So far, fewer invasive species have been recorded at high latitudes but this may stem from the fact that there have been fewer Arctic studies. There is however an increased effort in identifying the new introductions and pathways.
Finding out what is already there
One such study was led by Jesica Goldsmit, PhD candidate, a benthic invertebrate survey to create a baseline for the early detection of non-indigenous species on the Canadian Arctic coastline. The survey was carried out in the three Canadian Arctic ports, Churchill (Manitoba), Deception Bay (Quebec) and Iqaluit (Nunavut), thought to be at the highest risk of exposure to NIS due to their level of shipping activity. A total of 236 genera and species were identified. Of these, 14.4% of the taxa identified are new records within the port regions and 7.2% within the more extended, adjacent surrounding regions.
"These figures are within the expected values considering the size of the region of study" explains Goldsmit, "as the Canadian Arctic is a vast area. Our study is the first step in creating a comprehensive baseline to know what is there so we are able to document any changes. This is such an important step that even new species can be discovered, as has been the case for a new polychaete that has been described and identified for the first time."
As well as new species, seven species found have been categorized as cryptogenic. These may be native or invasive but there is not enough information about their origin. This is due to a lack of historical information, but also as Goldsmit explains, an unclear distribution pattern. Only one of these species, the polychaete Aricidea hartmani, has been found in other regions of the Canadian Arctic. Some of the other species have been found in West Greenland coasts and in some regions of the European and Asian Arctic. "We term these species cryptogenic since we are not certain about their origin, but in the case they could be considered non-native, the most probable explanation for their introduction would be through shipping."
Monitoring challenges
Conditions in the Canadian Arctic mean that it is not easily accessible all year due to winter conditions, and even during summer time, the logistics to access and sample the intertidal and subtidal regions with professional divers is complicated.
"In an ideal world", Goldsmit says, "we would do monitoring surveys every year. The baseline study we carried out is not feasible as an annual monitoring program. If we count the actual area sampled in our survey (80 core samples per port) we ended up sampling only 6 m2. Compare that area to the complete coastline of the Canadian Arctic, which is almost 2 million km2 and we realize how much there is left to know." To increase the established baseline, new techniques and new ways to survey (e.g.; photo analysis and environmental DNA) could contribute, if they are combined with core and quadrat samples such as the kind of study that Goldsmit's team performed. "A collaborative project (DFO, UQAR and Université Laval) recently received funding (through CHARS) to work on developing eDNA techniques and community based training in user-friendly port sampling methods with the goal of having more regular and cost effective monitoring. We will be initiating this program this summer and it is planned to be carried out over the next 3 years in several ports in the Canadian Arctic."
Containment challenges
When talking about the challenges of containing invasive species, Goldsmit lists communication as a key player. "One of the most important things is to transmit the information and the results that we obtain in our studies so that the public become aware of how species can be transported unintentionally and the possible consequences that this could have. Managers and policymakers also need to understand the scale of the problem of invasive species and make policies that prevent new introductions."
