Find out about an operation to control possums and rodents in Papaitonga Scenic Reserve.

Reviewed: 15 January 2015

DOC is continuing possum and rat control in Lake Papaitonga Scenic Reserve. We are changing the toxin (brodifacoum) we have been using since 1996 to two different toxins.

Factsheet and map (PDF, 204K)

Possum control

The pesticide used for possum control has the brand name Feracol (cholecalciferol). It will be placed out through the reserve using 'strikers' which are a biodegradable potato starch bait station with a highly palatable feed paste with the active ingredient cholecalciferol added. These will be stapled to trees approximately 1 m from the ground along current bait station lines. Feracol will not be placed within 20 m of public walking tracks.

Rat control

The pesticide used to control rats in the area is diphacinone (brand name Pestoff Rodent Bait 50D). These are cereal based pellets approximately 10 mm in diameter and dyed blue. 0.5kg – 1 kg of bait will be placed in existing bait stations every 3 months. Cholecalciferol is also toxic to rats and may also have an impact on the rat numbers.


This will be an ongoing operation and warning signs for the new toxins will be placed out immediately before the operation starts. Because of the residual effects of brodifacoum (the old toxin), the old warning signs will remain in place for 36 months from the last application date.

Important information

The pesticides, cholecalciferol and diphacinone, are poisonous to humans and domestic animals.  Poisoning can occur through handling or eating the bait, or consuming dead or poisoned animals.  Treat all baits as poisonous, and keep domestic pets out of the operational area.

Animal carcasses will remain poisonous until they have decomposed. There is no health risk associated with using this area provided the following rules 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 (includes buffer zones below).
AnimalWithin buffer Pesticide
Pigs 2km Any except cyanide or cholecalciferol
Rabbits 200m Any except cyanide or cholecalciferol
Hares,Wallabies or Live Possums  1km Any except cyanide or cholecalciferol
Deer or any other wild animal  2km Any except cyanide or cholecalciferol

The presence of warning signs indicates that pesticide residues may still be present in baits or animals. The removal of signs will tell you that you can resume normal activities in the area. If in doubt, check with DOC.

Why we are controlling possums and rats

Possums and rats affect the health of native ecosystems. They eat seeds and seedlings, impact on forest regeneration, compete with native wildlife for food and prey on birds, eggs and invertebrates.

Possum and rodent control improves habitat and decreases predation on native wildlife. This area contains threatened native species which are vulnerable to predation from possums and rats.

Control of possums and rats will significantly benefit these threatened species. We plan to carry out ongoing control to ensure this significant area remains healthy.

Why we are using this method

We have found poison bait to be an extremely effective form of possum and rat control at this site.

When used appropriately feracol and pestoff rodent bait are effective toxins for keeping possums and rats at low levels.

Because we are switching to new toxins we will be continuing to monitor pest numbers to make sure we are achieving our target goals.  

Operational planning

The use of these pesticides requires DOC's internal approval process to be met. This ensures the operation meets our quality management standards for pesticide use. 

This approval entails a detailed assessment of risks involved with the operation. The document produced is called an Assessment of Environmental Effects, and a copy for this operation can be obtained from the DOC office in Palmerston North.

If you suspect poisoning

  • Contact the National Poisons Centre phonel 0800 764 766 (0800 POISON).
  • Or dial 111 and request an ambulance.
  • In the case of a domestic animal being poisoned contact a local veterinary service.

Map of operational areaMap of pest control operation area in Papaitonga Scenic Reserve.


Te Papaioea / Palmerston North Office
Phone:   +64 6 350 9700
Fax:   +64 4 471 1117
Address:   28 North Street
Palmerston North 4410
Postal Address:   Private Bag 11010
Manawatu Mail Centre
Palmerston North 4442
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