Since the first competition, the World Series has been held annually on a date between May 9 and May 19, which coincides with the height of the spring bird migration through New Jersey. Winning tallies have ranged from a low of 182 species in 1985 to a high of 231 species in 2003 for the team sponsored by Nikon Sport Optics and the Delaware Valley Ornithological Club (DVOC). The event has steadily gained in popularity over the years; in 1984, 13 teams took part, compared with over 60 in 2006. Over the years, the World Series of Birding has raised more than $9,000,000 for bird conservation.