Late "Crocodile Hunter" Steve Irwin concealed pain and suffering behind his enthusiastic public persona, his father said in an interview broadcast Monday. In the Australian Broadcasting Corp. interview, Bob Irwin, 68, said audiences failed to realize how much pain his khaki-clad son masked during his public performances. He gave no details of the reasons for his son's private suffering.

"People don't realize just how much he gave of himself," his father said. "He was always very good in front of the media, and a lot of the pain and the suffering didn't show through."

Last month, Bob Irwin left Australia Zoo, which he founded 36 years ago in Australia's northeastern Queensland state, amid rumors that he had fallen out with his son's American widow, Terri.

He did little to squash those rumors, saying that he was leaving the family run zoo because he had become a "disruptive influence." He said "the problem I had was that the management and I didn't agree on certain aspects of Australia Zoo after Steve's passing."

Zoo director Wes Mannion, a close friend of Steve Irwin, said "it's not a rift."

"Bob has decided to go his different way," Mannion told ABC.

Steve Irwin is buried at a secret location on the property.

Terri Irwin has tried to dampen speculation that her father-in-law left because he disagreed with way his son's legacy was being handled.

Bob Irwin could not be immediately contacted for comment on Monday.