Southland Regional Council has been left stumped after a dead wallaby was found near Gore - far from South Canterbury where they usually roam.
WARNING: Graphic image below
The wallaby was found on the side of Hokonui School Road by a member of the public on Friday.
Council biosecurity officer Dave Burgess said he believed the wallaby has most likely fallen from a vehicle after being hunted further north.
He said anyone who is missing a dead wallaby should get in touch with the council so they can establish how it got into the region.
"We are not worried if this wallaby was already dead when it got here, but we just want to be sure that these pests aren't bouncing into our region."
Mr Burgess said wallabies are causing significant problems in South Canterbury and have been identified as a pest under Southland's Pest Management Strategy.
They cause damage to native forests, compete with cattle and sheep for pasture, and are capable of reaching very high population numbers, he said.
Three pairs of wallaby were introduced to Waimate in South Canterbury 140 years ago, now there are estimated to be hundreds of thousands of them, spreading at about 50sq/km a year.
In April last year, the Otago Regional Council called for a comprehensive, incursion response, control and surveillance strategy to stop wallabies from crossing the Canterbury boarder.
Wallabies have been getting across the Waitaki River by hopping over the Aviemore Dam at night, and from there they head up and over the Hawkdun Range into North Otago.
The Canterbury Regional Council has put up a fence to stop the animals moving across the dam and has dog teams running search and destroy missions twice a year.