Performance of blue-fronted amazon parrots (Amazona aestiva) when solving the pebbles-and-seeds and multi-access-box paradigms: ex situ and in situ experiments.

Birds can solve many cognitive tasks that were previously only solved by primates, implying that their cognitive ability is far greater than expected. Here, we investigated the ability of blue-fronted amazon parrots in solving the pebble-and-seed and the multi-access-box paradigms, two ecologically relevant cognitive tasks varying in complexity and required skills to solve. We also investigated whether laterality, sex and housing conditions influenced problem-solving capacity. We tested 14 adults kept in captivity and 27 reintroduced adults. Here, we present evidence of laterality for the species, showing right-footed, left-footed and ambidextrous individuals. Left-footed animals were more successful than the right-footed animals in the pebble-and-seed test. There was no sex difference in the problem-solving capacity of the blue-fronted amazon parrots for both pebble-and-seed and multi-access-box paradigms. Eleven captive animals were successful in at least one of the four multiple-access-box possible solutions. Four reintroduced individuals were successful in at least one of the multiple-access-box possible solutions. Only two captive animals and one reintroduced animal succeeded to solve more than one of the four multiple-access-box solutions. The average success rate of the pebble-and-seed test was 88.16% ex situ and 86.58% in situ, with individual variation in test-solving ability. Our study shows that unlike laterality, sex was not determinant in blue-fronted amazon parrots' problem-solving ability. The blue-fronted amazon parrots have the visual discrimination skills needed for the pebble-and-seed task solution, and the motor skills for beak-foot coordination and potentially understanding of complex spatial relationships required for the string-pulling task, the multi-access-box solution achieved by most of the animals. Our results increased the knowledge of the cognitive ability of parrots, a group which lacked extensive cognition data.