The Ministry for Primary Industries (MPI) says it has bolstered security at the border to make sure no more Queensland fruit flies get into the country.
This comes after a call from Horticulture New Zealand for the allocation of more resources to deal with the fruit fly incursion, after the discovery of more of the insect pests.
Another male fruit fly has been discovered in the suburb of Grey Lynn, bringing the number of adult flies to four, along with 38 larvae and one pupa.
MPI chief operating officer Andrew Coleman said there was heightened security at airports for people arriving from high risk countries such as Australia and New Caledonia.
He said airport staff would assess them when they arrived, and they would either be x-rayed or go past a detector dog.
Mr Coleman said anyone declaring fruit and vegetables would be closely monitored, and travellers could expect to be questioned.
Call for more response resources
At the weekend, MPI said about 180 staff were working on the response.
"They're going to have to throw some more resources at it given what's happened over the weekend," Horticulture New Zealand chief executive Peter Silcock said.
However, changes to biosecurity screening at the border were enough at this stage, he said.
Restrictions on the movement of fruit and some vegetables out of the control zone was extended yesterday for up to two months. The control zone was set up last week, centred on the property in Grey Lynn where the male fly was found last Monday.
Minister for Primary Industries Nathan Guy told Morning Report he was confident it was a small localised population.
Listen to Nathan Guy
He said 7500 traps throughout the country were checked regularly and no fruit flies have been found outside the control area centred on Grey Lynn.
However, fruit growers are concerned that the fruit fly discoveries in Auckland will lead to a full blown infestation.
Auckland Fruit Growers Association secretary Monty Neal said the fact the insects had been found at all stages is worrying.
"From my experience, because we monitor for pests on our orchard and put traps out, just from my knowledge of doing that with other bugs and insects, when you're starting to get the whole life cycle, you're getting close to an infestation."
A large operation is underway in Grey Lynn, including trapping, spraying trees, as well as extending restrictions on the movement of fruit.