But one potential concern could be export growers dumping their produce on the local market, if the pest were to spread, Mr Meyrick said.
Chairman of fruit fly biology and management at Queensland University of Technology, Tony Clarke, said he suspected fruit flies could survive throughout the North Island and in parts of the South Island.
"It does have good survivability in cold areas but it's not infinite. If you are in an area with regular snow or frost the flies are not likely to survive winter."
Fruit flies could acclimatise to gradually cooling weather but did not cope well with cold snaps or long periods of extreme cold like those experienced in the far south, Mr Clarke said.
Australian growers previously used organophosphate insecticides to control the pest, but these had now been withdrawn for regulatory reasons, he said.
He said as officials here had discovered the outbreak early, the chances of eradication were good.
"The detection of single, or very low numbers of flies in New Zealand, should be seen as a sign that the system is working."
Horticulture New Zealand president Julian Raine said while many growers were concerned, they were in the hands of the Ministry for Primary Industries (MPI).
"It's really what happens from here. If it still continues to be contained it won't affect growers in other parts of New Zealand but if they find it further out then it becomes a more serious issue.
"There's not a lot that the average grower can do about it."
With the apple harvest starting it was a "critical time for pip fruit growers", especially those with export contracts, Mr Raine said.
New Zealand exports about $2.23 billion worth of fruit and vegetables a year to trade partners including Asia, the US, Europe and the Pacific.
Pipfruit New Zealand chief executive Alan Pollard said the organisation was doing its best to keep growers informed.
"Clearly we are very concerned. It's a $500 million export industry and ultimately it's our growers' livelihoods that are at risk."
Convincing our export markets that the incursion could be contained and would not affect production areas was a priority, Mr Pollard said.
"Obviously growers are concerned because fruit flies are a significant fear, particularly as an export industry. We need to convince the export market that it's an isolated risk and shouldn't have any effect on our imports."
Minister for Primary Industries Nathan Guy said he believed with the support of the public, the outbreak could be stamped out.
"It's hugely important that we keep our trade going. Some of the countries that we do have trade with have Queensland fruit fly, obviously Australia, but we want to work hard to maintain our status as being free from this dreadful pest."
New Zealand's trading partners had been alerted, he said.
"We haven't experienced any negative reaction from them, which is positive."
Mr Guy said the exclusion zone and restrictions in place around the Grey Lynn area might need to remain in place for several months. Residents with homes or businesses within a 1.5km area are being asked not to move whole fruit and certain vegetables out of the area.
An additional export restriction zone extends for 3.5km from the location of the last detection. All international passengers and their luggage are now being screened by detector dogs upon arrival.
Queensland fruit fly
¦ Queensland fruit fly is one of the most damaging fruit fly pests as it infests more than 100 species of fruit and vegetables.
¦ Hosts include commercial crops such as avocado, citrus, feijoa, grape, peppers, persimmon, pipfruit, and stonefruit.
¦ In Australia, the Queensland fruit fly inhabits parts of Northern Territory, Queensland, New South Wales and the eastern corner of Victoria, with outbreaks in South Australia.
