NZ search and rescue and local police have scrambled teams to look for the missing hiker, according to a report in the New Zealand Herald.
He was last seen at the Waitewaewae Hut at 1:30 pm on Wednesday morning.
Mr Schopf was thought to be wearing black pants, a blue windbreaker jacket, brown hiking boots, and a yellow and black beanie. Mr Schopf was also carrying a large black and grey hiking pack. He is described as having short blond hair.
He was separated from his fellow hikers between Waitewaewae Hut and Parawai Lodge, Otaki Forks. Police have asked to hear from anyone who may have seen Mr Schopf as there were some concerns for his safety.