Trends in the detection of aquatic non‐indigenous species across global marine, estuarine and freshwater ecosystems: A 50‐year perspective

Abstract

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.

Biopollution by Invasive Marine Non-Indigenous Species: A Review of Potential Adverse Ecological Effects in a Changing Climate

“…The number of records of aquatic NIS is steadily growing since the last 50 years: first records of detection (1965–2015) across 49 aquatic ecosystems worldwide have been censused [ 45 ]. Patterns of detection rate, richness, and transport pathways revealed an annual mean of 43 (±16 SD) primary detections of NIS.…”

“…Arthropods, molluscs, and fish were the most frequently reported groups. Most NIS were likely introduced as stowaways in ships’ ballast water or as biofouling [ 45 , 46 ].…”

The Role of Vessel Biofouling in the Translocation of Marine Pathogens: Management Considerations and Challenges

“…Typically, any substrate placed in natural waters is quickly colonized by micro-organisms (creating a biofilm, also known as the slime layer) that is followed by a succession of diverse sessile or sedentary micro-and macro-organisms (Flemming, 2002;Aldred and Clare, 2008;Amara et al, 2018). Vessel biofouling is acknowledged as a major, and perhaps the most important, pathway for the introduction, establishment, and subsequent spread of marine non-indigenous macroorganisms (Drake and Lodge, 2007;Hewitt and Campbell, 2010;Bell et al, 2011;Ruiz et al, 2015;Bailey et al, 2020). Similar to the concerns over the transport of human pathogens in ships' ballast water (McCarthy and Khambaty, 1994;Ruiz et al, 2000a;Cohen et al, 2012), the potential for vessel biofouling to act as a vector for non-indigenous pathogens has been highlighted for some time (e.g., Howard, 1994).…”

Economic costs of biological invasions in protected areas worldwide - where do we stand?

“…IAS are also responsible for detrimental impacts on human health and well-being (Conn 2014;Hulme 2014;Mazza and Tricarico 2018;Schaffner et al 2020), and cause losses to multiple sectors of the economy (Pimentel et al 2005;Colautti et al 2006;Martins et al 2006;Xu et al 2006;Kettunen et al 2009;Engeman et al 2010;Hoffmann and Broadhurst 2016;Pratt et al 2017;Diagne et al in press-a). Alarmingly, with no signs of abatement in the numbers of established alien species in recent decades, their associated environmental, social and economic impacts will likely continue to dramatically increase in the foreseeable future (Seebens et al 2017(Seebens et al , 2020Bailey et al 2020). As a result, there is an urgent need for establishing effective management responses.…”