A unique on farm trapping project aims to reduce resident populations of rodents and improve farmers’ understanding of the link between pests, the environment and leptospirosis.

Animal health company Zoetis has teamed up with trapping company Goodnature to set up a trapping network across three Wairarapa farms to try to curb rodent numbers.

Victoria Chapman, Zoetis vet advisor, says rats on farms can be a key vector for the transmission of leptospirosis when stock ingest feed or grass that infected rodents have urinated on.

“The debilitating effects of lepto’ on humans is quite well known, but it also has a negative effect upon stock productivity in herds or flocks infected with it,” she says.

“Along with vaccination and hygiene, trapping can play an integral role in controlling a disease as problematic for livestock production as it is for human health.”

Robbie van Dam, co-founder of Goodnature, says the opportunity to set up the trap networks on the farms has a twofold effect.

“Not only are they helping to break that cycle of leptospirosis transmission but also help reduce the populations of pests that have a significant environmental impact, particularly on farms where farmers have been working to rebuild native biodiversity.”

The A24 “Chirp” upgraded traps are Bluetooth enabled. When linked to the farmers’ smartphone through an app, they record the time, day and air temperature when each pest was killed. They will also issue an alert when the bait needs renewing or the gas canister that powers the trap needs replacing.

“The farmers already have enough things on their plate during the day, and these smart traps just take some of the memory load off them.”

Martinborough drystock and cropping farmers Mark and Susannah Guscott have a network of 50 traps installed around their 800ha property, which also includes 20ha of covenanted bush. As part of the Ponatahi Eco Zone, they are aware of the impact rodents like stoats and rats have on the environment. Over the years they have used poison to control rats initially, but also possums.

“We think we have made inroads. We certainly see more native birds around than we used to,” says Mark.

He has welcomed the opportunity to extend the trap network with Goodnature and Zoetis.

“Lepto is a disease you link to cattle, and I have friends who have had it and it’s a disease that can hang around for a long time. You wouldn’t want it if you can avoid it.”

Further north at Carterton, dairy farmer Scott Dormer is also participating in the programme with traps located near the farm creek and around the farm dairy and buildings.

“In the first week one trap took out eight mice in one night.”

He welcomes the chance to nail any rodents on his farm.

“Rodents in the stock feed is something we try to avoid. They destroy the quality and spread lepto when they get into it and the cows eat it.”

While Scott has never had lepto, he knows some farmers who have.

“It’s a nasty disease and can affect you for quite a while after you first get it.”

He appreciates having traps that don’t need to be checked manually every day, and is looking forward to having a few less rodents as a result.

For fellow dairy farmer Clint Renall, anything that helps reduce rat numbers is welcome. His father has had leptospirosis, and still struggles at times with its aftereffects.

“And it has been a few years now since he got it.”

With staff on the farm, Clint religiously vaccinates his herd to reduce any infection risk, and the Goodnature traps offer a simple, self-managing solution to laying poison bait around the farm.

Goodnature’s Robbie van Dam says the farm trap project will generate some valuable data on rodent activity and trapping rates, and help in the design of future programmes.