Seasonal abundance and feeding patterns of the invasive racer goby (Babka gymnotrachelus) in the littoral zone of a lowland European river

Abstract

in catches at the end of May. Almost all juveniles reached adult size in October of the same year. Overall, 72 prey organisms were identified in the gut contents of racer goby. The most abundant prey were chironomids followed by cladocerans, copepods, and water mites. Chironomids included 25 taxa, the most abundant of which were Polypedilum convictum, Glyptotendipes sp., and Chironomus sp. Among 18 identified cladoceran taxa, the most abundant were Disparalona rostrata, Pleuroxus aduncus, and Alona affinis. Based on the diet composition, which included both bottom-dwelling and macrophyte-associated organisms, it can be concluded that racer goby feeds in a large variety of microhabitats including open non-vegetated areas, on substrates near macrophyte beds, and possibly on macrophytes.