The discovery of two dead wallabies on Northland roadsides has set alarm bells ringing among the region's biosecurity experts.
The first was found near Kawakawa's Three Bridges on 4 December and the other a week later, also on State Highway 1 but at the Maungakaramea turnoff south of Whangārei.
It is not the first time wallabies have been reported in Northland, but the Kawakawa find is the region's first confirmed sighting of the pest marsupial.
It is possible, however, there is an innocent explanation.
Northland Regional Council biosecurity manager Nicky Fitzgibbon said staff had spoken to the man who found the wallaby but, unfortunately, by the time they received the report the animal had been fed to dogs and there was no trace left.
She was, however, confident it was a wallaby.
Fitzgibbon said trail cameras had been set up at two nearby properties as a precaution, but the surrounding terrain was not thought to be suitable for the pest marsupials.
It was possible the wallabies had been killed elsewhere and fallen from a ute while it was travelling through Northland.
Adding credibility to that theory was the reported sighting of the other wallaby carcass on State Highway 1 on 11 December.
Fitzgibbon said wallabies were found on Kawau Island, just south of Northland Regional Council boundary, and large numbers were present in the Rotorua Lakes area, North Otago and South Canterbury.
She appealed to the public for any information that might shed light on the mystery, including from anyone who may have been transporting dead wallabies into Northland or who had seen a vehicle doing so.
The incidents had been reported to Biosecurity New Zealand, she said.
Wallabies were classified as an unwanted organism due to the significant damage they inflicted on native bush, farms, crops, plantation forests, riparian plantings, biodiversity, and the economy.
That classification made it illegal to hold, move or transport wallabies without permission.
Fitzgibbon said wallabies were fast breeders, with the illegal release of a single pregnant female able to quickly create a new population threatening the local economy and environment.
She urged anyone who saw a wallaby, dead or alive, to report it online to www.reportwallabies.nz.
In 2021 and 2022 the council received reliable reports of wallabies on farmland at Waimamaku in South Hokianga.
However, despite dog searches and weeks of surveillance, no wallabies were found and there have been no further reports in the area.