In Alaska, seeing a bald eagle swooping overhead is magical, if not relatively common. In New York City, it’s a minor miracle.

An elated New York City Audubon announced that a pair of bald eagles has been spotted with what appears to be an active nest on the South Shore of Staten Island, making them the first of the species to incubate eggs in the Big Apple in 100 years.

“The eagles are engaging in brooding behavior typical of nesting birds incubating their eggs,” explained Tod Winston, communications manager and research assistant for NYC Audubon. “Due to the height and location of the nest, it is not possible to actually see into it from the ground.”

The world won’t have to wait too long to see if the birds have successfully started a family. A normal incubation period for the bald eagle is between 34 and 36 days. Both male and female will take turns sitting on the eggs. If the eggs hatch, for the first two weeks of life, at least one parent will stay with the newborns. The one not watching the babies will hunt for prey to feed the family. To see the juveniles fly, we’ll have to wait between 10 and 12 weeks.

Tourists won’t be visiting the nest of this mating pair anytime soon. New York City does not reveal the exact location of bald eagles to help protect them from large crowds and poachers.

The Audubon reports that it is excited about the bald eagles that are establishing roots in the United States’ most populated city, speculating that there are two reasons for the birds’ change of behavior. The local ecosystem is less polluted than it once was, making it a friendlier habitat, and the bald eagle population has rebounded so well that some birds are moving out of more rural areas and into the city.

In 1963, the bald eagle hit its lowest numbers in the U.S. with only 417 documented mating pairs in the lower 48 states, according to NPR. DDT, a pesticide commonly used in the '40s, contaminated lakes, streams and eventually fish, the eagles’ preferred food. DDT was found to weaken the eggshells. The pesticide, in combination with deforestation and illegal shooting, led to the near extinction of the species.

Due to the low numbers, the bald eagle was declared an endangered species in 1967, even before the Endangered Species Act passed in 1973. In what is considered a great success story, the birds were removed from the endangered species list in 2007, having rebounded to nearly 10,000 mating pairs.

In the wild a bald eagle can live between 15 and 25 years. Many couples mate for life, often returning to the same nest year after year. The birds don’t acquire that telltale white feathered head until they reach 4 or 5 years of age. Before that, the juveniles are mostly brown, and because of their coloring, can be confused with the golden eagle.

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