The blue mushroom made famous by the $50 note and the kōkako bird have been found flourishing in the Rotorua district.
Werewere-kōkako blue mushrooms have been spotted this autumn by the team and visitors at Rotorua Canopy Tours.
In a statement, the tours team said it was an exciting find.
The return of the indicator species signifying their efforts to regenerate the forest was making a difference in the region's biodiversity.
The company has been operating out of the Dansey Rd Scenic Reserve in partnership with the Department of Conservation since 2013.
They have successfully trapped the area, cutting pest populations and allowing native flora and fauna to come back to the virgin forest, including the blue mushroom which is found only in New Zealand and India.
It was also a thrilling find for conservationists who understand that this discovery indicates a healthy forest and low pest numbers.
According to the Rotorua Canopy Tours website it was still unknown whether the blue fungi were poisonous or not, however they were not edible.
Paul Button, tour company general manager, said rats and possums eat the werewere-kōkako as well as velvet worms and striped skinks.
"A month ago, we spotted another striped skink, one of 150 seen in the wild. It's rewarding seeing the fruits of our trapping labour pay off in the return of these fascinating species."
Button's comments came on the heels of a newly released United Nations' biodiversity report that showed biodiversity decreasing across the globe.
"The positive indicator shows that we can reverse the damage if we're willing to work together and invest the effort into preserving our natural environment."
New Zealanders have seen first-hand the rapid decline in biodiversity that occurs from man-induced habitat loss, pollution and introduced species, said Button.
"This UN report shows that on a global scale human exploitation is putting close to one million species at risk of extinction. The ease at which species can drop off is something we've seen in New Zealand, with only 25 per cent of our native forest cover remaining, this has had a big impact in a short time," Button said.
"We're lucky as a wealthy nation that we can respond quickly, and we're now working to regenerate our native wildlife across the country.
"Here in Rotorua, we have seen the return of many rare and endangered species in the forest in which Canopy Tours operates, and that gives us hope for the future.
"While humans can have a devastating impact on the environment, we're optimistic about the opportunity to restore the damage we've done through technology and awareness and believe that growth can be symbiotic with preservation and conservation.
"It's not too late to reverse the damage."
Canopy Tours pest trapping background:
2013: First pest traps, single-action Victor traps, placed over 50ha of the reserve. Trap checking and rebaiting required two days' work each fortnight and staff became tired of the labour involved. Canopy Tours realised this wasn't a sustainable model as staff became unmotivated in maintaining traps regularly.
2014: Canopy Tours trial Goodnature traps with great success and traps kill multiple times before needing to be reset (24 times for rats and stoats, 12 times for possums).
2015: Canopy Tours replace all single-action traps in the 50ha area with Goodnature traps and extend the trapping network by another 50ha, taking the total area to 100ha.
2016: Another 80ha of the reserve added to the trapping network.
2018: 250ha of the reserve now covered by a network of 700 Goodnature traps.