142 bait stations in a grid of seventy-five square metres, now cover the whole island.
Monitoring the number of Fernbirds helps to indicate whether the group has been successful in reducing the number of rats. A recent spike in Fernbird numbers is a positive sign, indicating zero rats.
"The exciting thing is that our Fernbird counts have risen to thirty-six, whereas last year they were only averaging twenty. And the year before that only ten," Mr Slade said.
Land Management Officer at the Bay of Plenty Regional Council Tim Senior said the results are "fantastic."
"Having got rid of the rats on the island also means that a whole lot of other birds will be thriving on the island too, including some quite rare ones," Mr Senior said.
Access to the island is dependent on tides and when the group re-bait they've got to cover the whole island.
"It would be great to have another volunteer, with a boat," Mr Slade said.
Made with funding from NZ On Air.