First Application of FISK, the Freshwater Fish Invasiveness Screening Kit, in Northern Europe: Example of Southern Finland

Abstract

The climatic conditions of north temperate countries pose unique influences on the rates of invasion and the potential adverse impacts of non-native species. Methods are needed to evaluate these risks, beginning with the pre-screening of non-native species for potential invasives. Recent improvements to the Fish Invasiveness Scoring Kit (FISK) have provided a means (i.e., FISK v2) of identifying potentially invasive non-native freshwater fishes in virtually all climate zones. In this study, FISK is applied for the first time in a north temperate country, southern Finland, and calibrated to determine the appropriate threshold score for fish species that are likely to pose a high risk of being invasive in this risk assessment area. The threshold between "medium" and "high" risk was determined to be 22.5, which is slightly higher than the original threshold for the United Kingdom (i.e., 19) and that determined for a FISK application in southern Japan (19.8). This underlines the need to calibrate such decision-support tools for the different areas where they are employed. The results are evaluated in the context of current management strategies in Finland regarding non-native fishes.

Risk screening of non‐native freshwater fishes in Croatia and Slovenia using the Fish Invasiveness Screening Kit

“…) – the exception here is Finland, where the colder climate relative to the UK and southern Europe may limit the species’ invasiveness (Puntila et al . ). A high FISK score also was achieved for the Amur sleeper Perccottus glenii , which is regarded as one of the most invasive fish species in Eastern and Central Europe (Grabowska et al .…”

“…), and the low score recorded in the present study suggests low establishment potential in new areas (Puntila et al . ; but see Onikura et al . ).…”

Comparison of Taxon‐Specific and Taxon‐Generic Risk Screening Tools to Identify Potentially Invasive Non‐native Fishes in the River Neretva Catchment (Bosnia and Herzegovina and Croatia)

“…On the contrary, the high threshold score of 20.25 reported for the Iberian Peninsula has been attributed to a particularly low proportion of translocated species (18.0% or 16 out of 89: Almeida et al , ), which is also consistent with findings for Turkey (14.29% or 5 out of 35: Tarkan et al , ). The present results contrast FISK calibrations from outside the Mediterranean Region, that is, southern Finland (22.5: Puntila et al , ), England and Wales (18.9: Copp et al , ), and southern Japan (19.8: Onikura et al , ), whereas the similarly low threshold score from Florida of 10.25 was not due to translocations but rather because many of the established, high‐risk fishes in that region are not widely introduced, established or invasive on a broader geographical scale (Lawson et al ., ).…”

The invasive bighead goby Ponticola kessleri displays large‐scale genetic similarities and small‐scale genetic differentiation in relation to shipping patterns

“…They are expected to colonize the majority of freshwater and brackish temperate water bodies worldwide (Puntila et al . ; Snyder et al . ; Hempel & Thiel ).…”