In a nutshell...

  • The Australian Brushtail Possum (Trichosorus vulpecula) was introduced into New Zealand in the late 1800s to establish an export fur trade.
  • Only 200-300 animals were released in about 20 locations and now the population is quoted as 70 million.
  • The exercise was an ecological disaster and there is no way New Zealand will ever eliminate the possum. Control is the only hope.
  • Possums kill native wildlife (young birds and eggs) and are vectors (carriers) of bovine tuberculosis which is an enormous threat to our meat and dairy exports.
  • At present, only a small proportion of possums carry Tb, but they can also spread it to other wild vectors such as stoats, weasels, pigs, and deer.
  • The fear is that infected possums will spread Tb to non-infected areas and this will incorporate other wildlife to make control difficult and expensive.
  • Control at present means the use of traps, shooting, and poison (cyanide and 1080).
  • The use of 1080 is most popular but is a highly contentious issue among conservationists, farmers, Forest and Bird members, and politicians.
  • The Greatest hope for a solution lies with genetic engineering as a means of controlling their fertility.

How can you tell if you have a problem?

  • Severe defoliation of trees in the bush, especially Northern Rata.
  • Dead trees (especially Northern Rata) in the bush canopy - are clearly visible from the air.
  • Fruit trees in gardens are being robbed at night.
  • Possum dung pellets around trees bearing fruit or flowers.
  • Rubbish bins are being searched for fruit.
  • The spring buds on roses are eaten with the fur left on the thorns.
  • Many possums were seen on pastures and in the trees at night.
  • Tb infected possums being found (showing cheesy lymph nodes under arms and back legs).
  • Possums hissing and squawking at night and running over the roof.
  • Clear tracks from the bush into the paddocks.  The fur on the fence wire.
  • Sick (dopey) possums are seen out in the paddocks during the daytime.

How can you tell if you're doing well?

  • Regeneration of native bush, and no dead trees in the canopy.
  • Possums not doing damage in gardens.
  • No sign or sound of possums near dwellings.
  • Control and reduction of Tb endemic areas.
  • No new outbreaks of Tb in Tb-clear areas.
  • Stock owners carry out all requirements of the Animal Health Board for Tb control and prevention.

What can you do to improve things?

  • Make sure all cattle and deer on the farm are Tb tested when requested by OSPRI.
  • Before moving stock off the property make sure all documentation and tagging have been done. 
  • Before moving stock away to another farm for grazing, check the Tb status of the farm they are going to. Check with OSPRI for this information.
  • When stock comes back from grazing, check with OSPRI about when tests are needed. They may have to be tested before they come home.
  • Do not purchase stock or have them delivered to your property without the correct documentation. 
  • Make sure NAIT knows about all cattle and deer on your property.
  • Control possums on your property and co-operate with neighbours who are doing likewise.
  • Take great care when using poisons so that they are used correctly with minimal risk to other animals (domestic or wild).  Document any poisons purchased and where used.
  • You need a license to use a firearm.  Make sure your legal obligations have been covered.
  • There is a wide range of possum traps.  Use one which is humane and cannot catch other animals.