The New Zealand Herald reported Walker had now been found and is "fine", according to a family friend.
A post on the Te Araroa hiking trail social media page today stated the family were seeking information on his whereabouts after he had failed to contact them.
Mr Walker was tramping on his own and was expected to head into the Longwood section of the Te Araroa Trail on Saturday or Sunday.
The last communication he had with his family was on the beach section before Riverton, in Southland.
However, his mother had since checked with the Riverton and Colac Bay Campgrounds and he had not shown up to either.
While he may have camped on the beach and carried on through, his mother doubted it.
‘‘Blake has already done SOBO Cape to Arthur’s Pass pre-lockdown and always checked in when in pockets of service,’’ the post stated.
‘‘[It was] So unlike him to have not at least once checked his phone over past four days.’’
Police said they were notified this morning a tramper had not been in touch as expected.
A police spokeswoman confirmed the tramper was fine and emerged from the trail of his own accord.