Browsing by Author "Carlton, J. T."

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    Four priority areas to advance invasion science in the face of rapid environmental change
    (Canadian Science Publishing, 2021) Ricciardi, A.; Iacarella, J. C.; Aldridge, D. C.; Blackburn, T. M.; Carlton, J. T.; Catford, J. A.; Dick, J. T. A.; Hulme, P. E.; Jeschke, J. M.; Liebhold, A. M.; Lockwood, J. L.; MacIsaac, H. J.; Meyerson, L. A.; Pysek, P.; Richardson, D. M.; Ruiz, G. M.; Simberloff, D.; Vila, M.; Wardle, D. A.
    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.
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    Trends in the detection of aquatic non-indigenous species across global marine, estuarine and freshwater ecosystems : a 50-year perspective
    (Wiley Online, 2020) Bailey, S. A.; Brown, L.; Campbell, M. L.; Canning-Clode, J.; Carlton, J. T.; Castro, N.; Chainho, P.; Chan, F. T.; Creed, J. C.; Curd, A.; Darling, J.; Fofonoff, P.; Galil, B. S.; Hewitt, C. L.; Inglis, G. J.; Keith, I.; Mandrak, N. E.; Marchini, A.; McKenzie, C. H.; Occhipinti-Ambrogi, A.; Ojaveer, H.; Pires-Teixeira, L. M.; Robinson, T. B.; Ruiz, G. M.; Seaward, K.; Schwindt, E.; Son, M. O.; Therriault, T. W.; Zhan, A.
    Aim The introduction of aquatic non-indigenous species (ANS) has become a major driver for global changes in species biogeography. We examined spatial patterns and temporal trends of ANS detections since 1965 to inform conservation policy and management. Location Global. Methods We assembled an extensive dataset of first records of detection of ANS (1965–2015) across 49 aquatic ecosystems, including the (a) year of first collection, (b) population status and (c) potential pathway(s) of introduction. Data were analysed at global and regional levels to assess patterns of detection rate, richness and transport pathways. Results An annual mean of 43 (±16 SD) primary detections of ANS occurred—one new detection every 8.4 days for 50 years. The global rate of detections was relatively stable during 1965–1995, but increased rapidly after this time, peaking at roughly 66 primary detections per year during 2005–2010 and then declining marginally. Detection rates were variable within and across regions through time. Arthropods, molluscs and fishes were the most frequently reported ANS. Most ANS were likely introduced as stowaways in ships’ ballast water or biofouling, although direct evidence is typically absent. Main conclusions This synthesis highlights the magnitude of recent ANS detections, yet almost certainly represents an underestimate as many ANS go unreported due to limited search effort and diminishing taxonomic expertise. Temporal rates of detection are also confounded by reporting lags, likely contributing to the lower detection rate observed in recent years. There is a critical need to implement standardized, repeated methods across regions and taxa to improve the quality of global-scale comparisons and sustain core measures over longer time-scales. It will be fundamental to fill in knowledge gaps given that invasion data representing broad regions of the world's oceans are not yet readily available and to maintain knowledge pipelines for adaptive management.