A global analysis of the determinants of alien geographical range size in birds

Abstract

Aim Determining the causes of range size variation in the distributions of alien species is important for understanding the spread of invasive species. Factors influencing alien range size have been explored for some species at a regional level, but to date there has been no global analysis of an entire class. Here, we present such an analysis for birds, testing for the effects of introduction event, location and species-level variables on alien range sizes. Location Global. Methods We used a novel dataset on the global distributions of alien bird species to test for relationships between alien range size and colonization pressure, residence time, extent of the global climatic niche, native range size, body mass and specialization, using a statistical approach based on phylogenetic generalized least squares models. We performed this analysis globally, and for separate biogeographical realms. Results Approximately half of the variation in alien bird range size is explained by colonization pressure in univariate analysis. We identified consistent effects of higher colonization pressure at global and realm levels, as well as support for effects of native range size and residence time. We found less support for effects of body mass, specialization or extent of the global climatic niche on alien range size. Main conclusions Alien bird range sizes are generally small relative to their native range sizes, and many are continuing to expand. Nevertheless, current variation is predictable, most strongly by the event-level factor of colonization pressure. Whether a species is widespread is a better predictor of alien range size than whether a species could be widespread (estimated by global climatic niche extent), while we also find effects of residence time on alien range size. These relationships may help to identify those alien species that are more likely to spread and hence have greater environmental and economic impacts where they have been introduced. KeywordsAlien, avian ecology, bird, body mass, geographical range size, global climatic niche extent, number of introductions, residence time, specialisation.2009), but there remain significant gaps in our understanding. Most notably, apart from a few case studies (e.g. Liversidge, 1962;Silva et al., 2002), the processes determining the geographical spread of alien bird species, and their resulting geographical range sizes, have largely been ignored (Mack et al., 2000;Blackburn et al., 2009). Geographical range size

Biotic resistance or introduction bias? Immigrant plant performance decreases with residence times over millennia

“…Still, we find that all covariates have important effects on range size. Our results support the well‐known finding that global range sizes and broad habitat or climatic tolerances contribute to invasion success (Cadotte, Murray, & Lovett‐Doust, ; Dyer et al, ; Hayes & Barry, ; Pyšek et al, ). Climatic differences between Germany and a species’ global range also had a negative effect on range sizes, indicating that pre‐adaptation to climatic conditions may be an important determinant of invasion success (Hayes & Barry, ; Petitpierre et al, ).…”

Integrating transport pressure data and species distribution models to estimate invasion risk for alien stowaways

“…Our case study of D. melanosticus in Australia provides a proof of concept of the utility of our approach to inform quarantine and surveillance efforts aimed at managing the risk of arrival and establishment of alien species via the stowaway pathway (Jarrad et al , Yemshanov et al , McGeoch et al 2016). Given the increasing availability of data on historical introductions globally (Kraus , Essl et al , Chapple et al , Dyer et al ), this approach is readily generalizable to a wide array of countries and taxonomic groups.…”

Biological traits, phylogeny and human footprint signatures on the geographical range size of passerines (OrderPasseriformes) worldwide

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