#rawideas

Raw Ideas by sandracaleffi

Invasive species often become pests competing for resources, preying on natives, damaging ecosystems and compromising the economic productivity of agriculture, just to list a few. Additionally these impacts are often ongoing and extensive.  Increasing globalisation has lead to an increase in invasions by new species around the world and Australia is no exception (Fridley et al. 2007). An invasive species is a species that is present in a habitat as a result of human activities, beyond its accepted normal distribution and which threatens valued environmental, agricultural or other social resources by the damage the species causes (Sandlund et al. 2001). There are examples of invasive species from every order that invade and impact upon every ecosystem for example diseases, fungi and parasites, feral animals, insects and other invertebrates, introduced marine pests and weeds (Andersen et al. 2004).

Invasive species have a major impact on Australia's environment, threatening its unique biodiversity and reducing overall species abundance and diversity. Many invasive species were deliberately introduced and have arrived in Australia since European colonisation (Gherardi and Angiolini 2004). An example of this deliberate introduction is the multiple species of trout that were introduced as game fish, or the American Minnow Pimephales promelas (Mosquito Fish) which was introduced in the hope it would eat mosquito larvae and rid our cities of mosquitoes. Another well-known and perhaps considerably more destructive example is the Cane Toad Bufo marinus that was introduced in the 1930s. This alien species was introduced to help sugar cane farmer control a native beetle that feeds on their crops (Gherardi and Angiolini 2004). The toad had little impact on the beetle, but it has had a very significant impact on many native species including but not limited to native snake species. 49 species of native Australian snake taxa are at risk of toads(Phillips et al. 2003). Additionally many introduced foreign grasses have become major weeds after introducing them for the purpose of improving pastures(Phillips and Shine 2006).

There are a number of methods that have been developed to attempt to minimise or illuminate the impacts of invasive species including biological controls and culling permits. However, previous studies show the lack of ability to prevent invasion and minimal success in eradicating or effectively managing these species it is apparent that alien species are, at least for now, here to stay. Therefore I am suggested that that the best way to respond to the impacts of alien fish, that are already present and prevailing in Australian waters, is not to simply manage these populations but work towards strengthening our own native populations. There needs to be a strong focus on building and strengthening populations of native species by influencing environmental factors or restocking the population at risk. Once this is achieved then the remaining time, effort and money could be put towards stopping alien species from entering our country or catching them in the very early stages when eradication is straightforward. These measures in addition to filling knowledge gaps by researching the full impact of invasive species could lead to an all round more sustainable system.

What do you think are invasive species here to stay? should we focus more on strengthening our natives?