Ruffe From the Former USSR: Variability Within the Largest Part of its Natural Range

The population biology and life history traits of Eurasian ruffe [Gymnocephalus cernuus (L.), Pisces: Percidae] introduced into eutrophic and oligotrophic lakes in Northern Italy

“…Overall, our findings indicate that the ruffe population in l. Mergozzo apparently is still undergoing a boom-and-bust development, as often detected in the early phases of fish invasions (Salonen et al, 2007;Volta and Jepsen, 2008;Liso et al, 2011), while the population in l. Ghirla, established more than 15 years ago, is more balanced and stable. Similar patterns in ruffe population dynamics have been recorded in other lakes, for instance in a new reservoir in Russia (Popova et al, 1998), in Loch Lomond (UK) (Devine et al, 2000) and Llyn Tegid (UK) (Winfield et al, 2011).…”

“…It is able to adapt to many types of water bodies and tolerates marked variations in salinity (Lind, 1977) and productivity (Persson et al, 1991;Mehner et al, 2005) as well as different habitats (Kålås, 1995;Ogle, 1998) and depths (Sandlund et al, 1985). Ruffe is typically invertivorous (Balon et al, 1977), feeding preferentially on benthic organisms, but also occasionally consuming zooplankton (Hölker and Thiel, 1998;Popova et al, 1998). Fish eggs (Adams and Tippett, 1991;Kangur and Kangur, 1996;Rösch and Schmid, 1996;Winfield et al, 2004b) and small fishes (Hölker and Thiel, 1998; and references therein) have also been recorded in the diet of lacustrine populations, making ruffe a potentially significant predator on fish species such as coregonids (Rösch and Schmid, 1996;Winfield et al, 1996).…”

“…Fish eggs (Adams and Tippett, 1991;Kangur and Kangur, 1996;Rösch and Schmid, 1996;Winfield et al, 2004b) and small fishes (Hölker and Thiel, 1998; and references therein) have also been recorded in the diet of lacustrine populations, making ruffe a potentially significant predator on fish species such as coregonids (Rösch and Schmid, 1996;Winfield et al, 1996). Fecundity is high and reproduction can start from an age as young as one or two years, with males maturing earlier than females (Berg, 1965;Popova et al, 1998;Devine et al, 2000;Lorenzoni et al, 2009). The species is of negligible economic value and is generally unattractive for recreational fishing, although its use as live bait by anglers fishing for pike [Esox lucius (L.)] has frequently been linked to its recent dispersal (Winfield and Durie, 2004).…”

“…A potential negative impact of ruffe on perch [Perca fluviatilis (L.)] has been recorded in laboratory experiments (Bergman, 1987;Savino and Kolar, 1996) and some but not all field studies (Bergman, 1991;Bergman and Greenberg, 1994;Winfield et al, 2004a). Management and control of invasive ruffe populations have been attempted by stocking predators (Mayo et al, 1998), using piscicides (Dawson et al, 1998), or by selective removal (Popova et al, 1998;Czypinski and Ogle, 2011 however, been ambiguous (Pihu and Maemets, 1982;Dawson et al, 1998;Mayo et al, 1998;Popova et al, 1998;Czypinski and Ogle, 2011). Although the biology and ecology of ruffe have been extensively described for the temperate-cold regions of its native parts of Europe and the parts of North America where it has been introduced (Gunderson et al, 1998, and references therein), knowledge of its population biology and life history in more southerly Mediterranean areas is scarce and limited to the basin of the Tevere river near Rome, Italy (Carosi et al, 1998;Lorenzoni et al, 2007).…”

Ecological and behavioural influences on juvenile fish migrations in regulated rivers: a review of experimental and field studies

“…Besides its low energy demands, ruffe is very flexible in terms of foraging behaviour (Popova et al, 1998). It can easily switch from the pelagic to benthic feeding mode, or combine both.…”