Puppeteer Jerry Nelson is shown with "Sesame Street" characters Herry Monster, right, and Count von Count. (Gil Vaknin/AP)

Jerry Nelson, the puppeteer behind a delightful menagerie of characters including Count von Count on “Sesame Street” and Gobo Fraggle on “Fraggle Rock,” died Aug. 23 at his home on Cape Cod, Mass. He was 78.

The Sesame Workshop confirmed the death and said Mr. Nelson had emphysema.

In a tribute posted online by the nonprofit Sesame Workshop, Mr. Nelson was lauded for his artistry and the “laughter he brought to children worldwide” with the Count and other Muppet puppets including Sherlock Hemlock, Herry Monster and the Amazing Mumford.

Mr. Nelson was part of other projects featuring Jim Henson’s Muppets, including the 1984 movie “The Muppets Take Manhattan” and TV series including the 1980s “Fraggle Rock” and 1990s “Muppets Tonight.”

In recent years, Mr. Nelson gave up the physically demanding job of operating the Count and other puppets on “Sesame Street” but still voiced the characters, the workshop said. The show’s new season launches in September, and Mr. Nelson’s voice will be heard.

In 2010, he released the album “Truro Daydreams,” with the title referring to the Massachusetts town.

Jerry Nelson was born July 10, 1934, in Tulsa and raised in Washington, D.C. He worked as a puppeteer with Bil Baird before starting his association with Henson in the mid-1960s on “The Jimmy Dean Show,” a variety program that featured the Muppets.

Survivors include his wife, Jan.