“…Ide, is a rheophileous cyprinid, widely distributed in Europe, especially in rivers and lakes (Jamróz et al, 2008;Cejko et al, 2010;Ciesla et al, 2014). In recent years, reproduction of Ide in captivity has received increasing attention to meet the demand of high quality juveniles for restocking (Wojda, 2004;Krejszeff et al, 2009), sport fishing, aquarium industry (Jamróz et al, 2008;Cejko et al, 2010), toxicity studies (Witeska et al, 2014) and as a bio-monitoring agent (Fenske et al, 2006). On the other hand, Northern pike is an iteroparous, large-bodied and long-living (>10 years) fish species inhabiting the northern hemisphere (Craig, 2008;Forsman et al, 2015).…”