The 4-year-old Border collie/springer spaniel cross, owned and trained by Department of Conservation (Doc) ranger and handler Paul van Klink, is lending a paw in efforts to save the endangered native whio.
The blue duck is usually found in remote rivers nestled among mountainous valleys and still lives in the headwaters of Lake Wakatipu, including the Routeburn and nearby valleys.
However, numbers of blue duck are so low Doc Queenstown conservation partnerships manager Greg Lind said he was concerned that without some help , it might disappear from the Wakatipu entirely.
''This native duck is highly vulnerable to deadly stoat attacks and their numbers are falling,'' Mr Lind said.
''With so few blue ducks remaining, unless the decline is halted, the species faces a real risk of becoming locally extinct.''
Mr Lind said to save the blue duck rangers must first know where they lived and where they could safely raise ducklings, which could be a challenge as the species was elusive.
But with Hoki's keen sense of smell, rangers completed enough monitoring to plan conservation efforts.
''Hoki is a bundle of energy and works tirelessly all day bounding across boulders and through streams to find the ducks,'' Mr van Klink said.
''She is a super sleuth and can find ducks under boulders, in pools away from rivers and in old log hideaways.
''Our best days together are when we finally track down some of the shy ducks doing their best to hide from Hoki's inquisitive nose.''
Hoki was certified through the Conservation Dogs programme before being allowed to enter national parks, and she is muzzled at all times.
Mr van Klink said it was a long road for Hoki to gain approval and it took time for him to understand Hoki and how best to control her to work safely with native birds.
''The benefits to whio conservation are enormous; without Hoki's sharp-nosed and friendly manner much of Doc's whio monitoring would be prohibitively time-consuming.''
The work is part of the Genesis Energy Whio Recovery Programme, a partnership between Doc and Genesis Energy which aims to help ensure the future of the threatened bird.
The possible return of blue ducks to the Routeburn and nearby valleys is supported by Air New Zealand. The airline helps fund intensive predator trapping in those areas to cut stoat numbers and make it safer for blue ducks to raise their ducklings.