Brown marmorated stink bug

Image of a brown marmorated stink bug

There has been a detection of the exotic pest, brown marmorated stink bug (Halyomorpha halys), in Western Sydney.

Live bugs were found in electrical equipment that had been imported from Italy. Officers from the NSW Department of Primary Industries and the Department of Agriculture Water and Resources responded to the detection. The equipment and the container they were in, are under biosecurity control.

The premise will be treated by fogging with an insecticide for a period of three weeks, from the time of the initial detection.

NSW DPI is conducting surveillance and has set traps in the vicinity of the warehouse. Foliage around the warehouse has been treated with pesticide as a pre-caution. 

Following further surveillance, no brown marmorated stink bugs have been detected outside of the affected property.

The Consultative Committee on Emergency Plant Pests (CCEPP) continues to meet in response to this incident. A response plan is currently being considered by the committee and will soon be provided to the National Management Group for endorsement.

Import conditions

The Australian Government Department of Agriculture and Water Resources already has robust import conditions in place for goods arriving from countries where brown marmorated stink bug is present.

Every year the department reviews the import conditions in time for the brown marmorated stink bug season which begins in September. 

These particular bugs seek out a place to hide over winter in the northern hemisphere and often congregate in items where they are sheltered.  For this reason, they are most likely to arrive in Australia between September and April.

In previous years they have mostly been associated with break bulk cargo arriving from the USA. Break bulk cargo are items like vehicles and machinery that cannot be transported in a container.

In addition to the measures in place for the USA, this year new measures were put in place because of the bug establishing in Italy.  The import measures will be further strengthened in light of the recent detection.

The department is working with the Italian authorities as part of these activities.

Biosecurity and reporting


Anyone who works around or receives imported goods should always be vigilant for pests which can be attached to containers, within the goods of the container or to other goods like machinery.

If you notice any bugs or other pests, don’t remove the contents of the container, shut the doors and don’t allow the container to be moved

Phone the See. Secure. Report Hotline on 1800 798 636 or report online. This will put you in touch with the Australian Government Department of Agriculture and Water Resources who manage the biosecurity aspects of imported goods.

Local residents/farmers

Residents in the vicinity of the affected warehouse have been contacted by officers from NSW DPI or provided with relevant information.

If you think you have seen brown marmorated stink bugs on your property or in public places, phone the NSW DPI on 1800 084 881.

The most effective way to detect brown marmorated stink bugs is by visually inspecting host plants. They are large bugs that give off a strong and bad odour when disturbed.

About brown marmorated stink bug

Brown marmorated stink bug is a significant threat to agriculture due to its wide host range and the damage it can do to vegetable crops and fruit and ornamental trees. It is known to feed on more than 300 hosts, including agricultural crops such as nuts, grains, berries, cotton, citrus, soybean and some ornamental and weed plant species. 

While feeding, the bug’s saliva causes significant damage to plant tissues.

The bug is not a risk to human health but it is regarded as a nuisance pest because it seeks sheltered places to overwinter such as inside homes, vehicles, machinery or sheds, often in large numbers.

The brown marmorated stink bug is a pest that opportunistically uses cargo containers and freight vehicles to hitchhike across country and overseas.  The bug’s capability to hitchhike and fly, and feed on a wide range of plant hosts, enables it to rapidly spread into new territories.


Brown marmorated stink bug adults are medium-large (12-17 mm long). They are mottle brown in colour, and have a shield shaped appearance.

There are five nymph stages that range from less than 3 mm to 12 mm long. The nymphs are orange and black when they first hatch but quickly develop a similar colouration to the adults. The juvenile, or nymphal stages, cause the most damage.

Eggs are cream to yellow-orange and approximately 1.6 mm long and laid in clusters on the underside of leaves.

They can be confused with a number of other brown coloured stinkbugs that are present in Australia. There is a comprehensive identification guide on the Department of Agriculture and Water Resources website.

Brown marmorated stink bug is native to eastern Asia (China, Japan and Taiwan) but was introduced to North America in the mid-1990s and more recently to Europe, where it is rapidly becoming a serious pest.


At this stage there are no expected domestic or export trade impacts due to this detection.

The brown marmorated stink bug is unlikely to be associated with commercial fruit because it is a large active insect that would be readily disturbed by harvest and packing processes.

This bug is well established in many regions of the world including China, Europe and the USA, where it is not considered to be a quarantine pest.