Yellow-legged hornets in Auckland

Risk to New Zealand from hornets

The yellow-legged hornet is a biosecurity concern and classified as an unwanted organism due to its potential impact on honeybee and wild bee populations.

It primarily feeds on bees, wasps, and flies. It may compete with native insects and birds for food, and it has a painful sting.

About the hornets found in Auckland and our response

Yellow-legged hornets have only been detected in Auckland. We believe it’s unlikely they are present outside this area. However, Biosecurity New Zealand is closely monitoring the situation and is encouraging people to remain vigilant and report any suspected hornet or nest sightings.

A Technical Advisory Group (TAG) is supporting the response. Its members are a mix of national and international experts, many of whom have direct operational experience dealing with the yellow-legged hornet in areas it has been present in Europe.

The group's recommendations are shaping Biosecurity New Zealand’s ongoing strategy.

Key actions include: 

• setting up a surveillance zone out to 11 km from hornet detections containing protein and carbohydrate traps and feed stations, to locate hornets to track to nests
• working closely with more beekeepers for enhanced surveillance around hives – over 575 registered apiaries within the 11 km zone
• deploying a field workforce of 50 plus staff per day to carry out detection and removal
• using advanced radio tracking technology from the Netherlands to trace hornets back to their nests
• hosting specialists from the UK’s hornet response team to train staff and advise on programme delivery.

Hornet trap locations and detection area

Download the map to print it [JPG, 2.8 MB]

Use of insecticide bait

In March, we began deploying a new tool to eradicate yellow-legged hornets – a protein bait that contains insecticide.

We're putting the blue-coloured bait, called Vespex, in bait stations. The bait attracts hornets, which collect the product and take it back to their nest, poisoning the whole colony.

This insecticide is used very successfully against wasps but is harmless to honeybees and New Zealand native wasps. It has has low toxicity to mammals, including people, dogs and cats, and birds.

If you see one of these bait stations, do not touch it.

Fact sheet: Yellow-legged hornet bait stations [PDF, 804 KB]

Vespex bait station attached to a tree.

Tracking stations: don't get too close

Biosecurity New Zealand has placed hornet feed stations around the surveillance zone to attract hornets that can then be tracked to nests. We call these "tracking stations".

The stations help us detect hornets, observe their movements, and track them back to nests that can then be destroyed.

We're using a sugar-based lure to attract hornets. The lure is not toxic to humans or animals. 

Tracking stations are in open areas near hornet activity and regularly monitored by trained staff. 

Avoid tracking stations 

If you see a tracking station: 

• be aware of wasps and hornets in and around it, and keep your distance to avoid stings 
• do not touch or disturb the station or its contents.

Tracking station fact sheet [PDF, 1.1 MB]

Other methods we're using to track and trace hornets

In addition to the tracking stations, other ways being used to locate and destroy nests include:

• targeted ground searches
• further trapping and bait stations
• visual tracing
• radio tracking. 

How you can help

The best surveillance tool we have right now is for people to report any sightings of suspected hornets or hornet nests.

When looking for hornets and their nests, check common nesting areas such as under roof eaves of your house, sheltered entrances, wooden structures, carports, under wooden decks, sheds, and outbuildings. Larger, secondary nests are typically high in trees.

Also check your boat, caravan, or campervan before heading away with them to avoid moving nests around. When gardening, look out for signs of hornet activity and take care not to disturb their nests.  

Video: Learn where to look for yellow-legged hornet nests – YouTube (1.45)

What to do if you think you've found a nest

Don’t attempt to remove or control a suspected hornet nest yourself, or spray a hornet or nest with insecticide. It is very important for Biosecurity New Zealand to know where the hornets are active. Any attempt to control them risks pushing them away, making it difficult to find them.

We appreciate that taking photos can be hard, as the hornets are strong flyers, but images are the best method for us to assess the valuable observations made by the public.

If you think you have found a hornet or its nest, take a clear photo and report it:

• by calling our exotic pest and disease hotline on 0800 809 966
• by emailing us at info@mpi.govt.nz
• online at report.mpi.govt.nz – if you use this method, ensure that you select the 'suspected yellow-legged hornet’ option from the dropdown list.

Homemade traps

We know many people want to help by setting their own traps. These may be effective in attracting hornets and other flying insects, but significant bycatch of other insects should be expected. 

We have created some easy-to-follow instructions for building a simple homemade trap.

How to make a homemade hornet trap – Fact sheet [PDF, 833 KB]

A suggested bait formula to add to your trap is 400 g of sugar, 10 g of yeast, and 1 litre of water. You can also add 100 ml of beer to this mixture.

We recommend you change this bait every 3 weeks.

It is important to closely monitor any homemade trap – check them at least once a week. It helps to be familiar with local wasp species that are not a concern in this response.

If you do capture a yellow-legged hornet, report it and do not release it. Because it is an unwanted organism, it is an offence to release this pest.

Know the difference between hornets and common wasps

From left to right, biggest to smallest: 1 Yellow-legged hornet, 2 German wasp, 3 Asian paper wasp, 4 Australian paper wasp.

If you make and install a homemade trap and believe you have caught a hornet, take a clear photograph and report it online or by calling 0800 809 966. Do not handle live hornets.