Search

Abstract: Incorporating physiology into models of population dynamics will improve our understanding of how and why invasions succeed and cause ecological impacts, whereas others fail or remain innocuous. Targeting both organismal physiologists and invasion scientists, we detail how physiological processes affect every invasion stage, for both plants and animals, and how physiological data can be better used for studying the spatial dynamics and ecological effects of invasive species. We suggest six steps to quantify the physiological functions related to demography of nonnative species: justifying physiological traits of interest, determining ecologically appropriate time frames, identifying relevant abiotic variables, designing experimental treatments that capture covariation between abiotic variables, measuring physiological responses to these abiotic variables, and fitting statistical models to the data. We also provide brief guidance on approaches to modeling invasions. Finally, we emphasize the benefits of integrating research between communities of physiologists and invasion scientists.

Unprecedented rates of introduction and spread of non-native species pose burgeoning challenges to biodiversity, natural resource management, regional economies, and human health. Current biosecurity efforts are failing to keep pace with globalization, revealing critical gaps in our understanding and response to invasions. Here, we identify four priority areas to advance invasion science in the face of rapid global environmental change. First, invasion science should strive to develop a more comprehensive framework for predicting how the behavior, abundance, and interspecific interactions of non-native species vary in relation to conditions in receiving environments and how these factors govern the ecological impacts of invasion. A second priority is to understand the potential synergistic effects of multiple co-occurring stressors-particularly involving climate change--on the establishment and impact of non-native species. Climate adaptation and mitigation strategies will need to consider the possible consequences of promoting non-native species, and appropriate management responses to non-native species will need to be developed. The third priority is to address the taxonomic impediment. The ability to detect and evaluate invasion risks is compromised by a growing deficit in taxonomic expertise, which cannot be adequately compensated by new molecular technologies alone. Management of biosecurity risks will become increasingly challenging unless academia, industry, and governments train and employ new personnel in taxonomy and systematics. Fourth, we recommend that internationally cooperative biosecurity strategies consider the bridgehead effects of global dispersal networks, in which organisms tend to invade new regions from locations where they have already established. Cooperation among countries to eradicate or control species established in bridgehead regions should yield greater benefit than independent attempts by individual countries to exclude these species from arriving and establishing. Key words: biosecurity, climate change, ecological impact, invasive species, management, risk assessment. Les taux sans precedent d'introduction et de propagation d'especes non indigenes posent des defis croissants a la biodiversite, a la gestion des ressources naturelles, aux economies regionales et a la sante humaine. Les efforts actuels en matiere de biosecurite ne parviennent pas a suivre le rythme de la mondialisation, revelant des lacunes critiques dans notre comprehension et notre reponse face aux invasions. Les auteurs identifient ici quatre domaines prioritaires permettant de faire progresser la science des invasions face aux changements environnementaux mondiaux rapides. Premierement, la science des invasions devrait s'efforcer de developper un cadre plus complet pour predire comment le comportement, l'abondance et les interactions interspecifiques des especes non indigenes varient en fonction des conditions des environnements recepteurs et comment ces facteurs regissent les impacts ecologiques des invasions. Une deuxieme priorite consiste a comprendre les effets synergiques potentiels de multiples facteurs de stress concomitants--notamment les changements climatiques--sur l'etablissement et l'impact des especes non indigenes. Les strategies d'adaptation au climat et d'attenuation devront tenir compte des consequences possibles de la promotion des especes non indigenes, et des reponses de gestion appropriees aux especes non indigenes devront etre elaborees. La troisieme priorite est de s'attaquer a l'obstacle taxonomique. La capacite a detecter et a evaluer les risques d'invasion est compromise par un deficit croissant de competences taxonomiques, qui ne peut etre compense de maniere adequate par les nouvelles technologies moleculaires seules. La gestion des risques de biosecurite deviendra de plus en plus difficile a moins que les universites, l'industrie et les gouvernements forment et emploient du nouveau personnel dans les domaines de la taxonomie et de la systematique. Quatriemement, nous recommandons que les strategies de cooperation internationale en matiere de biosecurite tiennent compte des effets de tete de pont des reseaux de dispersion mondiaux, dans lesquels des organismes ont tendance a envahir de nouvelles regions a partir d'endroits ou ils sont deja etablis. La cooperation entre les pays pour eradiquer ou controler les especes etablies dans les regions de tete de pont devrait donner de meilleurs resultats que les tentatives independantes de chaque pays pour empecher ces especes d'arriver et de s'etablir. [Traduit par la Redaction] Mots-cles: biosecurite, changements climatiques, impact ecologique, especes envahissantes, gestion, evaluation des risques., 1. Introduction Invasion science--the systematic investigation of the causes and consequences of biological invasions--is a rapidly evolving interdisciplinary field. Its explosive growth over the past few decades mirrors societal concern [...]

SummaryVan der Wal et al. (2015) (henceforth VdW) attempted to evaluate the degree to which the geographical origin of a species shapes people's attitudes towards conservation management decisions. Based on questionnaire surveys of the general public and experts from Scotland and Canada, the authors perceive “widespread use of the label ‘non-native’ as a proxy for harmfulness” and a species' origin as being used as shorthand for “harmfulness” (pp. 349 & 352). However, the authors cited by VdW do not take such a categorical view. Invasions of non-native species are also often just symptoms, not causes of human-created environmental changes. VdW focus on well-known species with long introduction histories for which the potential abundance and impact can plausibly be judged by experts and the public alike. However, when a decision is to be made regarding whether a non-native taxon that is not yet present in the local biota should be introduced, or whether a recently established and geographically restricted but spreading non-native taxon should be controlled, the taxon's origin should be a primary component in the decision-making process.