Voluntary pest-trapping on hills above Arrowtown is being undermined by someone vandalising traps.
Predator Free Arrowtown instigator Ben Teele, whose group aims to bring back native birds by trapping rats, possums and other critters, estimates 30 to 40 have been removed, including a whole line of traps recently laid along New Chums Gully.
That's about 10 per cent of all traps laid to date.
"The community is quite aggravated, to say the least," Teele says. "Each time we lose one of those it's all that effort and money and resources gone, so people get frustrated."
He says each trap costs about $120 in materials - "then there's the construction cost and then the effort of volunteers to drag them up hills".
He adds that the recent vandalism's poorly timed as there's about to be a pest explosion caused by an abundance of seeds.
Teele says with traps being removed so often, even off the beaten track, he suspects a local person is the perpetrator.
If there's any consolation it's that several traps have been found, mostly near where they were taken.
"There's one person who is doing damage but there is a whole bunch of people behind who are on the lookout."
Meanwhile, Teele says Arrowtown Village Association donation boxes are being broken into at Bush Creek, with about $60 to $70 a time - donated for track maintenance - being stolen.