String-pulling in spectacled parrotlets (Forpus conspicillatus)

Abstract

[The aim of this study was to test the cognitive abilities of spectacled parrotlets ( Forpus conspicillatus ) with a means–end problem. For this purpose a group of parrotlets was presented with an experimental design, the 'string-pulling task', frequently applied to test the problem solving abilities of birds or mammals. Analysis of data collected during our tests revealed the following results: (1) The spectacled parrotlets are able to obtain food suspended on a string. (2) There was no evidence for any trial-and-error learning, because the latency of string-pulling activities did not show an experience-related modification. (3) There was also no evidence for any learning through imitation, because the performance quality did not show any improvement related to the time. (4) There was no indication that the birds' string pulling was a kind of pre-programmed behaviour, because individuals used different manoeuvres or techniques, respectively, when engaged in string-pulling activities. Thus, spectacled parrotlets are well able to understand and solve a physical problem which is the first step to a means–end comprehension shown in other bird and mamalian species., The aim of this study was to test the cognitive abilities of spectacled parrotlets ( Forpus conspicillatus ) with a means–end problem. For this purpose a group of parrotlets was presented with an experimental design, the 'string-pulling task', frequently applied to test the problem solving abilities of birds or mammals. Analysis of data collected during our tests revealed the following results: (1) The spectacled parrotlets are able to obtain food suspended on a string. (2) There was no evidence for any trial-and-error learning, because the latency of string-pulling activities did not show an experience-related modification. (3) There was also no evidence for any learning through imitation, because the performance quality did not show any improvement related to the time. (4) There was no indication that the birds' string pulling was a kind of pre-programmed behaviour, because individuals used different manoeuvres or techniques, respectively, when engaged in string-pulling activities. Thus, spectacled parrotlets are well able to understand and solve a physical problem which is the first step to a means–end comprehension shown in other bird and mamalian species.]