When young birds leave the nest, they are fed by one or both parents for a certain period, and give "begging" calls at this time, some of which are amongst the most commonly heard calls in the summer months. The calls are species-specific and change as the nestlings/fledglings age. Some sounds appear to function as location calls, and others as calls that say "feed me". Often the calls increase in rate as a parent approaches with food, or there may be a switch to a different call at the point of feeding. Fledglings of at least some species, such as American Robins, appear to have a fairly extensive vocabulary, and I've observed families of young Gray Catbirds making different vocalizations, perhaps to identify themselves individually to the parents ( see Gray Catbird fledgling calls).
The location call of fledgling Eastern Kingbirds is identical to a call used as an alarm by the adults. When being fed, they switch to a soft screeching call. In this recording, one young bird is giving the location call while another is giving the begging call as it gets fed by an adult (July, PA).
location and begging calls
A family of Great Crested Flycatchers, with the young birds using the wheep call (July, PA).
Young Great Crested Flycatchers can make a tremendous din. Here are several calling from high in trees (July, PA). They already have the full array of adult calls as they are not learnt.
purrit and rasp calls
Quieter calls by a fledgling Great Crested Flycatcher, with begging calls at 35-45s (July, PA).
some of the calls are not typical adult calls
begging calls at point of being fed
Eastern Wood-Pewee juvenile calling and being fed at 10 to 17 seconds. There are three call types, a short, high pwe, a hoarse call which increases in rate and intensity at the point of feeding, and intermediate calls (Aug, NJ).
intermediate and wheezy call
wheezy calls at point of being fed
Another call by a lone fledgling Eastern Wood-Pewee, a hoarse pewee (July, PA).
Calls by three newly fledged Acadian Flycatchers which were perched together up in a tree (Aug, PA).
Calls made as an adult brought food:
Another juvenile Acadian Flycatcher (July, PA).
Warbling Vireo fledgling calls. They are similar to the adult alarm calls but shorter (July, PA).
American Crow fledglings have more nasal calls than adults, recalling Fish Crow, but the calls are not doubled. Gulping sounds at 7 and 35s when being fed (July, ME).
Juvenile Blue Jay calls at point of feeding (June, PA).
Juvenile contact calls and then calls at time of feeding, adult contact calls at end (June, PA).
juvenile contact call
adult contact call
Jay call by a fledgling Blue Jay (with adult, June, PA).
These older juvenile Blue Jays sound a little like hoarse adults (Jul, ME).
The fledglings of the following three species of swallow have calls that sound like those of adults.
Tree Swallow fledglings perched high in a spruce (June, PA).
Northern Rough-winged Swallow fledglings perched in a small dead tree (June, PA).
Fledgling Barn Swallows in flight (June, PA).
Tufted Titmouse juveniles have three calls, one a descending call (probably a location call, that recalls the flight and juvenile call of the Field Sparrow), an intermediate call, and squeaky begging calls that are similar to those of chickadees (June, PA).
Another fledgling Tufted Titmouse (July, PA).
Juvenile Black-capped Chickadees (July, ME).
Juvenile Carolina Chickadee (July, PA).
Compare with the begging calls of an adult female requesting food from a male (early May, NJ).
Brown Creeper fledglings have clear, long, descending calls (July, ME).