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Important information for dog owners

Important information for dog owners

Important information for dog owners

Dog owners are advised to be extra vigilant in and around the Rimutaka Ranges following the completion of a large aerial possum poisoning operation yesterday (30 August, 2012).

The operation, jointly conducted by the Animal Health Board (AHB) and Greater Wellington Regional Council (GW) was carried out to protect cattle and deer herds from bovine tuberculosis (TB), and improve the health of native forest. Around 28,000ha of the Ranges has been treated with biodegradable 1080 poison baits, including parts of the Rimutaka Forest Park, the Pakuratahi Forest, the Kaitoke Regional Park and GW’s Wainuiomata-Orongorongo Water Collection Area.

Baits and poisoned possum carcasses are extremely toxic to dogs and warning signs have been placed at all main public access points to the operational area. These will remain in place until possum carcasses have fully decomposed – about six months. Dog owners are strongly advised to keep their dogs safe from accidental poisoning by keeping them out of the operational area until all the warning signs have been taken down.

There is a small risk that flooding could wash possum carcasses out of the operational area and down the Hutt River. To guard against this, GW has set up a flood warning system. If there is heavy rain, staff will be alerted and a patrol sent out to check the sides of the Hutt River for any possum carcasses. If carcasses are found, they will be removed. Warning signs will be posted in risk areas along the river and GW will notify local media.

Any dogs suspected of eating possum carcasses should be taken to a vet immediately. All local vets have been alerted to the operation.


Additional information


  • Bovine tuberculosis (TB) is a highly-infectious disease that can jeopardise New Zealand’s access to premium beef, deer and dairy export markets. In high-risk areas, possums are linked to more than 70 per cent of new TB outbreaks in herds.
  • Maintaining a healthy and intact forest catchment ensures the continuation of a high-quality water source for treatment and supply. The roots of the trees bind the soil and help keep sediment out of the water, making it much easier and less expensive to treat. Possum browse damages our forests and makes them less effective at filtering our water.
  • Possums are also targeted in the water collection area because they carry diseases such as bovine tuberculosis, and transmit organisms such as giardia and cryptosporidium, which are contamination risks to the water supply and may lead to serious illness. International best practice advocates effective catchment management as part of a multi-barrier approach in guarding against contaminated water supplies.
  • Sodium fluoroacetate (1080) is highly soluble in water and biodegradable, so does not persist in water or soil. Over 100 water tests have been carried out within the Wellington Region during previous aerial 1080 operations. None have shown any trace of 1080 contamination.
  • While previous testing has not detected any 1080 in water samples, all water intakes in the Wainuiomata-Orongorongo Water Collection Area were excluded from the aerial operation as a precaution. Further, water extraction from these intakes has been stopped until the Medical Officer of Health (MOH) is satisfied that there is no trace of 1080 in the rivers at the water intakes. In the meantime, water will be supplied from GW’s Te Marua and Waterloo water treatment plants.
  • The MOH requires that no 1080 is detectable in water supplies down to a concentration level of two parts per billion parts of water. At two parts per billion, a 60kg person would need to drink 2,300 litres every day for several weeks for any illness to occur.
  • For more information on how and why 1080 is used in New Zealand, visit You can download the Parliamentary Commissioner for the Environment’s 2011 report from

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