Image: Sabine Bernert ©


Kea nesting improves after 1080 treatment.


New Zealand’s mountain parrot is renowned for being smart and inquisitive. Kea will explore novel objects and scavenge for human food given the opportunity. But this can be their downfall when birds interfere with traps and poison bait meant to protect them.     

Monitoring kea after 1080 operations is a priority for DOC scientists. It allows us to weigh up benefits of pest control with the risk that 1080 will kill some birds.

Overall, monitoring shows that when predators are controlled with well-timed aerial 1080 treatment and/or traps, about 70% of kea nests are successful, ie produce at least one chick.

Without pest control, typically about 60% of kea nests fail – mostly due to being preyed on by stoats or possums. 

But, nest failure climbs to more than 90% in a stoat plague, the year after beech or rimu forest seeding. Only about 10% of nests are successful in these years.

Without pest control kea will continue to decline.

Studying the benefits of pest control for kea

DOC has monitored kea nesting success in Kahurangi National Park since 2009. 

In the 2015 and 2016 kea breeding seasons, on average 50% of monitored nests produced young kea.  This followed aerial 1080 predator control in 2014 and 2016.

This is a big improvement on previous years without predator control in Kahurangi.  Between 2009 and 2014 only 2% of nests were successful in areas without predator control. 

DOC tracked a sample of over 20 kea through 1080 predator control operations in Kahurangi National Park in 2016 and none were lost to 1080 poisoning. 

Our scientists calculate that kea populations are better off after 1080 treatment than without it.  If predators are not controlled after a beech mast or seeding event, high stoat levels wipe out most nests and kill adult birds too. 

Kea nesting success bar graph.

View larger graph (SVG, 35K)

Other monitoring results

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