Invasive Alien Species are specific types of plants, animals and micro-organisms that are not native to an ecosystem and when introduced into it they can present a serious threat to the native biodiversity or cause economic damage (e.g. in agriculture, fish farming, infrastructure) or have adverse effects on human health through disease transmission.
Invasive alien species compete with indigenous species for resources (food, water and light) and living spaces and usually displace them or alter their role in the biocommunities. They can also lead indigenous species to extinction through predation, parasitism, disease transmission, grazing, toxic effects or destruction of their habitats or even through hybridization with them. In many cases, these species are not invasive in their natural habitat, likely due to the existence of their natural enemies that keep their populations under control. Their frequency of occurrence in new areas and the dangers they pose are constantly increasing due to the international trade, transport, tourism and climate change. Invasive alien species are considered to be globally the second greatest threat to biodiversity after Habitat degradation and fragmentation.
In the European Union environment, approximately 12,000 species are alien, of which 10-15% are estimated to be invasive. It has been estimated that at least €12 billion a year is spent to control these species and the damage they cause in Europe. Recognizing the seriousness of the problem, the European Union adopted Regulation 1143/2014 on the prevention and management of the introduction and spread of invasive alien species. This Regulation entered into force on 1 January 2015 and lays down rules for the prevention, minimization and mitigation of adverse effects from the introduction and spread, whether voluntary or involuntary, of invasive alien species on biodiversity in the E.U.
Through the Regulation an initial list of 37 invasive alien species of Union concern has been issued, based on specific criteria and risk assessment, which will be revised and updated by adding new species with negative impacts on biodiversity in the European Union. The species on the EU list are subject to prohibitions, restrictions and regulations aimed at the prevention, early detection, treatment and management of invasive alien species in the EU.
Serious measures must therefore be taken to control the import and establishment of these species and to deal with those who have already entered. All this of course involves informing the public about the dangers posed by illegal imports, possession and release of exotic species to the local environment and the creation of a database containing information of the types and geographical distribution and dispersion, as well as periodic inspections of premises in which alien species are likely found, such as nurseries, florists, aquariums, fish-farming units, laboratories, zoos and more.
Useful Links: http://ec.europa.eu/environment/nature/invasivealien/index_en.htm