Speaking on the anniversary of Hall of Fame pitcher Randy Johnson hitting a bird with a pitch back in 2001, Michael Wunder, Associate Professor of Integrative Biology, did the math: "There are 30 teams, so about 700,000 pitches per year, just for the majors.

If we consider the minors, then that’s about another three to four times as many pitches. This has only happened two times in my memory [once in the majors, once in the minors]. So the probability is like one in 50 million or so over the past 20 years."

Bird Experts Reflect On Randy Johnson Hitting A Bird With A Pitch
Newsweek, Mar 24