Arctic Yearbook 2015 - Page 186

186 Marine pill bug Arctic Yearbook 2015 Sphaeroma walkeri Invertebrate Arthropod Other Beaufort Sea - continental coast and shelf Source: (Molnar et al., 2008) Questions to be answered about these species include the means through which, and the time at which, they arrived at the aforementioned destinations either purposefully or accidentally. More importantly, perhaps, questions include what ecological and economic damages should be expected from these introductions if they spread, and what policy actions can and should be taken to minimize these damages (Burnett et al. 2006; Fernandez & Sheriff 2013; Fernandez 2007, 2008, 2011, 2014; Kaiser 2006). It is worth mentioning that it is a viable hypothesis for all of them to have been transported through hull fouling and ballast water discharge. What is highly likely though, as suggested by Ruiz & Hewitt (2009), is that our limited taxonomic knowledge and respective capacity for biogeographic and taxonomic resolution together with potential biases in search efforts may have resulted in limited observed differences in nonnative species richness and thus in underestimation of nonnative species. Here again, biases in our understanding of Arctic ecosystems limit our ability to answer these questions. While observations of ecosystem behaviors by indigenous Arctic peoples have come to be greatly appreciated for their astuteness and breadth (Krupnik & Jolly 2002; Lopez 1986), such observations focus on direct food sources and/or threats to survival, and cannot be expected to include comprehensive submarine surveillance that might allow specific identification of the details of long run benthic habitat changes, instead of primarily the bio-economic consequences of such changes. The scale of concern for such diverse invasions and their potential consequences is very different but still joint consideration and common prevention strategies focused on disruption of human-induced introduction pathways (such as broad actions, like mitigating climate change impacts, or locally specific requirements, such as ballast water exchange regulations, etc.) offer considerable economies of scope. Fighting against more than one species at a time can be expedient towards developing common policy channels that will enable effectively attacking the invasion threat at once. Conclusions The threats of invasive species’ introductions in the Arctic are increasing as economic and ecological shifts increase opportunities for both introduction of new species and their establishment (Fernandez et al. 2014). In the Arctic Ocean, intentional and unintentional invasions are already underway. The invasions about which we have the greatest evidence are also directly profitable crustacean species. Two of these species, the RKC and the SC, are introductions i