Why Birds Call
In addition to singing, birds use a variety of sounds to communicate. Calls are used for interacting with family members, alerting one another to the presence of predators, keeping in touch while flying, or sharing information about food.
I'm here, where are you?
Birds use contact
keep in touch with as they fly, feed, or go about their
day. Contact notes are often short and high-pitched. Listen
to the complex song of a Song Sparrow, followed by its contact
The contact call of some
species is sometimes its most conspicuous vocalization, such as the per-chik-o-ree
call of American Goldfinches. Mates can match
each other's calls, helping them to identify their partners, even at a distance or in a large flock.
Listen to the song and contact calls of an American Goldfinch.
Many birds use contact calls to keep in touch while migrating. For example, geese honk as they fly. Birds that migrate at
night may use nocturnal flight calls.
Some very experienced birders can tell which species are flying overhead by
listening to the these sounds. Researchers at the Cornell Lab of Ornithology are using these sounds to study birds at night: monitoring the numbers and kinds of birds that pass overhead during migration.
Many birds utter alarm calls in response to a nearby predator. Jays, domestic chickens, and many other birds even use different calls for warning about ground and aerial predators. For example, Florida Scrub-Jays use a thin, high-pitched call for a hawk or falcon, prompting nearby jays to dive for cover. They use a lower pitched, scolding sound when warning of a snake, cat, or other terrestrial predator. These calls incite other jays to join in mobbing the intruder--swooping down at the predator to drive it away.
Black-capped Chickadees give a chick-a-de-de-de alarm call. Recent studies have found that in some areas, the number of des varies depending on how severe the chickadee believes the threat to be. The greater the threat, the more des the chickadee uses in its call.
By using alarm calls, birds let the predator know it
has been sighted. Having lost the advantage of surprise, the predator
may decide to give up the attack. Alarm calls also warn other birds
that the predator is there. This may help because birds will often mob
predators that are near their nests or young. When birds of many
species join in, they have a better chance of chasing the predator
away. Alarm calls also help by warning the caller's young, mates, or
relatives to take cover.
Some birds use calls to announce that they have found food. In
Nebraska, Cliff Swallows forage for aerial insects in groups of 2
to more than 1,000 birds. When birds find food in bad weather, they use
a squeak call that attracts other swallows. Keeping track of a moving
swarm of insects may be difficult for a single swallow. Attracting
other swallows may improve its chances of continuing to find food.
I'm hungry—feed me!
Baby birds use begging calls
to let their parents know they're hungry. Many songbirds continue
to use begging calls even several weeks after they leave the nest, and
their parents oblige. Juvenile Cliff Swallows beg distinctively enough for their own parents to recognize them individually. Cliff
Swallows often nest in colonies with hundreds or thousands of other
swallows, so it's important for them to be able to find and recognize
their own young after they leave the nest.
Next step: How birds develop their vocalizations