The caller did not know where the person was going hunting, or who the friend was.
However, police have just confirmed to the Herald "the hunter has got back into cell reception and has made contact - all is fine."
Marcus' mother Jocelyn McKay earlier told Stuff her son's phone was going straight to voice mail.
McKay said her son had been driving a grey Mitsubishi Triton which was also missing.
She believed he was in the Geraldine area but said he could be anywhere in the South Canterbury region.
"I'm trying to be positive, but our whole family is in tears most of the time," she said.
"I can't help but think the worst because it's so out-of-character. He's the sort of person where he's in contact with family all the time, he's very family-orientated. He's one of those boys who's always on his phone."
McKay told Stuff her son had only been hunting a handful of times and did not own a gun.
"I think he was just going out with people who have done it before.
"We've had lots of support from friends and family, and lots of people wanting to go up and have a look. I can't thank those people enough."