Because poisons and trapping, traditional methods of pest control, have limited success and seldom last long, the creators of the plan decided to enclose the 34 square kilometres of bush with a 47 km pest-exclusion fence to create an ecological island. When the environment is rendered suitable, the area will be repopulated with the entire suite of charismatic species that may now be locally extinct, such as North Island brown kiwi, North Island kōkako, kakariki, tuatara and many others. Kaka already visit regularly and are likely to become resident if suitable methods are employed.