[1][2] For altricial birds, those that spend more time in vulnerable condition in the nest, the nestling and fledging stage can be the same.
A young bird that has recently fledged but is still dependent upon parental care and feeding is called a fledgling.
In many species, parents continue to care for their fledged young, either by leading them to food sources, or feeding them.
Birds are vulnerable after they have left the nest, but before they can fly, though once fledged their chances of survival increase dramatically.
[5] One species, the ancient murrelet, fledges two days after hatching, running from its burrow to the ocean and its calling parents.