Taking control of Invasive Alien Species!

Invasive Alien Species are becoming increasingly widespread and common across the world,  and it is thought that soon, they may take over habitat loss as being the number one cause of ecological destruction. But fear not, scientists and governments are working together to find ways to prevent and eradicate invasions!

Clout & Veitch define two main priorities when trying to minimise further damage to the environment and biodiversity. You can either reduce the risk of new invasions or eradicate the existing invasive populations, both of which are extremely difficult tasks. By either preventing or eradicating Invasive Alien Species (IAS), it can help to increase biodiversity but can also provide economic benefits by removing the causes of agricultural losses for instance. However, the complex dynamic of ecosystems and their species within, make it very hard to successfully do so. 

So how can we successfully eradicate IAS?

There are multiple actions that can be taken to increase the chance of successfully removing an invasive species, as suggested by Pluess et al. For instance, by starting a removal campaign before the infestation gets uncontrollably large or starting to eradicate within the first four years of invasion and by putting focus on IAS that arrive via cultivation. Also, once the removal has begun, ensuring it goes to completion, that species are removed above the rate of reproduction, and the entire population is being accounted for will help to promote success, as explained by Clout & Veitch. 

Invasive Alien Species associated with agriculture are more likely to be eradicated because of economic losses associated when invasions take over, like with the Banana Bunchy Top Virus explored in last weeks post. Also, invasions on islands are more likely to be successfully removed due to the smaller infestation area that is easier to manage. 

EU Regulations

All eradication plans require a lot of cooperation between local people and governments. For instance, on January 1st, 2015, the European Union made a new regulation requiring a list of concerning IAS to be created, prevention methods to be put in place and management schemes set up to quickly eradicate widely spread IAS. It is these large scale plans that improve eradication success by providing larger investments and overall increased efforts although this isn't always enough! 

Issues with Invasive Alien Species eradication!

Despite teams of scientists working to create schemes for eradicating Invasive Alien Species, when they are carried out, it usually doesn't go according to plan.  The outcome of an eradication scheme depends on very special features of both the invading species, the environment surrounding it and fellow inhabiting species. 

 Clout & Veitch explore some of these issues, for instance, eradication success depends on the how the IAS disperses. In plants, for example, if they are spread by wind or birds then their seeds could distribute across a very wide, varying landscape and it is hard to prevent this from happening and fully eradicate certain species.  

Similarly, it is very hard to design eradication techniques that do not harm non-targeted species. On Kapiti Island, brushtail possums (shown to the right) were successfully eradicated, but in the process, 181 birds were also killed in the same traps. This can cause a lot of controversy as members of the public and some organisations, question the ethics of killing a native species in the eradication process of an invasive one. 

However, there is also opposition when it comes to killing the Invasive Alien Species itself.  For instance, the culling of the ruddy duck in England sparked a lot of debate in terms of ethics, as noted by Blackburn et al. Negative responses such as this can jeopardise the progress of eradication schemes and therefore this social aspect also needs to be considered during the planning stage. 

At the end of the day, eradication schemes do involve killing or removing invasive animals, plants or micro-organisms and this is sometimes quite hard to accept. Before exploring Invasive Alien Species throughout this blog, I would have instantly assumed that the eradication of an innocent organism was immoral and avoidable. However, after discovering the major impacts that IAS can have on habitats and their animals within, I've learned that control and elimination can be the lesser of two evils and result in fewer deaths overall. In spite of this, there are steps that we can take to prevent invasions from occurring to prevent lives avoidably being lost. With increasing global transportation and a changing climate, it is our responsibility to reduce the chance of future extinctions and take responsibility for the effects we have.

Do you think its okay to kill entire populations of plants, animals and microorganisms when they may have invaded an area due to humans?

Check out this blog related to marine conservation to see why it is important to prevent more native species loss http://the-turtle-and-the-hare.blogspot.co.uk!