Climate change and invasive species

Climate change and invasive species refers to the process of the environmental destabilization caused by climate change. This environmental change facilitates the spread of invasive species — species that are not historically found in a certain region, and often bring about a negative impact to that region's native species. This complex relationship is notable because climate change and invasive species are also considered by the USDA to be two of the top four causes of global biodiversity loss.^[2]

The interaction between climate change and invasive species is complex and not easy to assess. Climate change is likely to favour some invasive species and harm others,^[3] but few authors have identified specific consequences of climate change for invasive species.^[4] Consequences of climate change for invasive species are distinct from consequences for native species due to different characteristics (traits and qualities associated with invasions), management and abundance^[4] and can be direct, through the species survival, or indirect, through other factors such as pest or prey species.^[5]

Human-caused climate change and the rise in invasive species are directly linked to changing of ecosystems.^[6][7] The destabilization of climate factors in these ecosystems can lead to the creation of a more hospitable habitat for invasive species, thus allowing them to spread beyond their original geographic boundaries.^[8] Climate change broadens the invasion pathway that enables the spread of species. Not all invasive species benefit from climate change, but most observations show an acceleration of invasive populations. Examples of invasive species that have benefited from climate change include insects (such as the Western corn rootworm and other crop pests), pathogens (such as cinnamon fungus), freshwater and marine species (such as the brook trout), and plants (such as the umbrella tree).

Measurably warmer or colder conditions create opportunities for non-native terrestrial and marine organisms to migrate to new zones and compete with established native species in the same habitat. Given their remarkable adaptability, non-native plants may then invade and take over the ecosystem in which they were introduced.^[9][10][11]

So far, there have been more observations of climate change having a positive or accelerating effect on biological invasions than a negative one. However, most literature focuses on temperature only and due to the complex nature of both climate change and invasive species, outcomes are difficult to predict.

There are many ways to manage the impact of invasive species. Prevention, early detection, climate forecasting and genetic control are some ways communities can mitigate the risks of invasive species and climate change. Although the accuracy of models that study the complex patterns of species populations are difficult to assess, many predict range shifts for species as climates change.