The Department of Conservation (DOC) is planning aerial pest control over a large area of Kahurangi National Park this spring to protect native species from predator plagues that could decimate their populations.
The pest control is needed to protect whio, rock wren, kea, kaka, great spotted kiwi, Powelliphanta snails, long-tailed bats and other vulnerable native species.
The Kahurangi pest control is part of a major national DOC ‘Battle for our Birds’ predator control programme aimed at protecting at-risk native species’ populations from rat and stoat surges.
An exceptionally heavy beech seeding and seedfall, known as a mast, in many forests this year is providing plentiful food to fuel rapid rises in rodent numbers. This in turn leads to rising stoat numbers due to the abundance of rodents to feed on.
DOC is planning for pest control, to be ready to act quickly to protect native species this spring. Final decisions nationally on where pest control will take place will be based on rodent tracking and beech seed monitoring in coming weeks.
DOC Motueka Conservation Services Manager Mark Townsend says monitoring in various parts of Kahurangi National Park showed rat numbers at levels at which they could reach plague proportions by late spring if not stopped.
“Vulnerable native birds struggle to survive when nesting under normal predator pressures but with the high predator numbers expected this year it could be a disastrous breeding season.
“Aerial pest control this spring will help protect native birds from predator attacks during their critical breeding season. This will enable greater nesting success with more chicks and nesting females surviving to build populations.”
The planned Kahurangi pest control programme covers approximately 276,000 hectares in northern and eastern parts of the park. Pest control over a large area of the park will help slow predator reinvasion and provide greater protection for the park’s native wildlife.
The pest control will entail aerial application of cereal baits containing biodegradable 1080 pesticide. This is the most effective method over large areas and difficult terrain. It rapidly and substantially reduces rat and possum numbers, and also stoat numbers through their eating poisoned carcasses.
Although trapping networks are in place in some parts of Kahurangi, research has shown beech mast predator surges can overwhelm trap networks. Ground control on its own cannot protect threatened native bird, bat and snail populations from beech mast predator plagues.
Great spotted kiwi