The Mercury has heard at least one report of the bugs being found on cargo at Port Kembla.

The bug, officially called the brown marmorated stink bug, is "an exotic pest of considerable biosecurity concern to Australia's agriculture industry", according to an industry notice from the Department of Agriculture released on Thursday.

"Juveniles feed on, and severely damage, fruit and vegetable crops, and adults can enter vehicles, homes and factories in autumn months in large numbers looking for warm places to hide and overwinter," the notice stated.

The source has been identified as the US port of Savannah and the volume of pests is so great the Department of Agriculture is requiring all cargo to be treated before leaving.

Once the cargo lands in Australia at ports like Port Kembla, it will undergo an inspection, said a department spokeswoman.

"Due to increased detections of brown marmorated stink bug pest on cargo coming from certain ports in the eastern United States, the department is requiring inspections of trucks, other vehicles and automotive parts prior to discharge," the spokeswoman said.

"Where an unacceptable biosecurity risk is identified, the department requires a treatment that is effective against this pest to be applied."

The treatment includes fumigation which is applied as a fog throughout the deck of the cargo vessel.