A fifth Queensland fruit fly has been found today in a trap within the controlled area in the Auckland suburb of Grey Lynn.
The Ministry for Primary Industries said the male fruit fly was found today.
MPI said it expected to find further flies close to the affected property where the initial fruit fly was found as the response to the incursion progressed.
The Ministry remained confident it was an "isolated population" which would be eradicated.
Four male fruit flies have been caught in traps, and a single unmated female was located at a residential property on Friday. One pupa and 39 larvae have also been found.
MPI field work continued today to focus on the surveillance trapping system as well as workers applying insecticide bait throughout the controlled area.
Residents have been informed about the controls and gardens and rubbish bins are being inspected.
Insecticide bait has been applied to fruiting trees and plants throughout the controlled area.
MPI said the bait application may appear like spraying - as it is applied by operators using backpacks and spray-like wands. However, spraying of insecticide has only deployed at properties where fruit flies or their larvae/pupae have been found.
About 126 field staff were working on the ground today and about 80 people were working on the operation in MPI's Wellington Head office.
Meanwhile, Pasifika Festival, which more than 80,000 people flocked to last year, may have to shift from Western Springs Park just three weeks out from the event because of the potential risk of spreading the pest.
A spokesman from Auckland Tourism, Events and Economic Development (Ateed), which organised the festival, confirmed it was in discussions with the Ministry for Primary Industries about a possible move from the park, ahead of the two-day event in March.
However, the decision was in the hands of MPI, the spokesman said.
It is understood MPI initiated the discussions because Western Springs Park sits inside the 1.5km radius exclusion zone, where tight controls on the movement of fruit and some vegetables are in place.
New Zealand First spokesman for Pacific Island affairs Pita Paraone said the Government needed to "take responsibility for the threat of cancellation".
"If the Pasifika Festival cannot be held at Western Springs Park because it is within the affected fruit fly outbreak area, then the Government needs to come to the party to support the festival's relocation," he said.
"The reason we are facing this situation at all is due to the National Government not putting enough money and resources in to New Zealand border security to make the country bugtight.
"This is the Pacific community's weekend to really shine, and any cancellation can only be put down to Government negligence at our borders."
He urged the Government to "do everything possible to ensure this wonderful celebration of New Zealand's Pacific culture and heritage goes ahead".
A number of alternative venues were being looked at, the Ateed spokesman said.
Pasifika Festival is billed as the "biggest celebration of Pacific Island culture and heritage in the world". The weekend event is due to take place on March 14-15, bringing the "sights, sounds, tastes and colours of the Pacific" to Auckland, with 11 Pacific Island villages and more than 1000 performers showcasing the best of Pacific Island music, dance and culture.
By the numbers:
307 traps laid in Zone A
193 traps laid in Zone B
126 staff on the ground
80 staff in Wellington
544 disposal bins in controlled area
1300 kilograms of produce waste collected from bins daily
36.56 kilograms of fruit sliced and inspected by MPI scientists yesterday