When you or I think of field guides, we most likely think of Peterson Field Guides. Roger Tory Peterson, the author of the series, became a birder as a child, and after years of watching and studying birds, he set out to create his own practical guide to bird identification that could be used in the field. His book Guide to the Birds was published in 1934 and was the first modern field guide.
His goal was to create a handbook with which “live birds can be run down by impressions, pattern, and distinctive marks, rather than by the anatomical differences and measurements that a collector would find useful.” The book was small, only about 7.5 inches by 5 and two hundred pages long, perfect for slipping into a back pocket or knapsack. The first run sold out in a week at $2.75 a copy. It has been in print ever since.
An entire field guide series based on the original was developed, encompassing everything from fish to the night sky. The Peterson Identification System, a feature of the series, is his practical visual method for identifying animals, plants, etc. The system is based on the idea that modern birders wanted a way to identify live birds at a distance, rather than from characteristics observed on a dead specimen, as early collectors used. Modern birders, often amateurs, were able to take advantage of new binoculars and scopes to see live animals from a distance, and his identification system was developed with this new kind of relationship to nature in mind. The system focuses on representative “field marks” that characterize each species.
Today he is considered one of the leading inspirations for the modern environmental movement.