Eat first, fight later: competitive advantage of an invasive cichlid over a native competitor for food resources

Data used in the analysis of the manuscript "Eat first, fight later: competitive advantage of an invasive cichlid over a native competitor for food resources.

Abstract: Competition for resources between invasive and native species may lead to negative impacts on native fauna. Behavioral interaction is commonly used by aggressive species to monopolize resources, while invasive species may exhibit higher aggressiveness than native competitors. We evaluated how food resource availability influences agonistic interactions between the invasive Cichlid Oreochromis niloticus and the native Cichlid Geophagus iporangensis, assessing whether the invasive species interferes behaviorally with the native species' feeding activity. We tested a competition scenario in neutral arenas, initially without food, followed by the introduction of food resources. The native Cichlid, used as the focal animal, was exposed to either an invasive or a conspecific competitor. Aggressiveness was higher in the absence of food resources. The aggressiveness of the invasive species did not affect the feeding rate of the native species, and no behavioral interference was observed. Scramble competition was the primary strategy employed by the invasive species to maximize food intake, displaying a sevenfold increase in food consumption than the native species and initiating feeding first in 9 out of 10 trials. Our findings suggest that even for aggressive invasive species, feeding behavior and resource exploitation may play a key role in the competitive exclusion process.