The Department of Agriculture's head of biosecurity Lyn O'Connell said the majority of items seized in the last six months were footwear or sporting equipment contaminated with soil or plant material.

"The arrival of international flights means maintaining biosecurity vigilance is increasingly important for Canberra, as the capital is exposed to a range of potentially new risks," Ms O'Connell said.

Some of the items seized by Customs include a collection of food and several ornaments, including a pine cone kiwi bird and a Jean-Michel Basquiat-esque painted mask.

"All of these items are a biosecurity risk because they could be carrying harmful plant pests and diseases that have the potential to adversely affect our plant health and environment," Ms O'Connell said.

"For instance, if passengers bring in an apple it could carry pests like fruit fly, which could seriously damage our $556 million apple industry and more broadly our horticulture industry that is worth more than $9 billion."

Flights were assessed before landing based on the risk they posed but a spokesperson for the Agriculture Department said it was still up to the public to do the right thing.

No quarantine infringement notices have been issued at Canberra Airport since services started.

The airport shares biosecurity measures with airports in Broome and Townsville, with similar arrival and risk patterns.

"We are not on the lookout for specific biosecurity concerns, we focus all our efforts on identifying and intercepting any biosecurity risk items," an agriculture department spokesperson said.

The department estimated biosecurity checks saved the average Australian farmer $17,500 per year.

In 2015-2016, the department screened 4.1 million passengers at Australian international airports, seizing 270,000 items and issuing 3700 quarantine infringement notices.