1) Reaching maturity 
• (p. pr. & vb. n.) of Fledge
The act of leaving the nest. See fledgling.
Term commonly used to describe the time at which nestlings that are reared in the nest leave the nest, even though their flight abilities may not yet be well developed. But, the term is sometimes used to describe the time at which a young bird has finished acquiring its first complete set of flight feathers—generally the time at which it is capab...
A young bird that has learned to fly.