He produced his first book on the birds of eastern North America in 1934. Entitled A Field Guide to the Birds, it was a sensation. His meticulously drawn birds, each with an arrow indicating its main feature for identification, together with a concise description of where it was to be found and its general characteristics, revolutionised bird-watching. Its effect upon professional ornithologists and amateur bird watchers alike was instantaneous, enabling them for the first time reliably to identify birds in the field.
This was followed by A Field Guide to Western Birds (1941) and then in 1954, after three years' extensive travel in Europe together with two distinguished British ornithologists, Guy Mountfort and Philip Hollom, Peterson produced The Birds of Britain and Europe,which was published by Billy Collins. Their collaboration dated from 1949 when Peterson met Mountfort on Hawk Mountain in Pennsylvania, where ornithologists gather to watch the spectacular migration of birds of prey. Within a few minutes they had decided to go into partnership; Hollom had been planning a similar book, so the three of them decided to join forces.
No less than nine impressions of The Birds of Britain and Europe were published in the next nine years, and revised and improved editions have been published ever since; it has also been translated into 14 languages. Peterson's pioneer work has been copied and followed by literally hundreds of different field guides covering every facet of natural history.
Peterson was born in upstate New York of a Swedish father and a German mother. He looked at birds from an early age and took his first bird walk on 8 April 1920. He was a rebellious boy who slept in class, and was known as "sleeping Jesus" - the trait persisted; decades later, Mountfort teasingly referred to him as "sleeping Peterson" when they travelled together.
Peterson studied art at the Student Arts League (1927-28) and the National Academy of Design (1929-31), which he paid for by decorating chinese lacquer with butterflies, flowers and birds. He went on to teach for a few years before in 1934 becoming the art editor of the Audubon Society, where he remained till 1943.
From the early 1950s until he died he was editor of the Houghton Mifflin field guide series, which embraced a wide spectrum of natural-history subjects, from birds, birdsong, shells and butterflies to ferns, animal tracks and amphibians. He was art director of the National Wildlife Federation in the United States from 1946 to 1975 and Vice-President of the Society of Wildlife Art of Great Britain from the mid-Fifties.
Roger Peterson had the rare quality of inspiring others with his enthusiasm. It was said that he could recognise every species of bird in North America and most in Europe and Africa not only by sight but by sound as well.
When I was walking with him through a wood in Buckinghamshire once, a small brown bird flitted furtively through the undergrowth. "Would that be a nightingale, James?" he asked. It was. He had never seen one before, but he recognised it immediately.
He had a somewhat one-track mind. When he was "birding" nothing distracted him. The story is told of his arrival in Seville with members of the Mountfort expedition on its way to visit the Coto Donana. As the distinguished group of ornithologists, which included Viscount Alanbrooke and Sir Julian Huxley, gazed up in admiration at the great cathedral he was heard to pronounce: "There are lesser kestrels nesting in the roof."
His early wealth - for he soon became the first millionaire author of bird books - bemused him. Staying with his great friend the sea-bird expert James Fisher, with whom he wrote the classic Wild America (1955, on the wild areas in the US), he asked Fisher if he should invest the large sums which were beginning to pile up in his bank account. "What are stocks and shares?" he asked. "Should I buy some?"
Throughout his life he devoted himself to matters of conservation and in helping his numerous friends he had made all over the world. When I went to him for help and advice over my hesitant plans to write The Herons of the World, he said. "Of course you are best person to write it. You have seen more herons than anybody else, haven't you?" Not only that but he generously wrote the foreword.
He received many honours including the Brewster Medal of the American Ornithologists Union, the Gold Medal of the New York Zoological Society, the Gold Medal of the National Audubon Society, and he was the first American to receive the Gold Medal of the Worldwide Fund for Nature (WWF).
Roger Peterson supported wildlife and conservation bodies all over the world, and his presence at dedication or fund-raising events ensured that huge crowds would attend.
In October last year he was due to attend the celebration of the 50th anniversary of the J.N. "Ding" Darling National Wildlife Refuge, which was thought to be under threat from property developers in Florida, when he suffered a mild stroke. Sadly he never recovered.
His name will rank with those other two giants of ornithology - John James Audubon and John Gould.
Roger Tory Peterson, ornithologist: born Jamestown, New York 28 August 1908; married 1936 Mildred Washington (marriage dissolved 1942), 1943 Barbara Coulter (two children; marriage dissolved 1976), 1976 Virginia Westervelt; died Old Lyme, Connecticut 28 July 1996.Reuse content