Song or call? What’s in a bird vocalisation?

Vocalisation is a term that covers all bird sounds. We’re all familiar with the two main types of vocalisations, songs and calls, which are often used interchangeably. In fact, songs are what we recognise as typical melodious bird noises, which tend to be longer and are more complex than calls. Vocalisations are sometimes described by their function, such as songs being associated with courtship and calls being used for staying in contact and raising alarms.

 

Next time you’re listening to birds, try to identify the function of the vocalisation. Make a note of the duration of the vocalisation, how many and what type of birds are involved, and if the same calls are used in the same area. Courtship songs are often performed by males, territorial calls can be short bursts of calls between two individuals, while juvenile begging calls tend to be incessant. The alarm call is often more noticeable as more birds and different species will react.

 

Much like human language, there are many components of a bird song: song sequence, syllables, phrases and elements. Syllables are made up of one or more elements. Phrases consist of repetitions of syllables, and a song sequence is a series of phrases. These are equivalent to human words being composed of syllables, phrases to words and songs to sentences. 

 

We can learn many different things from vocalisations. Comparing call components from different species tells us that those sharing similar patterns are more closely related. Birds singing louder or at different times of day in noisy urban habitats tell us about their ability to adapt to environmental change. Sound intensity of bird vocalisations has even been used to estimate population density. 

What bird vocalisations have you heard recently?