1080 drop planned to fight ‘mast feasters’

An aerial 1080 drop over 30,000 hectares in the Ruahine Range will take place this spring to battle an expected surge in predator numbers.

Every two to six years beech trees flower and produce massive quantities of seed, in an event known as a ‘‘mast’’, which draws increased numbers of predators. Sampling by the Department of Conservation in February confirmed a mast was occurring in the northern area of the Ruahine Range this year.

The operation will begin after September 6, as weather permits. Cereal baits containing biodegradable sodium fluoroacetate, known as 1080, will be dropped over 30,000ha. The targets will be rats, stoats and possums, which will be present in much greater numbers because of the short-term bounty of food from the mast.

DOC acting operations manager for Manawatu Duncan Toogood said the operation had been planned to give maximum protection to the highly valued species in the area.

‘‘This operation will offer a fighting chance to Ruahine populations of at-risk species, such as whio, kiwi, giant land snails, robins (toutouwai), kakariki, bats (pekapeka), red mistletoe, dactylanthus, and Turner’s kohuhu.’’

‘‘This increase in animal pest numbers could lead to the loss of our threatened taonga species. Once the seed runs out, these predators will look for other food sources – our native species,’’ he said.

The operation will take place over two days. Afterwards, there will be a withholding period of up to 10 months, meaning hunters are advised not to take meat from the area.

The operation is part of an ongoing battle by DOC to reduce rat, stoat and possum numbers.

Without predator control, only 5 per cent of kiwi chicks hatched in the wild will make it to their fourth birthday, and for every three breeding pairs of whio, only two ducklings will make it to fledging.

‘‘Aerial 1080 is the most effective large-scale pest control tool we currently have and monitoring shows it’s successful in protecting vulnerable species and allowing birds to produce more chicks to sustain and build their populations,’’ Toogood said.

He said community-led groundbased predator control with more than 1000 traps in the ranges was helping, but trapping could never keep up with the ‘‘boom in predator numbers that follows a beech mast, especially over such largescale, difficult terrain’’.

The northern Ruahine operation is one of 34 Battle for our Birds predator control operations taking place across the country this year.