High background risk induces risk allocation rather than generalized neophobia in the fathead minnow

To cope with the heterogeneous nature of predation and the trade-off between predator avoidance and foraging, prey animals have evolved several cognitive rules. One of these is the risk allocation hypothesis, which predicts that in environments with long periods of sustained high risk, individuals should decrease their antipredator effort to satisfy their metabolic requirements. The neophobia hypothesis, in turn, predicts increased avoidance of novel cues in high-risk habitats. Despite the recent interest in predator-induced neophobia across different sensory channels, tests of such generalized neophobia are restricted to a single fish taxon, the Cichlidae. Hence, we re-tested the generalized neophobia hypothesis in fathead minnows Pimephales promelas, a small schooling North American cyprinid fish. From hatching onwards, minnows were exposed to conspecific alarm cues, which indicate predation risk, or distilled water in a split-clutch design. After one month, shoaling behavior was exam...