A fledgling (occasionally misspelled as fledgeling) is a young bird that has grown enough to acquire its initial flight feathers and is preparing to leave the nest and care for itself. Young birds that have already left the nest but do not yet have all their adult plumage and are still fed by the parent birds for several days are also referred to as fledglings. The term is generally used only for passerines, however, not for precocial birds such as ducks, geese, quail, or shorebirds that leave the nest very quickly but still require intense parental supervision and care.
Is This Bird a Fledgling?
It can be difficult to identify when a bird has matured into the fledgling stage, but there are clues. When examining baby birds, look for:
- Feather Length
Flight feathers on a fledgling’s wings and tail look significantly shorter than they will on adult birds. These larger feathers take the longest to grow out, and even after these birds have left the nest their wings and tail may have a stubby or stunted appearance. Their feathers could also appear uneven or rumpled.
- Bill Size
A fledgling’s bill often looks larger or more brightly colored than an adult bird’s bill. A young bird has a very bright gape to attract attention when their parents bring food to the nest, and even after fledglings have left the nest, that color takes some time to fade. At the same time, however, other colors, such as brightly colored legs or bare skin patches, may be duller on fledgling birds.
- Clumsy Flight
Young birds have uncertain flight skills such as difficulties with takeoffs, landings, quick turns, or distance flight. Fledglings are capable of flying but don’t yet have a lot of practice, so they may seem clumsy or reluctant to fly, even if closely approached. As they practice, however, they will quickly gain more skill for smoother, more coordinated flight.
- Attentive Parents
When young fledglings first leave the nest, their parents will remain nearby and will return frequently to feed the youngster, and the young bird may cry and beg when the parents are near. It may seem that the baby bird has been abandoned, but in fact the parents are well aware of their chick and are taking care of it.
What a Fledgling Isn’t
There are many stages of baby bird growth and maturity, and it is important to recognize other growth stages so they are not confused with fledglings. Birds in the nest without any flight feathers and that are still completely dependent on their parents, for example, are generally called nestlings, even if they have developed some feathers and are more active. Other bird life stages that are often confused with fledglings include:
- Juvenile Birds: These are slightly older birds that may still have some fledgling markings or coloration, but their flight feathers are nearly fully developed and they are able to feed themselves well. These birds do not rely on their parents any longer, though they may stay in small family groups until they are fully mature and seek their own mates. The juvenile stage can last several weeks or months until these young birds molt into full adult plumage and will then be indistinguishable from their parents.
- Subadult Birds: Some birds with longer lifespans, including gulls and raptors, molt through several different plumages before they reach their full adult coloration and markings. Each of these stages is a different subadult stage, but these birds are no longer fledglings. A subadult bird is usually the size of a full adult and can fly well, feed itself, and perform other tasks without parental assistance. These birds may no longer associate with their parents in any way, but are not yet seeking their own mates. It may take several years for birds to mature through different subadult stages until they are fully mature adults.