We were privileged to have Dr Sabine Perrone share a small amount of her knowledge of the fascinating topic of biosecurity and its importance in a fast-changing world.
Sabine explained how the term ‘Biosecurity’ originated in USA, and how there is now an increasing need to have systems in place to prevent importation of pests and disease. This is a vitally important aspect of international trade.
These days we can transport goods much faster and further than before. Whereas most pests would not survive a long sea journey on a sailing ship, modern transportation has created an environment for easy transmission of pests and diseases.
Australia is fortunate because it brought in clean seed when cropping began after European settlement. In our quest for higher crop yields, we have produced monocultures. Unfortunately, this has made crops more vulnerable to pathogens. We also import lots of goods.
Sabine also explained that biosecurity starts in the originating country, and it is impossible to import only completely clean produce. Big volumes at the port of entry mean can’t check everything, so we also need a second line of defence to detect anything that has slipped through port-of-entry checking.
Eradication of disease and pests is very expensive. Plant viruses are particularly challenging because they are often mistaken for other symptoms and so are difficult to detect. It is often necessary to control the vector (eg insects) rather than the virus itself, and in many cases it may not be possible to completely eradicate the disease.
A lot of pests and diseases come to Australia but do not establish. A good example is the European bumblebee in Tasmania. This insect was illegally introduced because of its effectiveness as a pollinator – the bumblebee vibrates at just the right frequency to release pollen. In Europe bumblebees are commonly used to pollinate crops. They are also very good at pollinating weeds, especially European weeds like blackberry and foxglove. The result is that in Tasmania there are a lots of European weeds, helped along by the bumblebee. Bumblebees are not good flyers but are good at getting in cars and crossing Bass Straight via the ferry. Fortunately we have never found a significant bumblebee population in Victoria.
Ants are example of an insect that establishes well in Australia. Eg fire ants in Brisbane. The native ant population has been displaced by urban development making it easier for fire ants to establish. Fire ants completely destroyed a lady’s garden in Brisbane before their presence was recognised by authorities.
Sabine highlighted that once a pest has established a population in the environment it is very difficult and expensive to eradicate the problem. New Zealand has a fantastic history of eradication. Australia is too big to completely understand what is in the environment.
We need first to answer ‘Should this organism be here?’ If cost of eradication is too high suppression may be the best option.
A pdf copy of the bulletin can be found here. RC of Ivanhoe 19 August 2020