Diet and feeding ecology of the pike perch (Sander lucioperca), an invasive fish species: seasonal diet shifts

Abstract

Sander lucioperca represents a potential candidate for aquaculture in Moroccan freshwater, but information concerning its diet and feeding habits is still lacking. This study therefore aims to contribute to the knowledge of the feeding ecology of this invasive species in Al Massira Reservoir, with particular emphasis on seasonal and intraspecific diet variation. Analysis of stomach contents revealed that the pike perch diet consists of various prey items, with an abundance of Lepomis gibbosus. However, S. lucioperca is also an opportunistic predator, capable of consuming other food resources when they become available in its habitat. This opportunistic behavior may account for the successful establishment of this species' population in a large reservoir, despite the coexistence of other carnivorous fish species. The dietary composition indicated a carnivorous diet with considerable seasonal variation. There was no significant sex-related or ontogenetic variation in the diet. The feeding intensity is similar between males and females, as well as across different size classes, but it varies according to the seasons. The results provide fundamental information about the feeding habits of this species, which is used for artificial culture research.