Crows and Vocalization

Vocal Culture in New Caledonian Crows

What was the study?

The goal of this research was to study the social learning between New Caledonian crows. We have, in the past, demonstrated that birds are capable of learning and teaching vocalizations and songs across different populations, in a social way similar to how humans do. In studying the social and learning cultures of crows, we also seek to understand how they learn tool use-whether this is something that is shared socially between individuals, or learned in an alternate way.

How was this research conducted and measured?

Researchers set up recorders and hidden speakers around a measured area where they knew the crows may be roaming, keeping track of the crows seen by watching for wing tags and color rings. They first played recordings of known crow calls, in order to attract and engage nearby crows. They then played varying tracks of audio that is not known crow calls, such as short human speech phrases and clips of music. In order to solidly measure whether or not the crows mimicked the noise, they compared the spectrograms of the original recordings and the crow's recorded responses.

What did we find?

The crows would in fact mimic the sounds made by the speakers. The spectrogram comparisons found that the crows' responding calls more closely mimicked that of the played recordings, than the natural crow calls beforeand did. This shows vocal mimicry, like we know parrots most well for. There is also anecdotal evidence for this, with others that interact with crows having found the same thing. This demonstrates a form of social learning, that would also happen across crow populations, and supports the idea of crows having a vocal culture and social learning.