As the bush doof party clock ticked past its 33rd hour, no one seemed to notice Rob Fairchild vanish into the cold night.

A day-and-a-half of dancing, drug ingestion and the endless drone of trance music had left the 400-plus revellers too high or tired to realise one of their own - part of the doof "tribe" - had wandered off.

Many arrived at dusk on Friday stocked with enough food, drugs and good vibes to last the three-day festival.

LOST REVELLER THOUGHT HE WAS GOING TO DIE

The directions to the makeshift party grounds, about 6km off Brookton Highway, were only revealed on Thursday night. "Turn right at the fluoro vest hanging in the tree," people were told.

A bush doof attendee, who did not want to be named, told The West Australian the atmosphere early on Sunday when Mr Fairchild reportedly went missing was happy and peaceful.

Lasers lit up the night sky while hippies in their 70s smoked cigarettes and painted portraits.

The bush doof in full swing.





Drug use was rampant.

"Ecstasy, acid, cocaine, heroin, pot . . . you could get anything there," the partygoer told The West Australian. "I'd say 99 per cent of the people there were on drugs."

As the soiree tapered off on Monday morning - about 60 hours after it all started - weary-eyed campers woke to the law tapping on their car and tent windows. "I don't think anyone knew someone went missing," the man said.

"It's a big area and there are no lights. It's pretty dark."

Other attendees were shocked when police visited their homes to question them.

"The bush doof is fun if you are careful," the man said.

"It's always going to be unsafe going somewhere everyone is taking drugs but usually you just stay with friends.

"It was freezing. If you get lost out there that's going to be a problem. If you're not with Telstra, you have no signal."

A Department of Parks and Wildlife spokeswoman said the department was aware parties were sometimes held illegally on Parks and Wildlife-managed land and would investigate any big organised event.

“Generally the department is only alerted to such events after the fact, when it receives complaints about discarded rubbish and damage to vegetation or infrastructure,” she said.

“Parks and Wildlife may also investigate a range of other offences under the CALM Regulations that may arise from unauthorised events, including littering, clearing or damaging vegetation, lighting fires, illegal camping, creating a nuisance, offensive noise and taking forest produce.”