1961, "April Fool Phone Calls Decline Sharply in City," New York Times, 2 Apr., p. 87.
Until noon only 251 prank calls to the Bronx Zoo had been sifted out, compared with the day-long total of 3352 on April 1, 1960. The pranksters would call Wellington 3-1500 to talk with a "Mr. Fox" (or Lyon, Bear or Wolf).