The Department of Conservation (DOC) completed its Battle for our Birds aerial 1080 pest control operation in the Waitutu Forest in Fiordland National Park yesterday.
The Waitutu operation will protect South Island kākā, mohua/yellowhead and mistletoe over 30,000 hectares of lowland forest by targeting possums, rats and stoats, and will also benefit other forest birds such as ruru/morepork and tūī.
DOC Fiordland Conservation Services Manager Lindsay Wilson said monitoring results show that rodent numbers were rising rapidly and possums had also increased since the last pest control in 2010.
“Timing our pest control now will achieve a triple-hit of rats, possums and stoats and protect our vulnerable native birds as they nest and raise their young this spring and summer.”
In 2010 an aerial 1080 operation over 25,000 hectares reduced possums, rats and stoats to low numbers and as a result, bird populations such as kākā and robin increased, said Wilson.
This year’s operation extends the treatment area to protect a nationally significant mistletoe population and provides an additional pest control buffer to the west.
The application of biodegradable 1080-laced cereal baits over the target area - which extends from the south coast north to the Princess Mountains and between Big River and Wairaurahiri River - follows treatment of the area with non-toxic “pre-feed” bait just under a week ago.
The operation followed stringent safety procedures and buffer zones were in place around significant waterways such as rivers and lakes.
Warning signs advising the public about the dangers of the pesticide are in place at all entrance points and the boundary of the Waitutu treatment area. Public access to the Thicket Burn Campsite is closed until further notice.
The Department would like to acknowledge and thank adjoining landowners and visitors to the area for their patience while the operation was underway and road closures were in place.
For more information on DOC’s Battle for our Birds pest control response see: www.doc.govt.nz/battleforourbirds
Waitutu is a nationally significant lowland mixed podocarp and beech forest and site for mistletoe plants. It is a stronghold for South Island kākā and has mohua/yellowhead, as well as a range of other forest birds such as robin, ruru/morepork, kererū and riflemen.
The Waitutu treatment area includes private Māori land. DOC works with the Waitutu SILNA land owners to protect the forest ecosystem from introduced pests under a covenant agreement between the owners and the Crown.
The Battle for our Birds pest control operation used the biodegradable poison 1080 laced in cereal baits, which were sown at a rate of 2 kilograms per hectare using GPS-guided feeder systems. The poison content of the bait is about 3 grams per hectare.
Aerial 1080 is an effective method of knocking down plague levels of rats and stoats (by secondary poisoning) following a beech mast (seeding), and also possums, before they overwhelm native birds and bats, which are particularly vulnerable during the breeding season and when roosting in holes in trees.
The pest control operation had two separate phases - the sowing of non toxic “pre-feed” bait, followed by biodegradable poison 1080-laced cereal baits at least five days later.
Monitoring the effects of the pest control operation will be undertaken in coming weeks including the knock-down of rats and long-term monitoring of forest bird species.
The Waitutu operation is one of 22 confirmed Battle for our Birds operations that will use aerially applied 1080 over about 600,000 hectares of conservation land to knock down rising rat and stoat numbers fuelled by unusually heavy seeding in South Island beech forests.
The coordinated Battle for our Birds pest control programme is targeted to protect the most at-risk populations of mohua/yellowhead, kākāriki/parakeet, kiwi, whio/blue duck, kea, kākā, rock wren, giant land snails and native bats at sites across the South Island.