Background
Operation Ark is a conservation initiative in South Island forests.
In the summers of 2001 and 2002 predator plagues in some South Island beech forests led to the near extinction of a species of parakeet (kākāriki), and big declines in mōhua (yellowhead), whio (blue duck) and both long- and short-tailed bat (pekapeka). It was discovered that periodic heavy flowering and fruiting events in beech forests lead to a spectacular rise in rat and stoat populations. When rat and stoat numbers peak, they turn to other sources of food, for example, hole-nesting native birds in the middle of their breeding season.
Offshore islands have been one of New Zealand's conservation success stories but difficult to emulate on the mainland. Short of fencing off entire areas at great cost, pest eradication is all but impossible. A new approach was needed - multi-species intensive pest control at chosen sites. In this way a series of "mainland island" projects were developed.
Operation Ark is a modification of the mainland island concept, with the big difference being cost. By doing the work when it's most needed, the cost of possum, rat and stoat control has been decreased to as little as $17 a hectare a year.
The Operation Ark commenced in 2004 with a budget of $1.24 million a year which has been raised by reprioritising funding from other work. The ten sites were established sequentially over the three years to make the best use of funding. In 2006-2007 an additional $400,000 of DOC funding enabled aerial 1080 operations to control rats at three sites where plagues had been foreshadowed.