The times are changing: temporal shifts in patterns of fish invasions in central European fresh waters

Abstract

This study examines the invasion history of alien fish species based on exhaustive national data sets on fish invasions of two contiguous central European countries (Germany and Austria). Fifteen alien fish species are currently established in both countries, constituting 14 and 17% of the total freshwater fish fauna of Germany and Austria, respectively. In both countries, six alien species are present, but not established. The status of five alien species in Germany and three species in Austria remains unknown. Accumulation rates of alien fish species have increased in recent decades with >50% of them reported after 1971. North America and Asia were the primary sources of alien fish species in Germany and Austria up to the 1980s, whereas European species of Ponto-Caspian origin dominate now. Fisheries (including aquaculture) and the animal trade were responsible for most earlier introductions, whereas waterways were the main pathway for recent invaders. The extent of the spatial distribution of alien species was positively correlated with residence time, i.e. the time elapsed since the first national record. Different thermal preferences of early invaders (mostly coldwater species) and new invaders (typically warmwater adapted) may benefit the latter in the face of climate change. It is concluded that new challenges for alien fish management arise and that ecosystem-based approaches as endorsed by the E.U. Water Framework Directive (maintaining or restoring good ecological status of rivers and streams) should become the centrepiece of river management in Europe.

Forensic reconstruction ofIctalurus punctatusinvasion routes using on-line fishermen records

“…The main vectors of non-native fish (NNF) introductions are aquaculture, recreational fisheries and ornamental fish trade (Welcomme, 1988;Gozlan et al, 2010), although the importance of these vectors varies geographically. For instance, while aquaculture and waterways are the main reasons for NNF introduction and establishment in central Europe, recreational fisheries are the predominant vector in the Iberian Peninsula (Elvira and Almodóvar, 2001;Ribeiro et al, 2009a;Rabitsch et al, 2013). The Iberian Peninsula has been referenced as a fish invasion hotspot (Leprieur et al, 2008), which is of major concern given its large number of endemic species with restricted distributions (Filipe et al, 2009).…”

Alien Fish Species in France with Emphasis on the Recent Invasion of Gobies

“…The timing and reasons of introductions of alien species in France are, in general terms, similar to other European countries [3,16,34], such as in Belgium [51], Germany/Austria [52,53], Bulgaria [55], Poland [56], or Norway [57]. The first species that was introduced in France is the common carp Cyprinus carpio in roman times, followed by the goldfish Carassius auratus [41,42].…”

Occurrence of non‐native fishes in the Danube east of Vienna (Austria) and potential interactions of invasive gobiids with native fishes

“…Goldfish were the first non‐native fishes in Central Europe. They were released by aquarists, which is also the most likely explanation for their occurrence within the study area (Rabitsch et al, ; Wiesner et al, ). Due to stricter regulations on introductions and warm water discharges into natural water bodies, their populations have declined in recent years (Wiesner et al, ).…”

“… Status indicates if a species is considered as established (E) or not established (N) in Austria (following Wiesner et al, and Rabitsch et al, ). GABLIS is a risk assessment method in which non‐native species are assigned to white, grey (GL), or black lists (BL) according to the severity of their impact (Essl et al, ).…”