All parents know that babies have a glossary all their own, and baby birds are no different. By understanding these basic terms related to baby wild birds, it is easier to identify them and to care for them appropriately.
Click on any term for a more detailed definition.
Describes birds that hatch nearly naked and blind, requiring extensive parental care to mature. Most songbirds are altricial, but they develop feathers and independence rapidly.
A set of related eggs that are laid and hatched together. Mated pairs of birds may raise more than one brood in a season if climate, food and health conditions are adequate.
A bare patch of skin on a nesting bird’s chest, abdomen or sides. This skin has more blood vessels and can more easily transfer the parent’s body heat to the eggs they are incubating.
An excreted gelatinous sac that contains a hatchling’s feces. Very young birds may excrete fecal sacs to help keep the nest clean, and parent birds will dispose of the sacs accordingly.
A young bird that has developed preliminary flight feathers and is ready to leave the nest. Full adult plumage may not be developed, but the bird is independent enough to begin flying.
A very young bird, usually just hours or one or two days old. This is a more generic term that can apply to any recently hatched bird, regardless of species. Hatchlings require intense parental care.
The act of using body heat to keep eggs at an optimum temperature for healthy development and hatching. Parent birds may share incubation duties, or the female bird may do most of the incubating.
A young bird, typically covered with soft down, that has not yet developed its flight feathers and is not ready to leave the nest. Nestlings typically require moderate to intensive parental care and protection.
Describes birds that hatch with open eyes and a covering of down. These birds have a higher degree of independence and can leave the nest within hours or just a few days, though they still require moderate parental care and guidance.
Describes birds that are nearing maturity but are not yet sexually mature and lack some fully adult characteristics, such as distinct plumage. Subadult species usually take several years to reach full maturity.