Differences in neophobia between cane toads from introduced and native populations

Abstract

For species moving into new environments, locating and using unfamiliar resources is crucial for survival. The cane toad (Rhinella marina) has been successful in many countries worldwide, persisting in both urban and rural landscapes. Given that animals exploiting urban habitats are confronted with novel feeding opportunities, individuals in those areas are expected to exhibit reduced neophobic tendencies compared with individuals in rural populations. Additionally, individuals persisting in introduced populations are expected to be less neophobic than individuals in native populations, taking advantage of novelty as their range expands. To investigate such predictions, we examined the response to novel prey and a novel object in native toads in Panama and introduced populations (urban and rural) in Florida. Toads were tested in an arena with novel or familiar prey and later with a novel object next to familiar prey. We found differences in response to novelty between cane toads in different ranges but not in different habitats. Most introduced individuals from both urban and rural habitats consumed novel prey with no difference in latency to eat between prey types. Few native toads, however, consumed any prey during trials, spending most of their time moving about the arena. When familiar prey was presented near a novel object, more than half of the introduced toads ate, but no native individuals ate. This study emphasizes the importance of behavior as a mechanism used by invasive species to exploit novel resources and successfully colonize new environments.