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Cover -- Title Page -- Copyright -- Contents -- Preface | Gary Paul Nabhan -- Acknowledgments -- Introduction | Barbara Tellman -- Part One. The Broad Perspective: The Introduction and Spread of New Species -- 1. Deep History of Immigration in the Sonoran Desert Region | Thomas R. Van Devender -- 2. Human Introduction of Exotic Species in the Sonoran Region | Barbara Tellman -- 3. Exotic Plant Species in the Western United States: Putting the Sonoran Floristic Province into Perspective Teven P. McLaughlin -- 4. Natural Barriers to Plant Naturalizations and Invasions in the Sonoran Desert | Richard N. Mack -- Part Two. Exotics in Various Areas of the Sonoran Region: Subregions of the Sonoran Region -- 5. Invasive Exotic Plants in the Sonoran Desert | Michael F. Wilson, Linda Leigh, and Richard S. Felger -- 6. Invasive Plants: Their Occurrence and Possible Impact on the Central Gulf Coast of Sonora and the Midriff Islands in the Sea of Cortés Patricia West annd Gary Paul Nabhan -- 7. Invasive Vertebrates on Islands of the Sea of Cortés | Eric Mellink -- 8. Mexican Grasslands, Thornscrub, and the Transformation of the Sonoran Desert by Invasive Exotic Buffelgrass (Pennisetum ciliare) | Alberto Burquez-Montijo, Mark E. Miller, and Angelina Martinez-Yrizar -- 9. Exotic Species in Grasslands | Jane H. Bock and Carl E. Bock -- 10. Alien Annual Grasses and Their Relationships to Fire and Biotic Change in Sonoran Desertscrub | Todd C. Esque and Cecil R. Schwalbe -- 11. Foreign Visitors in Riparian Corridors of the American Southwest: Is Xenophytophobia Justified? | Juliet C. Stromberg and Matt K. Chew -- 12. Widespread Effects of Introduced Species on Reptiles and Amphibians in the Sonoran Desert Region | Philip C. Rosen and Cecil R. Schwalbe.

The Tampa Tribune recently expressed its "shame and outrage" that State politicians were ignoring what the paper calls "perhaps the greatest threat to the State's natural heritage": the invasion of exotic species. These nefarious species were, according to the paper, quite literally "gobbling up Florida's landscape." Here, the terms used to portray this invasion are significant. The Australian melaleuca tree (Melalueca quinquenervia), for example, originally was imported as a means to reclaim land from the soggy marshes of south Florida.

[Aim] Temperature is fundamental to the physiological and ecological performance of marine organisms, but its role in modulating the magnitude of ecological impacts by exotic species remains unresolved. Here, we examine the relationship between thermal regimes in the range of origin of marine exotic species and sites of measured impact, after human-induced introduction. We compare this relationship with the magnitude of impact exerted by exotic species on native ecosystems. ; [Location] Global. ; [Time period] 1977–2017 (meta-analysis). ; [Major taxa studied] Marine exotic species. ; [Methods] Quantitative impacts of exotic species in marine ecosystems were obtained from a global database. The native range of origin of exotic species was used to estimate the realized thermal niche for each species and compared with the latitude and climatic conditions in recipient sites of recorded impact of exotic species. The difference in median temperatures between recipient sites and the thermal range of origin (i.e., thermal midpoint anomaly) was compared with the magnitude of effect sizes by exotic species on native species, communities and ecosystems. ; [Results] Recorded impacts occurred predominantly within the thermal niche of origin of exotic species, albeit with a tendency toward higher latitudes and slightly cooler conditions. The severity of impacts by exotic species on abundance of native taxa displayed a hump-shaped relationship with temperature. Peak impacts were recorded in recipient sites that were 2.2°C cooler than the thermal midpoint of the range of origin of exotic species, and impacts decreased in magnitude toward higher and lower thermal anomalies. ; [Main conclusions] Our findings highlight how temperature and climatic context influence ecological impacts by exotic species in marine ecosystems and the implications for existing and novel species interactions under climate change. ; European Union's Horizon 2020 research and innovation programme, Grant/Award Number: 659246; Australian Research Council, Grant/Award Number: DE200100900 and CE140100020; Spanish Ministry of Economy, Industry and Competitiveness, Grant/Award Number: CGL2015-71809-P; Fundación BBVA; Independent Research Fund Denmark, Grant/Award Number: 8021-00222B. ; Peer reviewed

Plantations offer a high potential to respond to the increasing pressure on forests to deliver social, economic, and environmental services. Exotic tree species have a long history of use in plantation forestry, mostly because of their improved productivity compared with that of native species. Because of their impacts on land management and the environment, questions arise regarding the compatibility of exotic tree plantations with sustainable forest management (SFM), the overarching paradigm driving forest legislations in Canada. Our objectives were thus to i) briefly review the historical and current use of exotic tree species in Canada, ii) identify the social, economic and environmental issues related to the use of exotic tree species in Canadian forestry, based on sustainable forest management criteria, and iii) identify perspectives related to the use of exotic tree species in the sustainable management of Canadian forests. Results show that six out of ten Canadian provinces do not have specific legislations to control the use of exotic tree species for reforestation within their borders. The use of exotic tree species is mainly controlled through third-party certification agencies. Exotic tree species represent a small proportion of the planted seedlings in Canada and Norway spruce is the most common one. The use of exotic tree species is compatible with sustainable forest management criteria used in Canada, but forest managers must take into account several issues related to their use and maintain a social license to be entitled to plant them. Issues are highly dependent upon scale. The zoning of management intensity could provide environmental, economic and social benefits, but costs/benefits analyses should be carried out. The concept of naturalness could also be useful to integrate plantations of exotic species in jurisdiction where SFM strategies are based on ecosystem management principles. Monitoring of hybridization and invasiveness of exotic species must be included in landscape analyses to forestall loss of resilience leading to compromised structural and functional ecosystem states. The use of exotics species is recognized as a tool to sequester carbon and facilitate adaptation of forests to global changes, but it is necessary to carefully identified contexts where assisted migration is justified and disentangle planned novel ecosystems coherent with global changes generated by assisted migration from those emerging from invasive species forming undesired states.

It has been previously suggested that the characteristics that are driving the taxonomic homogenisation of the global avifauna, through the extinction of native bird species and the establishment of exotic bird species, are opposite sides of the same coin. One of the most important tools that conservation biologists and wildlife managers have to ameliorate the extinction of a species is to reintroduce populations to stronghold areas from which they have been extirpated or were not previously common. In this paper, we address the question of what the study of exotic bird introductions can tell us to inform the translocation of native species. We review the relative importance of the five factors that have been suggested significantly to influence the successful establishment of non-native species: introduction effort, environmental matching, species' interactions, species' life histories, and phylogenetic relatedness. Current evidence suggests that introduction effort will be an important determinant of release, but how many individuals need to be released, and in how many separate release events, is contingent on characteristics of species and environment. The importance of climate matching for introduction success suggests that the success of translocations will depend greatly on the study and amelioration of the problem that caused the initial population decline. This is most problematic in situations where the decline is associated with human-induced climate change. Migratory and sexually selected species may be harder to re-establish, but related species may differ substantially in their likelihood of success. We suggest that further insights into the reintroduction process may be gained particularly by studying species that are experiencing a threat in their native range but which are also being widely released as exotics outside of this range.