A bird is a bird, except when it’s a nestling, hatchling or fledgling. As baby birds grow, the specific names that refer to them change, and some species even spend several years in subadult stages before they reach the sexual maturity of adulthood. These different names denote subtle changes in plumage, proportions, behavior and care needs that can help birders properly identify baby birds. It’s time to refresh our vocabulary!
Hatchling: It hasn’t yet opened its eyes, and may have wisps of down on its body. It’s not ready to leave the nest.
Nestling: Its eyes are open, and its wing feathers may look like tubes because they’ve yet to break through their protective sheaths. It’s also not ready to leave the nest.
Fledgling: This bird is fully feathered. Its wings and tail may be short, and it may not be a great flyer, but it can walk, hop, or flutter. It has left the nest, though its parents may be nearby, taking good care of it.
Not all baby birds are born with feathers. Feathers are vital to birds, but many baby birds are born nearly bald.
- Altricial babies grow their feathers quickly after hatching, but require more parental care to stay warm and healthy. (see the Eastern Bluebird Hatchling picture above).
- Precocial baby birds, such as ducks and geese, are born with soft down feathers and can leave the nest to forage just hours after hatching.
When talking about the age of a bird, the terms juvenile and immature are not interchangeable.
- Juvenile: Strictly speaking, one should only refer to a bird as a juvenile during the period when it wears its first complete set of feathers. Once a bird begins to replace feathers from the original set, it is no longer a juvenile.
- Immature is a general term for any non-adult plumage, including juvenile plumage.
What is branching versus fledging?
- Branching refers to the hopping about and jumping from branch to branch around the nest. Fledging refers to the bird’s first flight and generally results in the bird landing in a different tree or on the ground. Eagles and owls usually have branching prior to fledging. This allows the growing birds to stretch and test their wings without actually flying. At times, a branched bird falls before it can fly to return to its nest. The parents may care for that bird on the ground until it can fly or it may be a mortal situation.
Wilson Plovers leave their nests soon after hatching. Brown Pelicans Young leave ground nests after about 5 weeks and gather in groups, where returning parents apparently can recognize own offspring. Neither of these is considered branching but these young chicks also have not fledged as they have yet to fly.
We hope this article was informative. Do you have any other names for young birds? Let us know if there are other topics about birds you are interested to learn more about!
Article submitted by Judy Morr