
Why does removing rats and stoats from a scatter of small offshore islands bring back flightless parrots and ground-nesting seabirds that had not bred on the mainland for over a century?
New Zealand's kākāpō population has climbed from 50 birds in the 1990s to over 200 today, entirely because rats, stoats and cats have been eradicated from three small offshore islands — Whenua Hou, Anchor and Chalky. Here's how removing one pressure lets an 80-million-year-old ecosystem reassemble itself.















