The Peterson Field Guides (PFG) are a popular and influential series of American field guides intended to assist the layman in identification of birds, plants, insects and other natural phenomena. The series was created and edited by renowned ornithologist Roger Tory Peterson (1908–1996). His inaugural volume was the classic 1934 book A Field Guide to the Birds, published (as were all subsequent volumes) by the Houghton Mifflin Company.
The PFG series utilized what became known as the Peterson Identification System, a practical method for field identification which highlights readily noticed visual features rather than focusing on the technical features of interest to scientists. The series both reflected and contributed to awareness of the emerging environmental movement.
Most books in this series use a section of plates of drawings (usually reduced from commissioned paintings) rather than photographs of the subject species, grouped at the center of the book. This allows for idealized portraits that highlight the identifying "field marks" of each species; such field marks are often indicated by arrows or straight lines in the plate illustrations. However, in several books in this series, the plates consist of photographs (usually without such arrows or indicators), such as in the guides for the atmosphere, coral reefs, rocks and minerals, and the (old Charles Covell 1984 guide to) Eastern moths. In many books in this series (especially older editions), a number of the plates are in black and white. For examples, older editions of the Eastern reptiles/amphibians book had many black and white plates which were colorized for the current edition,[1] and the original 1934 Eastern bird book had only 4 color plates.[2] At least one book (insects) was entirely in black and white. However, most newer editions are often full-color (or almost full-color) and tend to be larger. One source claims that the increased size of one of the new editions (Eastern reptiles/amphibians) was considered detrimental to its use as a field guide by its own author and was a publisher decision.[3]
In some cases, new "editions" in this series are entirely new books with completely new texts and illustrations. For example, the fourth edition of the mammals guide has an entirely new text and illustrations by new author Fiona Reid, because the author (William Burt) and illustrator (Richard Grossenheider) of previous editions are both deceased. In fact, Grossenheider died prior to the publication of the previous third edition of 1976.[4] Also, the current Northeastern moths guide by David Beadle and Seabrooke Leckie is an entirely new book than the out-of-print 1984 Eastern moths guide by Charles Covell.[5] The Beadle/Leckie book covers a smaller geographical area and (one author claims) covers moths in greater detail.[5] The old Covell book has been out-of-print for many years, but is currently available through the Virginia Museum of Natural History (which purchased the rights to that book).[5][6]
The above situation of an old "edition" persisting alongside its intended replacement edition is not unique to the Eastern moths guide. George Petrides' 1988 Eastern trees book (PFG11B) was originally intended to replace Petrides' own 1958 Eastern tree and shrubs (PFG11A) book. However, both books remain popular and the original publisher still offers both books for sale (unlike the case of the old Eastern moths book).[7]
Differences between editions can serve to indicate changes in scientific perspective as well as changes species distribution. For example, the second edition of the freshwater fishes guide by Page and Burr (2011), published 20 years after the first edition, increased the number of species included from 768 to 909, largely due to the addition of previously unrecognized species (114), as well as increased numbers of newly established exotic species (16).[8] It also expanded coverage of marine fish commonly found in freshwater (19).