Animal Cognition

, Volume 21, Issue 1, pp 55–65 | Cite as

Exploratory behavior of a native anuran species with high invasive potential

  • Amanda J. Miller
  • Rachel A. Page
  • Ximena E. BernalEmail author
Original Paper


Exploratory behavior can be a key component of survival in novel or changing environments, ultimately determining population establishment. While many studies have investigated the behavior of wild animals in response to novel food items or objects, our understanding of how they explore novel environments is limited. Here, we examine how experience affects the foraging behavior of a species with high invasive potential. In particular, we investigate the movement and behavior of cane toads as a function of experience in a novel environment, and how the presence of food modulates exploration. Cane toads, from a population in their native range, were repeatedly tested in a large, naturalistic arena with or without food present. Both groups exhibited significant but different changes in exploratory behavior. While toads in an environment without food reduced exploratory behavior over trials, those with food present increased both food intake per trial and the directness of their paths to food, resulting in fewer approaches to food patches over time. Our results suggest that cane toads learn patch location and provide preliminary evidence suggesting toads use spatial memory, not associative learning, to locate food. In sum, we show that with experience, cane toads alter their behavior to increase foraging efficiency. This study emphasizes the role of learning in foraging in cane toads, a characteristic that may have facilitated their success as invaders.


Rhinella marina Bufo marinus Spatial learning Exploration Foraging success Resource tracking 



Funding was provided by the Association of Biologists at Texas Tech University, and the HHMI Center for the Integration of Science Education and Research to AJM. We are grateful to the Smithsonian Tropical Research Institute for use of lab facilities and equipment, to Rich Strauss for his advice concerning statistical methods, and to Damond Kyllo for his cane toad drawing. H. Miller, N. Lewis, M. Hein, M. Harris, E. Braverman, and H. Russon provided invaluable help scoring toad behavior on videos. Two anonymous reviewers and K. Cheng provided constructive criticisms and suggestions that greatly improved the quality of this study.

Supplementary material

Supplemental video 1

Illustration of escape attempts. Three different instances of a toad trying to escape the arena are shown (MP4 852 kb)

Supplemental video 2

Video recorded during preliminary trials illustrating the behavior of toads when eating. In contrast to the design in the experiment of the study, the toad is here shown eating from a bowl in which multiple mealworms were presented. This set-up was not selected given that when mealworms crawl on each other, they produce acoustic cues that could be perceived by the toad (MP4 336 kb)


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Copyright information

© Springer-Verlag GmbH Germany 2017

Authors and Affiliations

  1. 1.Department of Biological SciencesTexas Tech UniversityLubbockUSA
  2. 2.Smithsonian Tropical Research InstituteBalboa, AncónRepublic of Panama
  3. 3.Department of Biological SciencesPurdue UniversityWest LafayetteUSA

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