Public information use—are invasive demersal fish species more effective than natives?

Abstract

Abstract Organisms determine environmental quality using their senses and personal experience (personal information) but can also use byproducts of other individuals’ activities (i.e. public information). The ability to use public information originating from both con- and heterospecifics gives an advantage over individuals relying only on personal information or conspecific cues. The role of public information in invasion ecology is of high concern, as any differences in this aspect between alien and native species may determine the success of the former. Here, we studied 2 pairs of sympatric invasive and native demersal fish species (racer goby Babka gymnotrachelus/European bullhead Cottus gobio; monkey goby Neogobius fluviatilis/gudgeon Gobio gobio) facing 2 types of public cues (associated with antipredatory and foraging behavior). We used them as a model to check if the invaders could use public information from more sources than the natives. Both invaders and the native gudgeon used cues from con- and heterospecifics, exhibiting antipredatory behavior, while the native bullhead failed to recognize such cues from heterospecifics. The monkey goby and both native species were attracted to foraging cues from donors less likely to exert competitive pressure on the observer (i.e. native species rather than potentially more aggressive invaders). On the other hand, the racer goby appeared unable to correctly recognize heterospecific foraging cues. Our results showed that public cues can enable invaders to read threat from a wide range of individuals and to find optimal food patches, which may contribute to their invasion success.