Topic about Biosecurity

Biosecurity is about protecting natural and physical resources and human health from pests and unwanted organisms. This is done through exclusion, eradication, and pest management. All are different levels of intervention that can be used by themselves or more effectively in combination.

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. Gorse is a good example of a plant that affects farm pasture in New Zealand.

The exclusion of 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. The distance from other countries also reduces the natural spread of animals and plants without human intervention.

On a smaller scale – 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.

Eradication may be the preferred option but may not always be practical to achieve, hence 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 several different means depending on what needs to be eradicated or controlled. Various methods used are; mechanical removal, chemical treatment, trapping or shooting.

Pest plants and animals can be difficult to control. Many Plant control and Animal control programmes will run over many years depending on the targeted pest species. The key to success in many of these programmes is the consistent and continual running of the programme. For an animal programme this may have include an array of bait stations with periods of intense trapping to monitor the situation. If the programme is stopped however, the benefits that have been achieved would be quickly lost with reinvasion of the pest.