Question: What's the difference between a precocial bird and an altricial bird?
Answer: A precocial bird can move around on its own soon after hatching. An altricial bird is not capable of moving around on its own soon after hatching.
There isn't a distinct dividing line between the two, but it is instead more of a gradual shift from one to the other. There are four basic categories:
Precocial birds are hatched with eyes open, covered with down, and typically leave the nest within two days. Some may follow parents and get their own food (ducklings), some may follow their parents and are shown food (bobwhite, right), and some may follow their parents and are shown food and fed by the parents (limpkin, left).
Semiprecocial birds are hatched with eyes open, covered with down, and capable of leaving the nest, but they stay by the nest and are fed by the parents. This is true of most gulls and terns.
Semialtricial birds are covered with down, incapable of departing from the nest, and fed by the parents. Some, like hawks and herons, hatch with their eyes open. Others like owls hatch with their eyes closed.
Altricial birds are hatched with eyes closed, with little or no down, incapable of departing from the nest, and are fed by the parents. All passerines are altricial.
Pronounciation: precocial (pri - ko' - shul) -- altricial (al - trish' - ul)