Six months after the final application of 1080 in the Hunua Ranges regional parklands, the caution over the treatment area has been lifted.
The caution period, one of the operational requirements of using a toxin like 1080, is a reminder to visitors that they may encounter bait that hasn’t yet broken down or pest animal carcasses.
Hunua Project operational lead and Auckland Council’s Biodiversity Manager Rachel Kelleher says, in addition to the required time passing since bait application, monitoring of bait and carcass breakdown carried out under a number of environmental conditions has also assisted in informing the caution period.
“Carcass and bait breakdown monitoring is carried out to assess how 1080 baits, and animals that have consumed bait, break down,” she says.
Pest animal carcasses and 1080 pellets collected after bait application were placed in secure cages in locations that ranged from deep forest cover to more exposed areas. Both visual assessments and laboratory testing was carried out on both carcasses and bait to determine the likelihood of the toxin still being present.
“The weather plays an important part in this process and the ranges has received a good amount of rain and warm temperatures over the last six months," says Ms Kelleher.
Keeping your dog safe – anywhere, anytime
“A very important message throughout this programme has been the welfare of dogs in and around the ranges.
“Having the caution period in place has been important in making sure dogs are safe. However it is still important for dog owners to keep a close eye on their pets and prevent them from scavenging.
"Regardless of where they are, there is always a risk of poisoning or illness when dogs scavenge on a dead animal,” says Ms Kelleher.
Warning signs have been taken down and messages about the caution period are being removed from the council’s website. Information boards about the pest control operation will remain up at major car parks and arrival areas in the ranges. Information about the programme is also on Auckland Council’s website.
Following last year’s operation pest animals in the ranges are at an all-time low with rat and possum densities significantly reduced across the operational area. When planning for this operation began, rats were tracking at 91.6 per cent saturation across the ranges and possum numbers were high.
Post operational monitoring has been extremely positive. Pest species have dropped dramatically following the operation with possum densities measured between 0.25 per cent and one per cent across the two treatment blocks, and rat densities between zero and 1.03 per cent across both blocks.
Species monitoring is also a strong indicator of success with an estimated 100 kōkako fledgings from the 55 pairs in the managed area.