What is Biosecurity?

Biosecurity is the concept of protecting the environment from invasive pests and diseases. Biosecurity covers three areas of intervention - exclusion, eradication, and pest management. These different levels of intervention can be used by themselves or combined effectively to manage any plant or animal pests.

Any plant or animal has the potential to become a pest when introduced to a new environment. The reason is that as you may not know how it will behave in the new environment. In one country a plant could be economically beneficial and in another it can be considered a pest. Gorse is used as boundary and hedge plants in Scotland to great advantage. In the warmer New Zealand climate gorse rampant weed and is a major problem for farmers.

What makes an animal a pest? The possum in New Zealand is a problem as it can attack native plants, like the pohutukawa. It can attack the eggs of some of New Zealand’s endangered bird species. The possum is also a known vector for Bovine Tuberculosis.

Plant species known as invasive species or weeds can out compete, displace and threaten native flora and affect farm pasture. In New Zealand, Gorse is a good example of a plant that affects farm pasture and costs landowners a lot of money to control.

Excluding pests can be achieved on a national scale through legislation for screening and inspection services. This is achievable in some countries like New Zealand and Australia as there are no land borders to control and the distance from other countries reduces the natural spread of animals and plants without human intervention.

Islands, peninsulars and areas with some form of natural border or man made borders can mean that eradication programmes may be successful. A programme to prevent the reintroduction of unwanted plants or animals can be put in place. When looking at physical means of excluding pests, this can be achieved with predator fencing and chemical barriers. Once the barriers are up a programme to remove all current pests within the area can be implemented

Eradication may be the preferred option but may not always be practical to achieve. In these cases pest management control programmes may be the most cost effective way of reducing pest populations and the associated risks. Eradication and pest management plans can be achieved through, mechanical removal, chemical treatment, trapping or shooting. All these methods are dependant on what needs to be eradicated or controlled.

Pest plants and animals can be difficult to control. Plant control and Animal control programmes can last over many years depending on the population density of the plant or animal pest. For some plants the continual threat can come from the potential seed bank in the soil. This means when a programme is implemented it must be continued with for the benefits to be felt.