Back in the 1950s, a group of wallabies turned up at Wainui Station... and never left.
Before farmer Walter Cameron was allowed to use poison on the pesky marsupials, a hired gun was killing up to 3,500 a year.
Walter remembers first seeing a wallaby on his family's 12,000-hectare hill-country property when he was still in nappies.
A few years later, he was allowed to go hunting for them with his father.
"I can remember shooting my first wallaby 60 years ago and they've really ballooned since that time," he tells Country Life.
"The more sweeter you get your country, the more wallabies you're going to get."
For farmers, one of the main issues with wallabies is they eat quality feed that's intended for sheep, which can have a big impact on stocking ratios and lambing rates, Walter says.
"Three wallabies to a sheep, that's how much they eat."
He reckons having wallaby-free areas on the farm can increase returns by $50,000 or $60,000 depending on merino wool prices.
Now that poisons are being used to control the pesky marsupials, Walter feels like they are starting to get on top of the issue.
As part of MPI's National Wallaby Eradication Programme, pellets of the poison 1080 have been dropped onto Wainui Station. For Walter, this has been a game-changer.
"When we poisoned, it enabled us to run another 1,000 or 1,500 stocking units (sheep)."
He'd like other landowners with wallaby-ridden properties to follow suit and apply for a 1080 drop, but is aware some people aren't keen on having the controversial poison on their property.
"Ï fully understand those people's feeling about what it does but the thing is we're not dealing with a natural animal, we're dealing with an introduced species into New Zealand that's also having an impact on our native plants.
"There are still thousands of wallabies sitting around on this land and if left unchecked they are going to create a real issue in future years," he says.