest helps you focus on gaits with realistic drawings of tracks as they appear in snow rather than the stylized perfect prints shown in most guides. The text is terse but extremely helpful. At first glance I thought this book simply duplicated what I already had in other books but upon closer inspection I realized there was more to it. Reading this one reoriented my thinking to the unique aspects of snow tracking and helped me reap much more from my time in the field.
Desert HolesThis unique little book is dedicated to holes -- the holes desert creatures make to escape the heat of the day and to have their young. While oriented toward hole makers living in the Sonoran Desert around Tuscon, Arizona, the book has utility for other Western states.
My philosophy is the more you know about the animal you are tracking, the better tracker you will be. If you have any doubts, watch a bow hunter. He has to know the animal’s habits well to get close enough to get off a shot. Or you could take a walk with Steve Engle, a local naturalist. When you encounter an unusual track, Steve is always several steps ahead of everyone else in solving the mystery, drawing on his exhaustive knowledge of the habits, distribution, and life cycle of bird or beast. In that spirit, I would like to mention some books that I have found helpful in my quest to learn more about the natural world of the Pacific Northwest.
Mammals of the Oregon and Washington Tamara Eder (2002, Lone Pine Press)
This new field guide provides a nice overview of the mammals of our region. The text covers the description, distribution, habitat, feeding, dens, and young of each species. The coverage is limited to just two states but the expanded narrative compared to other field guides is quite worthwhile.
Mammals of the Pacific Northwest Chris Maser (1998, Oregon State University Press) I have examined several books on the natural history of mammals but found this the most informative and readable. The book focuses on western Oregon but would still be a useful reference in anywhere in our region. Maser devotes several pages to each species, covering feeding habits, reproduction, life cycle, and other details. The treatment of small mammals, which many books gloss over, is particularly strong. I would not call this a tracking book, but Maser does include photos of tracks and other sign. To me this is much more than a reference book as I found it very fascinating reading. This is a must for your library. Land Mammals of Oregon B.J. Verts and Leslie Carraway (1998, University of California Press) This is the ultimate technical reference for mammals of Oregon and neighboring states. Look to this massive work for careful documentation of the distribution, diet, reproduction, and habits of the mammals of our region. Range maps, skull diagrams, and informative syntheses of the available research on each species distinguish this work. The list price is steep ($80), but inexpensive (~$25) new or used copies are available from discount book outlets.Mammals of the Pacific States Lloyd Ingles (1965, Stanford University Press)
Although somewhat dated, this technical reference has more detail about identifying each species and range maps for California, Oregon, and Washington.
Amphibians of Oregon, Washington, and British Columbia Corkran and Thoms (Lone Pine, 1996).
I know a bit about mammals and birds but my first salamander tracks had me baffled until I found this book. This comprehensive identification guide examines the entire life cycle of the toads, frogs, and salamanders in the Pacific Northwest. The authors provide information about the typical habitat during each stage of the life cycle as well as range maps. Of particular interest for trackers are the drawings of feet for different species. I would have liked information on feeding habits and other behavior, but that is beyond the scope of what the authors attempted.
Sibley’s Guide to Bird Life and Behavior Elphick, Dunning, and Sibley (Eds) (Alfred A. Knopf, 2001) This extensive volume gives succinct descriptions of the anatomy, taxonomy, feeding behavior, and reproduction of each family of birds in North America and beyond. Trackers will appreciate the drawings of feet for representative species (but unfortunately there are no measurements). Do not buy this book until you are already familiar with your local birds—start with a good identification book instead. For more detail about the behavior of a few common species check out the bird behavior books by the Donald Stokes. Plants of the Pacific Northwest Coast Pojar and MacKinnon (Lone Pine, 1994) OK, so this book is not about animals. Participating in various census projects, though, I have learned the importance of being able to describe the environment in which the target species lives. And sometimes I just stop to smell the wildflowers. This identification guide covers plant families from mosses to trees as well as flowers. Those interested in primitive arts will appreciate the descriptions of traditional uses provided for some plants.