The Role of Stimulus Complexity and Experience in the Expression of Exploratory Behavior in a Generalist Bird of Prey, the Chimango Caracara (Milvago chimango)

BIONDI L. M.; GUIDO J. M.; BÓ M. S.; MUZZIO, RUBÉN; VASSALLO A. I.

Congreso; I WORLDWIDE RAPTOR CONFERENCE; 2013

Exploration represents an important way by which organisms evaluates the environment information, and learn about its properties. Animals are increasingly exposed to novel environmental conditions because of human activities. The decision of whether or not an animal should investigate environmental changes involves a trade-off between the risk and the potential benefit of novel resources. The resultant decision may influence the extent to which animals learnt about their surroundings. We analyzed in a Neotropical raptor, the Chimango Caracara, Milvago chimango (thereafter, Mch) how external (complex vs. simple objects) and internal factors (with vs. without experience with similar objects) might influence novel object exploration based on either cost-benefit considerations. Our findings showed that in Mch complexity did not affect the initial exploratory response: a similar percentage of adults and juveniles explored both simple and complex objects, as well as the time until approach and contact the objects did not varied between object types. However, total exploration time and number of exploratory events were higher for complex than simple objects, particularly in juvenile birds. These results indicate that the decisionmaking process regarding exploration in Mch was guided more by the benefits of a higher quantity of information provided by exploring complex objects, compared to simple ones, than by the risks associated to this activity. Experience led to a decrease in exploration only when simple objects were in play. It is probably that for Mch simple elements were easier to process and recall than complex ones, so a further exploration of such objects would not provide additional benefits. We can conclude that Mch cope with novel features of their surrounding with a novelty-seeking strategy, characteristic that for a generalist species, like Mch, is critical for discovering early changes signaling new resources opportunities, and might be a determining factor for the ability to respond adaptively to environment modifications.