Bay of Plenty kiwifruit growers will be relieved no further fruit flies have been found in the Whangarei area, which could point to the absence of a breeding population.

If it is discovered the insect has established in the region it could have serious consequences for exports of kiwifruit and other horticultural products.

This morning the Ministry for Primary Industries reported that no fruit flies have been detected in traps in Zone A, or in fruit collected and examined from Controlled Area properties.

The MPI operations began after a single male Queensland fruit fly was found on April 1. The controlled area is a circular zone extending 1.5km from the location of the fly find in Parihaka and takes in areas of Parihaka, Riverside and central Whangarei.

Traps in Zone A are cleared daily and traps in Zone B are cleared and examined every three days. The first results from the Zone B traps should be available with tomorrow morning's update.

A total of 54 staff are out in the field today and around 50 staff are working on the response in Wellington.

There are restrictions on the movement of fruit and some vegetables out of a defined controlled area around whole fruit and vegetables (except for leafy and root vegetables) cannot be moved out of the controlled area, although fruit and vegetables can be carried into the area.

The restrictions are an important precaution while MPI investigates whether any further flies are present. If there are undetected flies out there, the measures will help prevent their spread out of the area.

The Whangarei Countdown supermarket in Okara Drive and the PAK'n SAVE supermarket in Walton Street are outside the controlled area and sales of fruit and vegetables continue as usual.

MPI asks that people who have bought fruit and vegetables outside the controlled area (for example in these supermarkets or the weekly local farmers market), but need to travel through this area, ensure the produce is in plastic bags for the journey.

Full information about the Controlled Area and the restrictions, including maps and full instructions is at: http://www.mpi.govt.nz – follow the fruit fly button.

MPI is running an extensive response trapping network, as set out in an internationally- validated standard, to lure any fruit flies that may be present. Gardens and rubbish bins in the controlled area are being inspected for any signs of fruit flies.

The controlled area comprises two zones – Zone A extends 200m from the site of the detection and Zone B goes from that 200m boundary out to 1500m.

There are now 115 response traps in Zone A and 195 response traps in Zone B. The original fruit fly was found in a surveillance trap that is part of MPI's national surveillance programme. There are 13 of these routine surveillance traps in the controlled area.

Residents in the controlled area have been advised to dispose of all fruit and vegetable waste through in-sink waste disposal units (where they have them) or in bins provided by MPI. There are 215 of these MPI disposal bins in the controlled area and at other high-risk sites. MPI is emptying the bins and safely disposing of the material.

MPI has field laboratory facilities in place examining fruit collected from gardens in the controlled area and also to identify any suspect insects collected.