"At this stage, it appears that the mountain biker involved has had a fall after landing badly following a jump towards the end of a ride. We believe he is an experienced rider," he said.
"Gravity Park has highly-skilled first-aiders who are trained to a pre-hospital care level. They were on the scene within five minutes, stabilising the rider and assisting St Johns and the rescue helicopter with evacuation."
He said Worksafe had been notified, as was standard procedure.
"Under Skyline's extensive health and safety protocols, we will be conducting our own investigation. Until this investigation is complete, we are unable to provide any further details."
The man and his partner were four days into their New Zealand sightseeing and mountain biking holiday, a rescue helicopter spokesman said.