The Big Tick Day Out – Top of the South Style - Ginny Dodunski | Issue 224 | September 2026

The Big Tick Day Out – Top of the South Style - Ginny Dodunski | Issue 224 | September 2026

The Big Tick Day Out – Top of the South Style

On a day threatening snow at St Aranud, where one would have imagined tick nymphs on pasture to be turning up their toes, 27 deer farmers from across Tasman and Nelson met at the Alpine Lodge for the second edition of the ‘Big Tick Day Out’ to look at ways of getting ahead of tick challenge on their farms, both this year, and into the future.

The afternoon integrated on-farm experience, tick life cycle basics (know your enemy!) science, regulation, and possible future control options, both on the animals and on pasture.

Background work

In an initial ‘what were you hoping?’ session, farmers indicated they were after a clearer understanding of the tick life cycle, whether they were currently using the most effective prevention plan, managing residues, and hearing what’s working on farms facing heavy pressure.

It appeared there is wide variation in tick challenge across the region. Some had never seen ticks on their deer, others reported seeing nypmhs from late winter, and on the worst farms, fawns and velvet suffered high adult tick burdens in late spring if animals were left untreated.

Current control methods ranged from regular Flumethrin, use of tick tags, avoiding rank pasture, and using other species on the farms (sheep and cattle) as ‘tick vacuum cleaners’ prior to grazing susceptible deer in paddocks.

Colin McKay (Elanco Animal Health, and NZ’s ectoparasite ‘guru’) helped farmers work through a tick life cycle exercise. Ticks have 3 life stages (larvae, nymphs and adults), each stage spending a short time on an animal to get a blood feed before dropping off into the pasture. Ticks spend long periods off‑host and have the ability to cycle multiple times per year. In addition, female ticks can produce eggs without a male in sight. Thus numbers can build very quickly!

While in the pasture, ticks prefer lots of cover, and high humidity. Areas with rushes have particularly high numbers. They jump onto the host in response to movement, and CO2 from the animals’ breath. Ticks have no eyes! Dragging a pale-coloured towel across the pasture is a method that researchers use to estimate tick pressure.

The key message was simple - Ticks are only on deer for about four weeks of their year, so effective control must target both the animal and the environment.

Current control options – strengths and limitations

The room explored all available tools: flumethrin pour‑ons, older sheep dip and environmental fly control chemicals that have some tick activity, tick tags, pasture management, grazing strategies, and quarantine practices.

For Flumethrin, correct application technique and retreatment intervals were emphasised. It is common for the interval between Flumethrin treatments to be too long. The original published work on this method of control was limited but indicated that 3-4 week intervals gave best control. No animal treatment method can remove every single tick.

Pasture treatment was discussed – in the ‘bad old days’ DDT and Diazinon were highly effective against ticks but are no longer an option for safety reasons. Positive experience using ammonium sulphate on pasture from one Northland farm has been shared in Stagline previously. Further work to validate this approach would be very useful.

Practical farmer experience

Ian Bristow beamed into the meeting from Kaipara, described living with ticks his entire farming career in Northland. His farm was part of the original tick‑tag registration trials, and he has used tags on breeding hinds ever since. Tags protect fawns through grooming and mothering behaviour, reducing early‑life losses. Ian recalled early days of extreme pressure, including applying insecticide directly to newborn fawns.

Kim Rowe, farming locally, explained how he uses tick tags on his velvetting stags. Tags reduce yarding and handling, avoiding multiple pour‑on treatments and risk of velvet damage.  They are removed in February. His stag block can develop longer, ranker pasture – a known risk factor for higher tick numbers – so any animals leaving that block are treated before moving elsewhere on the farm.

Both emphasised that effective treatment early in the season (prior to seeing lots of adults) was key to limiting a population explosion later.

Research and regulation – what’s coming?

Emil Murphy from DINZ, and Luis Carvallo, parasitologist from BSI, outlined ongoing work on tick ecology and future control options. Biocontrol research by BSI is focussing on treatments that may be applied to pasture. There is also initial work investigating possible vaccine options, through better understanding of local tick genetics and their microbiome.

Meg Moffat from MPI provided an update on flumethrin residue detections in the North Island. Reassessment of the withholding periods for Flumethrin is currently underway; it is likely that the nil meat withholding period will be changed. This will require extra planning if using Flumethrin on velveting stags, or on yearlings that are close to slaughter weight.

While the Big Tick Day out was not able to provide a ‘silver bullet’ for on-farm tick control, farmers left with a better understanding of the biology of ticks and more effective use of available control options.

For more information about on-farm tick management, see https://www.deernz.org/assets/Deer-Facts/DeerFact_Ticks_Web.pdf