Parrots Reclaim Island Paradise After Predator Eradication

Raoul Island, part of New Zealand's Kermadec Islands, has witnessed a significant ecological recovery. The Kermadec parakeet, a species not recorded breeding on the island for approximately 170 years, has returned. This successful recolonization occurred after a comprehensive multi-species eradication project between 2002 and 2004 removed invasive predators like cats and rats.

Historically, Raoul Island was abundant with native birds in 1836, but the establishment of feral cats by 1872 and Norway rats by 1921 led to a steep decline. A 1991 study noted that parakeets were only represented by stragglers from the nearby Herald Islets. The removal of goats in 1984 and subsequent eradication of cats and rats paved the way for the parakeets' return.

A 2008 survey revealed a thriving parakeet population, with scientists capturing 100 individuals, 44% of which had hatched that year. This event is considered a pioneering success in parrot conservation, demonstrating that bird populations can re-establish breeding sites once predators are eliminated. Researchers emphasize prioritizing eradication in areas near remnant populations.

Future research will focus on food availability, as a 2013 study indicated that starvation, not predation, could become a limiting factor for nestling survival in predator-free environments. The current population size on Raoul Island remains to be measured, as the 2008 survey was a single snapshot.