Over the next six months, signs will remind visitors that 1080 has been used in the area. Photo: Supplied
Visitors are urged to be aware of toxins, as New Zealand's biggest regional park re-opens just in time for summer, after a pest-control operation.
The final laying of 1080 bait in the Hūnua Ranges, Waharau and Whakatiwai was completed last month, before the re-opening on Thursday.
1080 bait contains sodium fluoroacetate ‒ a targeted toxin effective against mammalian pests, while minimising impact on native birds and insects.
The operation aimed to eliminate rats, stoats and possums to protect native birds, such as the endangered kōkako, and fauna in the ranges.
Auckland Council regional parks manager Scott De Silva said signs would remain in place for the next six months to remind people that 1080 was used in the area.
"This caution period is one of the operational requirements of using a toxin like 1080, and is a good reminder to visitors they may encounter either bait that hasn't yet broken down or pest animal carcasses.
"Dog owners should not bring dogs to the park for the next six months, as they are highly susceptible to the toxin."
He said those walking near the operational area should make sure dogs are not allowed to scavenge carcasses. Children should also be carefully supervised.
The pest-control operation began in August and was completed in late October.
In addition to removing the dams from service, other safety measures around the water supply included exclusion zones and no flying over the dams.
De Silva said treating a 23,000-hectare area that was popular for public access, and included a water catchment and private land, required many months of careful planning.
"Getting the right weather conditions was a challenge for this operation."
After each block was treated with toxic bait, an extensive track clearance programme was carried out.
This required staff and volunteers walking more than 700km of tracks, and carefully moving baits and carcasses.
A post-control monitoring programme will be carried out to establish how effectively the operation has reduced possums and rats.
Councillor Richard Hills said he looked forward to positive monitoring results being reported in the coming months.
"Reducing predators to protect native species living within the ranges is a key focus for the council," he said.
"We've already seen the success of the pest-control measures we've undertaken in our kōkako population. In 1994, we had just one breeding pair - our most recent census shows we now have 250 breeding pairs."
Hills said the operation was completed just in time for the current breeding season, with the first pairs of kōkako starting to build nests.
Watercare's dams have also been returned to service, following completion of a water-testing programme and approval given by the Medical Officer of Health.
LDR is local body journalism co-funded by RNZ and NZ On Air.
