The latest survey was completed eight months after a large scale pest control operation led by Rotoehu Ecological Trust which has actively managed pest control in the area since 2013.
The types of pest control included a mixture of pest controls including ground-based trapping and pesticides, but 1080 was not used.
Rotoehu Ecological Trust chairwoman Sarah Orton said the survey team reported most of the kōkako pairs had fledglings with them which indicated healthy and robust population growth.
Titipounamu (rifleman), pōpokatea (whitehead) and toutouwai (robins) were also spotted in abundance during the survey.
DoC supervisor Carrie Abbott said the results were fantastic and a testament to the time and effort the ecological trust dedicated to pest control.
Safe head of campaigns Marianne Macdonald said while animal population control was complex, Safe urged the Government to prioritise research into more humane alternatives.
"No animal deserves a slow and painful death. So let's look for other options," she said.