Protected areas (PAs) are defended as refugia for some of the world’s most threatened organisms, but little is known about their potential to resist the damaging effects of biological invasions.

This study investigates the current and future potential distributions of 100 of the most invasive terrestrial, freshwater, and marine species in Europe. This information is used to evaluate the combined threat posed by climate change and invasions to existing PAs and the most susceptible species they shelter.

The authors found that only one quarter of Europe´s marine and terrestrial areas protected over the last 100 years have been colonized by any of the invaders investigated, despite offering climatically suitable conditions for invasion. In general terms, it is shown that invasive species are rare in long-established national parks and nature reserves, which are actively protected and often located in remote and pristine regions with very low human density. In contrast, the study found that the richness of invasive species is high in the more recently designated Natura 2000 sites, which are subject to high human accessibility.

In relation to invasive species under climate change in PAs, the authors conclude that PAs have the potential to provide strategic refugia to native species from the expansion of invasive species spreading under climate change. And underline that understanding the mechanisms underlaying such potential is crucial in facilitating the identification of areas of future conservation concern as well as opportunities for restoration.

Gallardo B, Aldridge DC, González-Moreno P, Pergi J, Pizarro M, Pyšek P, Thuiller W, Yesson C, Vilà M (2017) Protected areas offer refuge from invasive species spreading under climate change. Global Change Biolology 23:5331-5343