Role of the round goby (Neogobius melanostomus) in the food web of the south-eastern Baltic Sea coastal waters

• Main Author: Skabeikis, Artūras
• Other Authors: Lesutienė, Jūratė
• Format: Doctoral or Postdoctoral Thesis
• Language: Lithuanian; English
• Published: Institutional Repository of Klaipeda University 1481
• Subjects: biotope type; invasive species; food competition; predation; ECOPATH model; Turbot
• Online Access: http://ku.oai.elaba.lt/documents/39072875.pdf; http://ku.lvb.lt/KU:ELABAETD39072875&prefLang=en_US

This study provides the first comprehensive research on the functional role of the invasive round goby in the food web of the SE Baltic Sea coastal ecosystem. The round goby invasion success was determined by evaluating its abundance, morphometric/biological parameters and contribution in the fish communities from the stony and sandy biotope types. The diet composition of the round goby and its feeding niche overlap with the native benthophagous flounder, eelpout and vimba bream was evaluated by applying the gut content and stable isotope analyses. The round goby vulnerability to the piscivorous fish was determined by performing the stomach content analysis of the cod, turbot, shorthorn sculpin and perch. The ECOPATH model was employed to reveal the trophic position of differently sized round gobies and their effects to other food web compartments. The results of the present study suggested that the round goby became a key component of the coastal food web. It posed a detrimental impact on the blue mussel population and the wintering site quality of the benthophagous long-tailed ducks, but positively affected piscivorous fish/waterbirds and coastal fishery as an important forage/commercial catch species.