In the 20th century, conservation groups became established and concern grew among the public over the slaying of birds for scientific purposes, as well as for use in clothes and hats. Ornithologists decided to reconsider their methods. Over time, studying birds in their natural setting without killing the bird became favoured to the “shotgun school” method.
One ornithologist who believed in this idea was Ludlow Griscom. “I started learning local birds back in 1898,” he said. “In New York City, unlike Boston, an interest in birds was not respectable. It just wasn’t done. You could hunt and shoot birds, but you couldn’t just ogle them.”
Griscom relied on field observation, and his ability to correctly identify a bird at a distance was often questioned by traditional ornithologists. Once, out in the field with an ornithologist who still believed in killing birds to identify them, Griscom identified a female Cape May warbler. To be sure, the traditional ornithologist killed the bird, which turned out to be a female Cape May warbler. After several other correct identifications by Griscom, the traditionalist was convinced that killing birds wasn’t always necessary.
Griscom’s technique of field observation was simple: “I keep a daily record book which enters the field trip, the list of birds seen, careful counts or estimates of the number of individuals of every species and sufficient notes on the weather and migration…From this it is a simple matter to draw off the data from any particular area in which I am working at the moment.”
However, even Griscom felt that sometimes killing birds to study them was okay.
“Considerable experience in the field work has convinced me that…the securing of the specimen, either for exact identification of rare stragglers of for the enrichment of the local highly educational exhibition collections of the museums properly devoted to this purpose, does (sometimes serve) to advance the interests of science.”
Both Audubon and Griscom’s influence over ornithology is best shown in Roger Tory Peterson’s work. Not only did Peterson work with Griscom, but Peterson, like Audubon, spent a lot of time drawing birds. Like Audubon and Griscom, Peterson’s love of bird watching was simply a hobby at first. “I was fascinated by birds and that set me distinctly apart,” he said, of growing up in the early 1900s.
“(Where I grew up), and throughout the nation, bird watchers were rare. They were considered kooks.”
However, it became a career for him when he compiled his information into a 1934 book, A Field Guide to the Birds. He was clear on what set him apart: “Other ornithologists…had worked out the field marks of most birds. I combined their knowledge with my visual presentation and…carried the idea through.”
Peterson’s book introduced the “Peterson Identification System.” Traditional field identification required a bird watcher to identify practically everything on the bird—from its markings and color to the size of its body, feet, wings, claws, and beak. Peterson’s system enabled bird watchers to identify birds by recognizing only a few unique physical traits. It uses field marks, which are like a bird’s fingerprints except that they are in the form of a certain color or shape of a bird’s face, wings, wing tips, tail, or body.