It’s a trap! Invasive common mynas learn socially about control-related cues

Abstract

Social learning of novel threats coupled with adaptive generalization from learned to novel cues together provide the cognitive mechanisms by which adaptive avoidance of threats can spread rapidly both within and across generations. Whereas attention to effects of fishing and hunting on prey is increasing, nothing is known about how human predation can alter the behavior of invasive animals. Here, we examined whether common (Indian) mynas, Acridotheres tristis, one of the most widespread invasive birds in Australia and invasive to many other parts of the world, are learning to respond to anthropogenic predation. We analyzed behavior at an experimental food patch provisioned by 2 distinctly clothed persons both before and after mynas had observed one of the 2 persons seemingly capture conspecifics inside a trap placed at the food patch. After the demonstration, mynas landed in smaller numbers at the food patch and took longer to land. Further, mynas alarm called more when provisioned by the person who had been involved in trapping. Future work will determine whether narrow generalization gradients are a consistent feature of synanthropic species or whether they broaden as a function of human predation threat level as is predicted by the Predator Recognition Continuum Hypothesis. Practical implications for control are discussed. Can common mynas, one of the World's most invasive birds and target of much control effort, learn to avoid trapping? After watching mynas being captured by a person who had previously fed them, observer mynas alarm called specifically to that person. They also learned the place where trapping occurred and showed generalized changes in risk-awareness. Mynas show a remarkable capacity to learn socially, which explains why they are becoming more risk-averse in areas where they are trapped.