Benefits of protection outweigh 1080 deaths
“A few” kea are dying from poisonous pest control operations, but there’s a longer-term benefit in the fight to protect the endangered mountain parrot, according to the Department of Conservation.
By Local Democracy Journalist Brendon McMahon
Species studies aimed at monitoring the effects of predator control operations were described by the regional head of the DOC’s West South Island National Predator Control Program, Tom Belton, during a West Coast Conservation Board meeting at Karamea.
Belton said the destruction of kea consuming 1080 poison bait remains “a major challenge” for the department in its pest control work.
“There’s a lot of work going on in this space to reduce the impact on the kea. What we’re doing now, what the science says, that even if a few die, the benefits last for at least two seasons,” did he declare.
He pointed out that:
* Kea are very sensitive to introduced predators.
* Aerial 1080 has a proven kea advantage at the population level, but an individual kea can be poisoned in aerial 1080 operations.
* The DOC has maintained a code of practice for aerial 1080s in kea habitat to mitigate risk.
* The department’s Kea 1080 Risk Mitigation Technical Advisory Group with Te Rūnanga o Ngāi Tahu, Ospri and Zip (Zero Invasive Predators) is researching to further reduce the 1080 risk to the kea.
This included field trials to test whether a bird repellent, anthraquinone, can be used to train the kea to avoid 1080 grain baits.
Other individual successes on the West Coast were whio in Oparara and kaka in South Westland.
The whio (blue duck) study site at Oparara, near Karamea, was one of eight priority management sites for the species and showed that with predator control the whio had dropped from 23 pairs in 2012 to 71 last year.
The continued trapping of predators along the fast-flowing rivers where the whios live, as well as the 1080 aerial falls in the surrounding area were the factor, Belton said.
An ongoing study of kaka in a South Westland study area has shown the effect of predation on the species without predator control.
“Nesting is really affected by predators.”
It showed a sharp contrast between a 55% successful nesting rate, following the use of 1080, versus 2% of nests able to produce chicks where 1080 was not used.
DOC had found that 30 times more kaka chicks were produced within a year of applying 1080.
The mortality rate in adult birds was also relatively affected: it decreased to 3% in a “treated” area compared to 20% in an “untreated” area.
Local Democracy Reporting is public interest journalism funded by NZ On Air.