Innovation and decreased neophobia drive invasion success in a widespread avian invader

Abstract

Certain behavioural traits, including innovation and reduced neophobia, may facilitate successful invasions by allowing first arrivals to overcome the challenges of a novel environment. However, the extent to which these traits occur in invasive populations in comparison with native populations, and whether these traits' prevalence remains consistent throughout a species’ introduced range, have been scarcely investigated. We tested whether object neophobia, food neophobia and two levels of motor innovation in the common myna, Acridotheres tristis, a widespread avian invader, in its native range (India) as well as across an invasive range (Israel), are more prevalent at the edge of the invasion front relative to its centre and to the native ranges. We found that individuals from the invasion front were more innovative and more tolerant of novel food than those from both nonfront invasive populations and the native range. Moreover, these traits showed a gradual loss within the invasive population with increasing time since population establishment. Our results provide crucial empirical evidence to support the adaptive flexibility hypothesis for invasion processes and emphasize the role of behaviour in biological invasions.