"Barney was by my side during our eight years in the White House," Bush said. "He never discussed politics and was always a faithful friend. Laura and I will miss our pal."
With public access to the White House more restricted in the aftermath of 9/11, first lady Laura Bush sent Barney out to prowl the building with the camera. Barney Cam's 4.5-minute video tour of the mansion decorations was such a hit that his movies became an annual feature for the rest of Bush's presidency.
Later videos later included Miss Beazley, the Bush family's other Scottish terrier, and even high-profile guests including cameos by country singer Alan Jackson and former British Prime Minister Tony Blair.
A burial is planned at the former president's ranch in Central Texas, where Bush says Barney, "a fierce armadillo hunter," loved to accompany him while fishing for bass.
Barney politely greeted heads of state, queens and prime ministers but "guarded the South Lawn entrance of the White House as if he were a Secret Service agent," Bush added.
Barney was the continuation of a Bush family tradition of presidential dogs begun by Millie, the springer spaniel brought to the White House by President George H.W. Bush and his first lady Barbara Bush.