A Tauranga kiwifruit grower is calling for cruise ship passengers to strictly face the same warnings and fines over bringing fruit into New Zealand as air travellers in the wake of a second fruit fly find this week.

'There's not enough information telling passengers it is unacceptable to take fruit ashore, and no penalty for those caught doing so,” says Vern, who has just returned from an Australia to New Zealand cruise.

A Tauranga kiwifruit grower is calling for tighter restrictions on passengers on cruise ships bringing in fruit.

Like other fruit growers, Vern is concerned about the latest male fruit fly discovery in Whangarei about 400m from the January discovery, fearing the insect could be found in the Bay of Plenty too.

'It's unbelievable how easy it is for passengers, 2500 of them on a ship, to walk shore with little or no checks and those who are caught just have the fruit confiscated – there's no instant fine like at airports,” says Vern.

This season 80 cruise ships visited the Port of Tauranga and while some passengers have been checked by Ministry for Primary Industries' inspectors with dogs, Vern says penalties need to be imposed for those taking fruit ashore. 'If a few were fined $400 that would have an impact.”

Yesterday, SunLive accompanied MPI officials undertaking routine security clearance checks on 2009 passengers disembarking the Dawn Princess at Mount Maunganui, with the help of one of the ministry's 30 national dog squads. The beagle made three fruit finds on passengers departing the vessel. To view the action, click here.

Vern says the cruise he and wife Barbara were on was greeted by an MPI officer and a beagle at its first port of call in Dunedin. 'She told me the dog detected lots of people with fruit in their bags, but as far as I know no one was fined.”

Hugh Moore, a kiwifruit and avocado orchardist and packhouse operator in Katikati, says he accepts the latest fruit fly find is not related to the one in January, but he's not altogether surprised another insect has turned up.

'This is the time when a lot of pleasure boats start returning from the Pacific – and Opua [in the Bay of Islands] or Whangarei is often their first port of call.” Fruit on board those vessels could carry unwanted insects like fruit fly, says Hugh.

'I don't think these vessels have been policed as they should be. People on those boats should be aware that they can't bring fruit and vegetables into New Zealand but many probably aren't and I'm not sure that there are secure facilities for disposing of fruit and vegetables at the marina like the bins at the airports.”

Yesterday, Horticulture New Zealand chief executive Peter Silcock came out saying New Zealand needs to urgently look at how it is managing its biosecurity risk following Tuesday's discovery, while Kiwifruit Growers Inc's Neil Trebilco says there's heightened concern over the find as the kiwifruit harvest is underway – and if a population of the insects is found, it could impact on exports.

Hugh says the discovery of the fruit fly again illustrates the need for horticultural industries to be part of the Government Industry Agreement on biosecurity – because by signing up, industries will have an influence on what happens at borders.

The MPI operation mounted after the discovery of a single fruit fly in January cost close to $1 million but Hugh says it was cheaper than trying to eradicate the pest had it become established.

The latest detection shows the MPI trapping methods work and now one insect has been found, hundreds more traps will be put in place.

Hugh is hoping no more will be found. 'We need to demonstrate to the rest of the world that we don't have a breeding population here.”

If such population was found, it could see some countries close their borders to the import of New Zealand fruit and vegetables.