Bird Songs & Calls
If you have a yard or garden, chances are you have plenty of birds. Each one has its unique sounds, songs and calls. Not all birds actually sing; this is limited to the perching birds so nearly half of all birds in the world do not sing. Instead they make other sounds to communicate.
Bird Calls versus Bird Songs Most birds use vocalizations which are short and unmusical and cannot be termed as song. These sounds have considerable functionality and are generally labeled call-notes or calls to distinguish them from true songs. Call sounds can be classified into these categories: 1- General alarm calls 2- Specialized alarm calls 3- Distress calls 4- Aggressive calls 5- Territorial defense calls 6- Flight calls 7- Nest calls 8- Flock calls 9- Feeding calls 10- Pleasure calls Sound is often more important than sight in parent-offspring recognition. A deaf female turkey is unable to recognize her own chicks and chickens cannot recognize silenced chicks (with a bell jar over them). Experiments have also shown that, in colony nesting birds at least young birds can recognize their own parents by their calls alone, though they all sound the same to us. Birds start using calls early in their lives, in some species even before they are hatched. Quail chicks use calls to communicate with each other and their mother from inside their eggs. They are able this way to synchronies their hatching so that they all emerge from the eggs within the space of a couple of hours. Bird songs: Where do birds get their song from? Research has shown that it is a mixture of innate, pre-programmed knowledge of what their species song is and learning from older singing males. Some species of birds show definite learning skill; they sing a song that is a bit of mess at the beginning of their first season, but after a couple of weeks of practice become much better at singing the species' anthem. Males sing for two reasons, and the message depends upon who is hearing the song. Male birds establish and defend a territory from other males of the same species by singing from perches around and within the territory. In this sense, song is a keep-out signal. Other males know that if they violate a territory's boundary, they will be attacked. A second reason males sing is as an invitation to females. Furthermore, a single male can create the illusion that a territory is overrun with competing males, and therefore undesirable, by singing from many perches within the territory.
Mockingbirds, for example, which have an extensive repertoire of songs, sing a different song whenever they move to a new perch.
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