Mesocosm_data

Our study aimed to estimate synergistic effects of higher level fish predator, <i>Babka gymnotrachelus</i>, and stronger interspecific competitor within same guild, <i>Dikerogammarus villosus</i>, on population dynamics of prior invader, <i>D. haemobaphes</i>, all originating from the Ponto-Caspian region. We hypothesized that abundance and distribution of <i>D. haemobaphes</i> would be negatively affected by introduction of <i>D. villosus </i>and fish in the tank, either alone or simultaneously. To verify, we conducted mesocosm and laboratory experiments simulating their invasion sequence in continental Europe. Our study underlines differences in species-interaction strength depending on ontogenetic stage, which is often omitted in models of biological invasion dynamics and impact. Finally, we provide experimental evidence demonstrating how negative interactions among invasive species can dominate and shape community structure.