Controls on the movement of fruit and vegetables in the Auckland suburbs of Devonport and Ōtara have been lifted after no further fruit fly have been found there.
The decision follows several weeks' of intensive trapping and inspections of hundreds of kilograms of fruit leading to the conclusion that there are no breeding populations of Queensland fruit fly in the Devonport area, or Bactrocera facialis (facialis) fruit fly in Ōtara.
Biosecurity New Zealand placed legal controls on the movement of fruit and vegetables in Devonport after a single male Queensland fruit fly was identified from a national surveillance trap on 14 February. There have been no further finds in Devonport.
Similar controls were placed in Ōtara after a male facialis fruit fly was found there on 18 February. There were 2 further finds on 21 February and 5 March in separate response surveillance traps nearby where the first detection was.
"To date no further adult fruit flies, eggs, larvae or pupae have been found, "says Biosecurity New Zealand spokesperson Dr Cath Duthie.
"We are satisfied that with no further detections, the Controlled Area Notices can be lifted today."
"As a precautionary measure, we will be keeping in place an enhanced network of fruit fly traps in Devonport and between Devonport and Northcote, as well as in Ōtara, for an extended period. If fruit flies are present, these traps will detect them."
The Biosecurity New Zealand signage and wheelie bins will be removed from the 2 suburbs over the next few days.
Biosecurity New Zealand and the country's horticultural industries would like to sincerely thank the residents and businesses in the affected suburbs of Devonport and Ōtara.
"You've borne the brunt of this situation with the movement restrictions and regular checking of traps on fruiting plants in your gardens and we're extremely grateful for your support," says Dr Duthie.
"I can't stress enough how vital this work has been. This particular insect pest is a significant threat to our horticultural export industry and home gardens."
The restrictions in place on the movement of fruit and vegetables and the current baiting programme in Controlled Zones in the North Shore suburb of Northcote remain in place.
The last Queensland fruit fly detection in Northcote was on 14 March and our operational response was stepped up.
"Our teams on the ground have been removing fallen fruit from backyards, inspecting compost bins, and placing bait on fruit trees to attract and kill adult flies, in particular females. The bait is made up of a protein to attract adult fruit flies, and a very low concentration of insecticide to kill the flies. It's similar to how people bait wasps in their backyards."
"The baits are toxic to fruit flies. We have taken every precaution to make sure the baits are safe around people and animals. They are not harmful to bees," says Dr Duthie.
Detailed maps of the controlled areas and a full description of the boundaries, and full information about the rules are at: www.biosecurity.govt.nz/fruitfly
Background and current situation
Single male Queensland fruit flies were found in separate surveillance traps in the Auckland North Shore suburbs of Devonport (1 single male fly) and Northcote (6 single male flies over a 3 week period). Extensive trapping and fruit monitoring has not shown any evidence of a breeding population.
The Queensland fruit fly has been detected before in the upper North Island in the past decade. Biosecurity New Zealand's staff are well practised in dealing with this situation.
Three single male facialis fruit flies were found in separate surveillance traps in Ōtara.
To manage the fruit flies that have been found, Controlled Area Notices (CANs) were issued for all 3 suburbs. This restricts the movement of certain fruit and vegetables out of the Controlled Area to help prevent the spread of any fruit flies if any are present. The restrictions are now lifted for Devonport and Ōtara, although an enhanced trapping network will continue in both suburbs for an extended period as a precautionary measure.
The restrictions in place on the movement of fruit and vegetables and the current baiting programme in Controlled Zones in the North Shore suburb of Northcote remain in place. You can download a detailed map of the controlled area and a full description of the boundaries. Full information about the rules are at biosecurity.govt.nz/fruitfly
Treating properties in Northcote for Queensland fruit fly
Why we need to use baits
The Queensland fruit fly is a major threat to New Zealand horticulture, our economy and many of the fruit and vegetables people grow at home. We don't want it to establish here.
We have taken every precaution to make sure the baits used are safe around people and animals. We apply bait mixture in fruit trees where fruit flies lay their eggs to attract and kill adult fruit flies.
What are the chemicals being used?
The bait is made up of a protein to attract adult fruit flies and a very low concentration of insecticide (called either fipronil or spinetoram) to kill the flies.
The baits are highly toxic to fruit flies, but low risk to people and pets. The amount of fipronil used in bait spray is similar to that in a flea treatment for a large dog. Spinetoram is commonly used in agriculture. Bees are not attracted to the bait.
A small amount (50ml) of bait mixture is squirted onto some of the leaves and foliage within the shady parts of host trees via a low pressure drench gun to ensure the squirt is well directed and away from any contact with fruit.
Will you tell me if my property is going to be treated?
If baiting is happening on a property, our field teams talk to households where possible (if residents are home), or leave a letter when they have visited to apply bait.
How many times will my property be treated?
Properties in Zone A of the Controlled Area will have bait applied twice in the first 7 days to any trees that fruit flies are attracted to. We will need to return to your property once a week for a further 2 weeks. If it rains, we may need to reapply sooner.
Do I have a choice about my property being treated?
We understand there may be concerns, but it's important we destroy all life stages of the fruit fly. We have legal powers under the Biosecurity Act 1993 to carry out this operation. The treatments have been chosen for both their safety and effectiveness. If you have further questions and want to speak to someone, contact us on 0800 80 99 66 or email FruitFly@asurequality.com
Can I eat fruit or vegetables that have been, or are near areas, where bait has been used?
The bait (fipronil or spinetoram) treatment we are using is being applied using the product's directions. The application method (with a low pressure drench gun) is designed to minimise the chance of fruit on trees and other plants in gardens coming into contact with the bait mixture.
If the bait mixture contacts any fruit, our staff will remove it from the tree and safely dispose of it. Unfortunately for dense trees, like feijoa, this might mean removing a lot of the fruit. As a safety precaution, you should not eat fruit from trees on your property that have been treated.
Vegetables in the surrounding garden areas will be safe to eat, as they are not targeted with bait treatments. However, we recommend that you wash your vegetables with cold tap water prior to eating.
When disposing of any fruit or vegetables, use the Biosecurity New Zealand amnesty bins provided. If you have any concerns, call us on 0800 80 99 66.
Will this operation affect my health?
The treatments being used in this fruit fly eradication programme are not expected to cause any health issues. However, if you feel you or a family member are experiencing health concerns, you should immediately seek advice from your doctor, or call the National Poisons Centre on 0800 764 766.
For specific information on the bait used in this fruit fly response, visit: www.biosecurity.govt.nz/fruitfly
For more information
If you have further questions and want to speak to someone, call 0800 80 99 66 or email firstname.lastname@example.org
Timeline: Fruit flies found in Auckland, 2019
February 14 - Single male Queensland fruit fly located in Devonport, on the North Shore.
February 18 - A different species of fruit fly, a male facialis, discovered in Ōtara, south Auckland.
February 20 - Another single male Queensland fruit fly found on the North Shore, this time in Northcote.
February 21 - A second single male facialis detected in Ōtara, only 70 metres from the first find.
February 23 - Another single Queensland fruit fly found in Northcote.
February 28 - A third single male Queensland fruit fly detected in Northcote, 270 metres from where the last was found.
March 4 - A fourth male Queensland fruit fly detected in Northcote, approximately 80 metres from where the last was found.
March 5 - A third single male facialis detected in Ōtara, 630 metres to the North of the last find.
March 10 - A fifth single male Queensland fruit fly is found in Northcote, 60 metres from where the last was found.
March 14 - A sixth single male Queensland fruit fly is found in Northcote 650 metres south of the original find.