Biodiversity benefits of pest control


New Zealand's TBfree programme aims to eradicate bovine tuberculosis from the country's cattle and deer herds and remove the disease from wildlife.  

The pest control employed to achieve that also improves the natural balance of native forests. Some of the predators that destroy habitat and eat native birds and eggs are also implicated in the spread of TB. 

Pest control and surveillance targets possums and ferrets and also kills rats and stoats.  

Removing predators with ground and aerial pest control gives birds and grubs, frogs and insects a chance to recover.  

Research in important wilderness areas like the Catlins, the West Coast, Kahurangi and the central North Island shows bird numbers, nesting success and revegetation improves after pest control.  

Birds such as Robin, Rock Wren, Mohua, Rifleman and Whio rebound after aerial 1080 drops, and sustained ground control deliver richer biodiversity. 

OSPRI works with DOC on the Battle for our Birds and supports the volunteers helping to build a predator-free, disease-free future for all Aotearoa's in habitants.

The biodiversity benefits of pest and predator control are indisputable. 

About five-point-five million hectares of New Zealand are targeted each year by TBfree pest control and survey operations, on the ground and from the air - whichever method is most suitable for the terrain. 

Aerial operations = 10%

Ground operations = 90% 

Trapping and ground baiting covers most of the work aerial. 1080 operations knock down predators in large-scale operations over difficult terrain. Both methods enable threatened birds, bats and bugs to thrive again. 

Researchers monitor key bird and bat species to measure the effects of pest control, and track vulnerable species to see how breeding success improves.  

The improvements tell the story. 

Nesting success of native birds following aerial 1080 operations

  • Robin: 7% success before 1080 --> 50% success after 1080 
  • Rock Wren: 20% success before 1080 --> 80% success after 1080 
  • Mohua: 57% success before 1080 --> 89% success after 1080 
  • Rifleman: 29% success before 1080 --> 100% success after 1080 

The TBfree programme aims to prove freedom from disease in livestock (cattle and deer herds) by 2026, from possums by 2040, and eradicate TB from New Zealand by 2055. 

The pest control work to achieve those goals will make New Zealand's wild environment a healthier and more diverse habitat for all native plants and animals. 

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