Climate change as a factor enhancing the invasiveness of alien species

Climate is one of the key factors governing the biological invasions of alien species, thus its change may have significant consequences for the scale of this process. We analyzed the predicted influence of climate change on the invasiveness of alien species in Poland and identified species susceptible to climate change. A total of 60 species of alien plants and 58 animals were assessed through an expert elicitation process. For 79 species climate change was assessed as the factor enhancing the likelihood of introduction, establishment, spread and/or impact in the future. Currently, the majority of these species are not widespread in Poland, and this list includes species totally absent, or present only in cultivation and captivity. Climate change will increase the number of high-risk invasive alien species (IAS) from 38 to 63. Species originating in warmer parts of the world are most susceptible to climate change. The majority of the high-risk IAS are regulated under the EU and Polish legislature. However, no restrictions have been imposed on some of the high-risk IAS. Since climate change will further increase their invasiveness, implementation of legal provisions towards these species is recommended.