Global thermal niche models of two European grasses show high invasion risks in Antarctica

Abstract

The two non‐native grasses that have established long‐term populations in Antarctica (Poa pratensis and Poa annua) were studied from a global multidimensional thermal niche perspective to address the biological invasion risk to Antarctica. These two species exhibit contrasting introduction histories and reproductive strategies and represent two referential case studies of biological invasion processes. We used a multistep process with a range of species distribution modelling techniques (ecological niche factor analysis, multidimensional envelopes, distance/entropy algorithms) together with a suite of thermoclimatic variables, to characterize the potential ranges of these species. Their native bioclimatic thermal envelopes in Eurasia, together with the different naturalized populations across continents, were compared next. The potential niche of P. pratensis was wider at the cold extremes; however, P. annua life history attributes enable it to be a more successful colonizer. We observe that particularly cold summers are a key aspect of the unique Antarctic environment. In consequence, ruderals such as P. annua can quickly expand under such harsh conditions, whereas the more stress‐tolerant P. pratensis endures and persist through steady growth. Compiled data on human pressure at the Antarctic Peninsula allowed us to provide site‐specific biosecurity risk indicators. We conclude that several areas across the region are vulnerable to invasions from these and other similar species. This can only be visualized in species distribution models (SDMs) when accounting for founder populations that reveal nonanalogous conditions. Results reinforce the need for strict management practices to minimize introductions. Furthermore, our novel set of temperature‐based bioclimatic GIS layers for ice‐free terrestrial Antarctica provide a mechanism for regional and global species distribution models to be built for other potentially invasive species.

Range-wide pattern of genetic variation in Colobanthus quitensis

“…There are a lot of species which have ecophysiological features required for survival in the polar environment including those from the Colobanthus genus like e.g., C. lycopodioides, C. subulatus and, C. lechleri, that partly cover C. quitensis range and tolerate similar edaphic conditions. That support partly fact that only records of successful introduction and establishment of species in Maritime Antarctic form lower latitudes (e.g., Chwedorzewska et al 2015;Pertierra et al 2017a) are via human vectors (Lityńska-Zając et al 2012).…”

What are the best predictors for invasive potential of weeds? Transferability evaluations of model predictions based on diverse environmental data sets for Flaveria bidentis

“…We also used the hierarchical method in BRT to rank importance of variables. Both the ENFA and BRT methods have been explored in previous studies (ENFA: Aragon et al ., 2010; Pertierra et al ., ; BRT: Roura‐Pascual et al ., ; Petitpierre et al ., ). Finally, a recently proposed algorithm based on fluctuation index (FI) was explored.…”

“…Roura‐Pascual et al ., ; Petitpierre et al ., ) and ecological niche factor analysis (ENFA; e.g. Aragón et al ., ; Pertierra et al ., ). Finally, a newly released algorithm based on fluctuation index (FI, Guisande et al ., ) offers an additional alternative.…”

Surviving the Antarctic Winter—Life Stage Cold Tolerance and Ice Entrapment Survival in The Invasive Chironomid Midge Eretmoptera murphyi

“…Variation in the levels of cold tolerance between different larval instars have also been found in moths, e.g., Epiphyas postvittana [36] and Spilonota ocellana [37], as well as in mites [29]. As the predicted warming of the polar regions gains pace [38], more species are expected to be able to colonize higher latitude environments [39], and predicting which species are able to cope with the challenging environment is essential to understanding their invasion ecology e.g., [40,41]. A successful species in the polar regions must be able to develop, feed and reproduce in the short available growth seasons [42,43], as well as be able to overwinter successfully [13,44,45].…”