Her student-led group plants trees and traps invasive animals that are killing native birds. Rats (left) eat bird eggs and chicks, while possums (right) eat tree foliage, reducing habitat and food supply for native birds. The songs of other native birds can be heard echoing in the trees, a hopeful sign for the group. Brushtail possums devour tree foliage, reducing the food supply and habitat for native birds, so restoring the forest is a key step in bringing birds back. He’s one of about 600 trappers across town who volunteer to combat invasive species to help protect New Zealand’s native birds.