Personalities are interindividual behavioral differences which apply across the animal kingdom. Measuring boldness through foraging behavior may be a more universal, bottom-up approach than traditional assays. We assessed exploratory tendency and boldness in an invasive and native crayfish using two personality assays and compared them to foraging efficiency as measured by giving-up densities (GUDs). We predicted that 1) Invasive crayfish would be more exploratory, bolder, and have lower GUDs than native crayfish, 2) crayfish would show intraindividual consistency and interindividual variation across foraging trials, and 3) crayfish that ranked bolder in traditional assays would have lower GUDs.
Results/Conclusions
Crayfish were consistent across time within all three behavioral measurements, and there was significant interindividual variation. There was little correlation between behavioral assays, but cluster analysis and PCA showed GUDs were more closely related to latency to explore a novel environment, while aggressiveness towards a novel object was more closely related to size measurements. Native crayfish had higher GUDs, but were more aggressive towards a novel object. These results suggest invasion success is more closely associated with ability to outcompete native congeners for food items than with boldness, and that GUDs measure foraging-associated traits separate from those measured by traditional boldness assays.