The remains were recovered on Saturday by a disaster victim identification unit member in the Rolleston River area. They have been taken to Christchurch for official identification.
Ms Sheppeard's next of kin in Australia have been informed.
The 53-year-old was officially reported missing in January, however she was last heard from on November 19, when she posted a photo of herself on Twitter saying she was "off to the mountains".
A member of the public pointed police to an entry in the intentions book at the Waimakariri Falls Hut, dated November 11, 2020. It had Ms Sheppeard's name on it and suggested she was likely heading to the Waimakariri Col, Rolleston River or Hunts Creek.
Snr Sgt Kirkwood said a helicopter with observers on board searched the area and a drone team from Fire and Emergency New Zealand's urban search and rescue flew the area recording images, which were analysed.
Nothing of note was seen, however several areas of interest were identified which assisted in the planning of the ground operation, Snr Sgt Kirkwood said.
The search area contained high alpine and bush areas, gorges with waterfalls and boulder fields, which proved to be a challenge for search teams.
Three field teams which included LandSar volunteers and police, two Canyon Sar teams, Alpine Cliff Rescue, two police dogs and a LandSar dog with their handlers were flown into the area.
Snr Sgt Kirkwood said the discovery of human remains was not the outcome searchers were hoping for but, pending confirmation, would bring some closure to Ms Sheppeard's family and friends.
- By Georgia O'Connor-Harding, Greymouth Star
