AuthorTom Rose,Publish DateMon, 20 Jul 2026, 11:45am
New Zealand’s largest egg supplier is putting hundreds of thousands of free-range chickens into lockdown after the deadly bird flu virus was detected in the country for the first time.
Mainland Poultry, which supplies nearly 40% of the country’s eggs, has taken the precautionary step of isolating more than half a million free-range laying hens while officials work out the extent of the disease’s spread.
While there have been zero cases of bird flu identified in commercial poultry flocks, and meat and eggs remain safe to eat, chief executive John McKay said the two detected in wild birds for the first time last week had prompted them to try to mitigate the risks.
McKay, who is also the chair of the Egg Producers Federation (EPF), told Ryan Bridge TODAY the nationwide agribusiness had just over 1.3 million hens, with around 550,000 of those farmed as free-range.
Free-range hens are usually given the freedom to spend much of their day outside and can interact with other wildlife, so McKay said Mainland Poultry staff had a “pretty busy weekend” closing off the pop holes in barns until more is known.
“The birds naturally come in in the evening. They come in to roost and have their final feed before they go to sleep,” McKay said.
Mainland Poultry has isolated over 550,000 free-range hens as a precautionary measure after New Zealand’s first two cases of the H5N1 bird flu strain were detected last week. Photo / 123rf
“In the morning, [the pop holes] aren’t opened as per usual … so the birds are temporarily housed inside those barns for their welfare.”
McKay said free-range eggs made up about 45% of New Zealand’s total egg market, so there was clear consumer demand.
Mainland Poultry would continue to maintain good on-farm biosecurity, even ramping up some measures, as McKay said it was crucial for protecting their hens and businesses.
“Obviously, we care deeply about our birds,” McKay said.
“Let’s better understand the risk, understand where it might have spread or where it hasn’t spread, and then based on better understanding that risk, we can then make good decisions about what we do with those birds going forward.”
New Zealand’s first known case of the H5N1 strain was recorded on Wednesday in a wild brown skua found on Lower Hutt’s Petone Beach, with a second detection in a native kāhu, or swamp harrier, in the Wairarapa announced Friday.
In an update yesterday, MPI’s chief veterinary officer Dr Mary van Andel said no new cases of bird flu had been found since, but they had received a surge in reports about dead or sick birds since the public notification and would be continuing to investigate each one.
Authorities hadn’t found any evidence of widespread transmission or mass mortality affecting wildlife either, she added.
“We have staff on the ground over the weekend carrying out checks in some areas of Wellington’s south coast and Wairarapa,” van Andel said.
“We continue to have a strong response from the public about unwell or dead birds they have seen, and we consider every notification and triage any suspected cases of avian influenza.”
Van Andel urged people not to touch or move the birds they encounter.
“If you see three or more sick or dead wild birds in a group, report it immediately to the exotic pest and disease hotline on 0800 80 99 66 from anywhere in New Zealand or online at report.mpi.govt.nz.”
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