Wandering stock potentially spreading the killer bovine disease mycoplasma bovis are a threat to Northland's farming industry and must be safely fenced.
Concerns have been raised after Whangarei District Council animal control officers herded two bulls, two cows and a heifer, seen wandering near Poroti, into another farmer's paddock already containing stock.
Federated Farmers of New Zealand and leading dairy and beef farmer in Northland, Murray Douglas, said the actions of WDC animal control officers were unacceptable in light of the risk of M. bovis.
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The incident comes as the Ministry for Primary Industries step up measures to stop the spread of M. bovis by testing milk collected by Fonterra tankers on every farm. There are about 1000 dairy farms in Northland.
Tests started about four weeks ago and results are expected in December.
MPI has also started tests involving a one-off nasal swab on calves across New Zealand but refused to say if any would be carried out in Northland.
In September a Northland farm near Dargaville tested positive for M. bovis and a herd of 50 beef cattle on the property will be culled at a time suitable to the farm owner.
Douglas, who also farms at Poroti, said wandering stock were a risk to the public as well as a threat to biosecurity if they came into contact with other stock.
"I can understand why the animal control officers put the wandering cattle in that farm but in this day and age, the biosecurity risk and especially the risk of M. bovis is high.
"Perhaps the council could update their policy relative to the changing biosecurity challenges."
Douglas said if wandering stock were put into neighbouring properties, those property owners should be notified immediately.
The property owner in Poroti found out the wandering cattle were mixing with his animals the next day and managed to track down their owner after WDC could not tell him who the cattle belonged to.
WDC manager health and bylaws, Reiner Mussle, said the animals at Poroti were discovered at night and as animal control officer took the most practical by keeping them off the road as best he could under the circumstances.
Since the incident, he said WDC has been in discussion with MPI about ways of improving outdated national legislation that included creating alternative processes for containing wandering stock.
"Stock owners need to be aware of their obligations to keep their animals contained on their property and ensure that boundary fencing is stock-proof to prevent stock wandering on to roads and neighbouring properties," Mussle said.
MPI incident controller Catherine Duthie said due to the heightened biosecurity risk, farmers should take extra care to ensure their cattle were secure.
"As the main pathway for spreading Mycoplasma bovis between cattle is prolonged cow-to-cow contact mixing cattle where farmers aren't sure of their origin can be risky."
Federated Farmers of New Zealand said the incident highlighted the WDC's continued ignorance around biosecurity in the midst of a war on the deadly cattle disease.
"This is unacceptable behaviour from a council. You do not just place rogue stock in a paddock and walk away without telling anyone. Do these officers have no care?" Federated Farmers Northland provincial president John Blackwell asked.
Federated Farmers have gone to great lengths to promote safety messages to councils but they were not getting through, he said.
Far North District Council manager compliance and consents Darren Edwards said his staff did not put wandering stock into paddocks without the permission of the property owner.
The problem of wandering stock was treated primarily as a health and safety issue.
Edwards said the arrival of M. bovis in Northland has not altered the council's response to wandering stock calls.
"Where there is a clear danger to traffic, staff will put traffic controls in place. If attending an incident at night, they may ask for police assistance if required.
"The next priority is to attempt to track down the stock owner by distributing Notice to Stockowner booklets to all nearby homes. This is effective in alerting owners to the problem and is generally welcomed. The council very rarely transfers stock to its animal shelters," he said.