What's happening?
The Department of Conservation (DOC) and the Animal Health Board (AHB) have joined forces to boost native bird populations, protect the health of the forest, and reduce the risk of bovine tuberculosis to cattle and deer herds in the Wairarapa. This will be achieved through an operation to reduce the number of possums, stoats and rats in around 30,000 ha of the Tararua Forest Park.
When is it happening?
A possum and rat prey on chicks in a nest
The operation is planned for the first period of favorable weather from1 August 2010. This period was chosen as it coincides with the start of the bird breeding season, and targeting predators at this time should provide a boost to native bird populations.
How is it happening?
Pre-feeding with non-toxic cereal pellets (coloured brown) will occur 1-2 weeks before the operation. These non-toxic baits will be sown by helicopter throughout the operational area. Pre-feeding allows possums and rats to get a taste for the baits, overcoming any bait shyness and improving the kill rate for these species.
Following the pre-feeding, cereal pellets containing 0.15 percent 1080 by weight will be distributed by helicopter. These pellets are green, 2 cm in diameter and 3-4 cm long, and are toxic to humans. The pellets will be sown at a rate of 2 kilograms per hectare - about 160 baits or 3 g of toxin.
Warning signs will be placed at all main access points to the operational area, as well as in all huts. All people entering the area must observe the cautions and follow the advice provided by these signs.
What is 1080?
1080 baits
1080 (sodium fluoroacetate) is a naturally occurring compound found in a range of plant species, particularly in Australia and South Africa. It is also found naturally in puha, tea leaves and guar gum - a binding agent sometimes used in food production.
1080 is biodegradable so does not accumulate in the environment or persist in soil or water. In favourable conditions soil microorganisms break down 1080 in about two weeks.
1080 has no lasting effects on animals that consume a non-lethal quantity. It is eliminated from these animals in two to three days.
Why are we using this method?
1080 is an effective toxin for targeting pest mammals, such as those which prey on native animals and plants and spread diseases like bovine tuberculosis. 1080 is particularly suited for use in New Zealand because, unlike other countries, NZ has no native ground dwelling mammals that can be affected by its use.
The area to be treated in this operation covers a huge area of remote and rugged terrain, making ground control impractical. 1080 is the only toxin approved for aerial distribution on the New Zealand mainland. It is estimated that controlling possums alone using ground control would cost 2-3 times as much, and many difficult areas would be left untreated. In addition, ground control would not effectively control rats.
When combined with satellite navigation technology, which ensures even coverage of pellets and allows the pilot to avoid specific areas such as water ways and huts, aerial 1080 application is the most efficient and effective control we could use for this operation.
Why is the AHB controlling possums?
The AHB is controlling possums along the eastern foothills of the park from the Tauherenikau River north to the Waingawa River, to reduce the risk of cattle and deer herds being infected with bovine TB which is carried and spread by possums.
Previous aerial operations have been successful in controlling the disease but since the last AHB operation in 2003 possum numbers have risen considerably in this area. Possums need to be controlled again to prevent an increase in the disease.
Bovine TB is an infectious disease that can affect domestic cattle and deer. It is important in New Zealand because of its potential to affect overseas meat trade. High value world markets can choose not to accept dairy, beef and venison exports from countries with high levels of infection.
Why is DOC controlling pests?
North Island kaka
Possum control undertaken in the park since 1994 has successfully protected high-altitude fuchsia forest, but the timing and intensity has been insufficient to benefit forest bird populations.
DOC's Project Kaka -Tararua Nature Recovery initiative aims to restore the forest and its wildlife within a 20,000 ha belt across the park, from Otaki Forks to Holdsworth. Rats and stoats will be targeted as well as possums, to protect native birds during the vulnerable nesting period.
Possums eat native plants, severely damaging the forest canopy and dramatically reducing populations of threatened plants such as mistletoe. Possums, rats and stoats kill forest birds, reptiles and invertebrates, preying on eggs, young, and adults.
What are the effects of 1080?
Humans:
Eating as few as one or two baits could seriously endanger a child's life. Keep children under close supervision and do not interfere with baits.
The symptoms of poisoning normally appear between 30 minutes and four hours after exposure. They include vomiting, involuntary hyper-extension of the limbs, convulsions and finally cardiac and respiratory collapse.
Dogs:
Dogs are ten times more susceptible to 1080 poisoning than other species - even a tiny amount will kill them. It is critical that they do not access bait and are not allowed to scavenge carcasses, which remain toxic to dogs until they are fully decomposed. The bones, skin and fur are not toxic. Dog owners must NOT take dogs into the control area until the warning signs have been removed.
Deer and pigs:
It is an offence to sell meat products which have been exposed to 1080. Do not hunt or take game from within a 2 km radius of the poison area either for sale or for personal consumption (human or pet). Hunting can recommence four months after control or after 2 months if 100 mm of rain has fallen. Check the Department of Conservation's pesticides summary for further information.
Water quality:
1080 operations do not contaminate water supplies; however, DOC and the AHB are aware of public concerns relating to potential contamination of drinking water supplies following aerial 1080 operations. Controls over aerial applications require aircraft to avoid major water bodies or water ways that flow into potable water supplies.
The Medical Officer of Health requires that if any contamination of water supplies occurs it must not exceed 2 parts per billion. At 2 parts per billion, a 60 kg person would need to drink 2,300 litres every day for several weeks for any effects to occur.
More than 100 water tests have been carried out in these operational areas during previous operations. None have shown any trace of 1080 contamination.
What precautions should be taken?
There is no health risk in using this area if the following precautions are observed:
- DO NOT handle any bait.
- DO NOT allow CHILDREN to wander unsupervised.
- DO NOT bring DOGS into this area.
- DO NOT handle or eat ANIMALS from this area.
- HUNTERS must heed all restrictions included in the Hunter Permit Pesticides Summaries, including not taking animals for consumption.
What do I do if I suspect poisoning?
Contact:
- Emergency services (111) or,
- National Poisons Centre Tel. 0800 764 766 (0800 POISON).
- In the case of a domestic animal being poisoned, contact a local veterinary service.