accidently, i found this while reading about birds and the 'big year'
The wide publication in 1934 of the first modern field guide by Roger Tory Peterson truly revolutionized birding. However, in that era, most birders did not travel widely. The earliest known continent wide Big Year record was compiled by Guy Emerson, a traveling businessman, who timed his business trips to coincide with the best birding seasons for different areas in North America. His best year was in 1939 when he saw 497 species. In 1952, Emerson's record was broken by Bob Smart, who saw 510 species