Ruth Naughton, age 10, of Helena, Mont., for her question:
HOW LONG WILL AN EAGLE LIVE?
Wild eagles usually live from 20 to 30 years. In captivity, eagles may live 50 years and even more.
Young eagles breed for the first time when they are about 4 years old. They keep the same mate for life but if one dies, the other usually finds another mate and breeds again the next year.
In winter, a large group of eagles usually gathers in areas where there is plenty of food available. But during the breeding season in spring, each pair claims territory around the nest and keeps all other eagles away.
The golden eagle defends a territory that covers between 20 and 60 square miles. The bald eagle holds a smaller territory. Sometimes three bald eagles' nests lie within one mile of each other.
The nests of eagles are called "eyries" or "aeries." Both spellings of the word are pronounced the same way: "air eez."
Bald eagles usually build their eyries in the tops of tall trees that are near the water. Some nests are built on cliffs.
Golden eagles usually build their eyries on steep cliffs in the high mountains.
Eagles build eyries mainly with sticks and they come back to the same nest year after year. They often decorate the eyrie with fresh green leaves while they are using it: Then they add new material every year they use it, so many old eyries are very big. A new eyrie may be only three feet across and 18 inches deep. But an old eyrie may be about 10 feet across and as much as 20 feet deep.
Eagle eggs are about three inches long and two inches across. Females usually lay two eggs each year, but rarely do they lay three. Golden eagle eggs are white or spotted with reddish brown or gray while bald eagle eggs are white, but become stained with yellow while in the nest.
Northern eagles lay their eggs in March. Bald eagles in Florida lay eggs in September or October. The eggs of eagles must be warmed for about 40 days before they hatch.
The female eagle will sit on the eggs during most of the time it takes for them to hatch. The male sits on them occasionally and brings food to the female while she is sitting.
Both parents guard the nest and take food to the young.
Eaglets are hatched with their eyes open. They are covered with grayish white fuzz. Their feathers start to grow when they are about four weeks old.
Eaglets are not able to tear up their own food until they are six or eight weeks old. They cannot fly very well when they leave their eyries at 11 or 12 weeks of age. Their parents continue to feed them for several months more until they can hunt well enough to get food on their own.
There are 48 kinds of eagles in the world but only the bald eagle and the golden eagle breed in the United States and Canada.