Socioeconomic legacy yields an invasion debt

Abstract

Globalization and economic growth are widely recognized as important drivers of biological invasions. Consequently, there is an increasing need for governments to address the role of international trade in their strategies to prevent species introductions. However, many of the most problematic alien species are not recent arrivals but were introduced several decades ago. Hence, current patterns of alien-species richness may better reflect historical rather than contemporary human activities, a phenomenon which might be called "invasion debt." Here, we show that across 10 taxonomic groups (vascular plants, bryophytes, fungi, birds, mammals, reptiles, amphibians, fish, terrestrial insects, and aquatic invertebrates) in 28 European countries, current numbers of alien species established in the wild are indeed more closely related to indicators of socioeconomic activity from the year 1900 than to those from 2000, although the majority of species introductions occurred during the second half of the 20th century. The strength of the historical signal varies among taxonomic groups, with those possessing good capabilities for dispersal (birds, insects) more strongly associated with recent socioeconomic drivers. Nevertheless, our results suggest a considerable historical legacy for the majority of the taxa analyzed. The consequences of the current high levels of socioeconomic activity on the extent of biological invasions will thus probably not be completely realized until several decades into the future.exotic plants and animals | species establishment | time lag

Conceptual Frameworks and Methods for Advancing Invasion Ecology

“…An increasing number of studies already advance in that direction, e.g., by analyzing historic catalogues (Dehnen-Schmutz et al 2007;Blackburn et al 2010), by explaining patterns in alien species richness based on indicators of current and historic socio-economic conditions (Hulme 2009;Essl et al 2010), or by considering factors like economic value of species and invasions (Born et al 2005;Gozlan et al 2010). Another way to bridge the gap between ecology and social sciences is to combine vector science (Carlton and Ruiz 2005) with the study of continually shifting global decentralized networks (Barabási 2002).…”

Impacts of biological invasions: what's what and the way forward

“…Furthermore, molecular methods increasingly reveal that what had been regarded as 'invasion' might instead result from new genotypes from distant sources [29]. Concern is also heightened because many introduced populations remain innocuous for extended periods before spreading and becoming invasive [30,31]. For instance, Brazilian pepper remained restricted in Florida for a century before rapidly expanding across a wide area [30], whereas plants introduced to Europe might take 150-400 years to reach their fullest areal extent [32].…”

Using Available Information to Assess the Potential Effects of Climate Change on Vegetation in the High Arctic: North Billjefjorden, Central Spitsbergen (Svalbard)

“…The main potential for invasion probably lies with past arrivals because those introduced species are already surviving in the region, and climate change could help them spread (Hellmann et al 2008;Essl et al 2011).…”