Reg Foggerdy disappeared last week while pursuing a feral camel in a remote area of Western Australia state.
Police trackers found him sitting under a tree on Tuesday morning around 15km (9 miles) from where he became lost.
He was discovered “extremely dehydrated, a bit delusional, but he’s received treatment, first aid on the ground, and it’s fair to say he’s now sitting up and talking,” Police Supt Andy Greatwood told ABC radio.
Supt Greatwood also praised Mr Foggerdy’s “fantastic” skills, saying that while more details of how he coped were likely to emerge, “most people would not have survived”.
“The amazing news is his last couple of days of survival were achieved by lying down under a tree and eating black ants, so that’s the level of survival that Mr Foggerdy has gone to,” he said.