Biosecurity workers are growing more confident that a Queensland fruit fly found in Whangarei is the only one to have made it into the country.
A trapping system and restrictions on moving fruit and vegetables were activated after a sole male fruit fly was found in a surveillance trap near the Town Basin on Tuesday. The insect pest is considered one of the biggest threats to New Zealand's $4 billion fruit and vegetable export industry.
On Saturday, Ministry for Primary Industries (MPI) staff laid 162 extra traps around Whangarei to determine whether the fly was part of an infestation, in addition to 83 traps set on Thursday and 90 that are permanently in place.
By Sunday morning no more of the flies had been discovered in the permanent traps and those laid on Thursday, while results from the extra 162 were expected on Monday.
MPI deputy director-general Andrew Coleman said a final all-clear cannot be given until a fortnight after the initial find.
"It is a two-week clearance that we need, that's the international standard. As each day goes by we'll become more confident and only after that two week period will we be able to say conclusively that we've retained our pest-free status for fruit fly."
He said ministry staff have also begun collecting fallen fruit, which lab workers will analyse for signs of eggs or larvae.
Mr Coleman said the Whangarei community had been very supportive, placing a total of 250 kilograms of produce in bins for disposal or testing in the two restricted zones.