Horticulturists are being urged to be on the lookout once more for traces of fruit fly

Biosecurity New Zealand says the male Oriental fruit fly was trapped in a Birkdale backyard on Auckland's North Shore yesterday morning.

Officials have since ramped up inspections within the discovery zone, as six weeks of controls on fruit and vegetables begin.

Horticulture New Zealand chief executive Kate Scott, says all those in Birkdale are being asked to comply with all instructions.

She says everyone also has a collective responsibility to ensure they look out for unknown species and follow official directions.