Find out about the impact family pets have on New Zealand's wildlife and learn ways you can reduce the chance of your pet being part of this significant problem.

Keeping pets is a human tradition dating back thousands of years. However cats and dogs have a natural instinct to hunt and can cause damage to New Zealand's native species. You can help control your pets to protect wildlife.


New Zealand's unique species

New Zealand's isolation from the rest of the world has allowed special adaptations of its plants and wildlife. Extensive forests, clear rivers and lakes, food-rich wetlands and unpolluted seas once provided habitats for about 250 bird species, many of them unique to New Zealand. Without predators many became flightless or ground-dwelling - no match for the mammals which were soon introduced.


The first such predators were the kiore (Polynesian rat) and kuri (dog). Kiore rapidly became widespread and as agile climbers, readily plundered eggs and small birds. European explorers brought stowaway Norway and ship rats which caused a significant reduction in ground-nesting land and sea birds, along with land snails and large insects. The remaining array of animal predators arrived with human colonisation, either for company or as game. Rabbits fell into the latter category while mustelids in turn were brought to New Zealand as a poorly planned "biological control" for rabbits.

Effect on biodiversity

The combined effect dealt a stunning blow not only to individual species but to New Zealand's overall diversity. Some species became limited to islands, others became extinct. This is particularly tragic when such species contributed to the distinctive character of New Zealand - and cannot be replaced. Destruction of our bird life is now so comprehensive that world-renowned ornithologist Professor Jared Diamond once declared New Zealand no longer has a bird fauna - just the wreckage of one.

While other human activity contributed to the demise of these species, there is no doubt that hundreds of animals we now regard as pets played - and continue to play - a significant role.

The threat

Devastation caused by cats and dogs

North Island saddleback, pied tit, tui and red-crowned parakeet were eliminated on Cuvier Island, off the Coromandel coast, mostly through predation by cats. Cats were introduced to Mangere Island, in the Chathams, to control rabbits but in addition had also eliminated at least two species of seabirds and most forest birds by 1950. 

Kiwi deaths have been caused by pet dogs on daytime walks and by dogs not tied up at night, at home or camping. Cats and mustelids (ferrets, stoats and weasels) are also predators of kiwi.

The Whangarei Kiwi Sanctuary Study from 2000-2005 showed dogs were responsible for 42 % of kiwi deaths including 69 % of adult kiwi deaths. The effective control of dogs is identified as the most critical part in ensuring the survival of kiwi.

Cats are attracted to the same kinds of wildlife while dogs mainly affect kiwi, weka, rail and penguins.

In addition to these problems, dogs on the loose are well-known for upsetting beach and bush walkers to the extent of serious bites and harassment and for fouling public places.

Destruction from other 'tame animals'

Many apparently 'tame' animals can cause surprising damage in the wild. Even hedgehogs, which eat mainly insects, also adversely affect ground-dwelling birds by eating their eggs. Mustelids are particularly vicious killers affecting birds as large as New Zealand pigeon/kereru, along with lizards, insects, moths and butterflies.

Natural instincts to hunt

Although these stories may sound extreme, destruction on a more limited scale is quite possibly occurring very close to you on a regular basis. For example, advocating kiwi protection from dogs in the Coromandel area forms a major part of the BNZ Kiwi Recovery Programme.

However much you love, care for and train your pet most retain natural instincts to hunt. You may never know the damage they cause. 

DOC's work

The Five Jems Subdivision

The Western Bay of Plenty District Council made a landmark decision in November 1996 to ban cats and dogs from the Five Jems subdivision at Waihi Beach. DOC and Forest & Bird sought the ban to protect sensitive bird populations in a neighbouring salt marsh reserve.

Hunting dogs

Hunting dogs are allowed in areas damaged by pests such as goats and pigs, because they help control the problem.

Threatened species dogs

DOCn uses trained dogs to help find rare bird species. Use is rigidly controlled and dogs are muzzled.

Other restrictions

It's illegal under the Wildlife Act to own more than two ferrets, or keep possums or wallabies without a permit from DOC.

You can help

You as a pet owner can assist in balancing the forces of nature and improving the chance of survival for native species. Here's how:


  • Have your cat neutered or spayed so they can't produce unwanted kittens.
  • Keep your cat well fed and have moving toys for it to play with, so it is less inclined to chase birds, etc.
  • Keep your cat indoors overnight so nocturnal insects and lizards have free reign of your garden.
  • Don't dump unwanted kittens and cats - either give them to the SPCA or ask a vet to put them down humanely.


  • Provide your dog with a roomy pen/kennel where it can be happy and is not free to roam outside your property.
  • Exercise dogs only in areas designated for the purpose -
    • not on beaches
    • not in estuaries
    • not in reserves.
  • Keep your dog on a lead.
  • Be particularly aware of ground-nesting birds - such as kiwi, dotterel and oystercatchers - and keep dogs away from nesting areas.
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