The first whooping crane to be born in the wild in the United States in 60 years hatched somewhere near the Kissimmee Prairie of central Florida last week.
It was followed about three days later by another one, to the delight and amazement of biologists who have been monitoring the nest around the clock.
The pair are the first whooper chicks to be born in the wild east of the Mississippi since the turn of the century.
Marty Folk, one of the state biologists who for the past month had been watching the nest from about 200 metres away, got a glimpse of the two chicks Sunday. He saw "a little speck of orange moving around at the foot of the parents. . . . It was kind of a monumental thing," he said.
"We are very, very, very excited about this," said Joy Hill, a spokeswoman for the Florida Fish and Wildlife Conservation Commission. "This is the culmination of a dream for many people."
The excitement is tempered by the fact the chicks are likely to be gobbled up by a predator in the next two weeks, carried off by a hawk or swallowed by a snake. In studying the whoopers' cousin, the sandhill crane, biologists have learned that only one chick out of 10 survives longer than two weeks.
Last year marked the first time a pair of the endangered birds laid eggs in the wild. Whooper nests are constructed to be floating platforms anchored to the marsh vegetation. That makes them vulnerable to predators.
Before last year's eggs could hatch, they disappeared, apparently eaten by a snake or an alligator.
But it wasn't snakes and alligators that put the whooping crane on the endangered species list.
Once thousands of the majestic birds soared across the United States, their call audible up to three kilometres away. But as settlers drained marshes and plowed prairies, the birds' numbers dwindled rapidly.
By 1938, only two small flocks remained. One nested in Canada and wintered in Texas. The other lived year-round in Louisiana. A storm wiped out all but six of the Louisiana birds, and none laid eggs again. The last survivor of that flock died in 1950.
Researchers desperate to save the birds from extinction found the Canadian birds' nesting grounds and, beginning in the late 1960s, started taking some of those eggs to resurrect the species by raising birds in captivity.
State officials have been talking about trying to establish a year-round whooper population in Florida for nearly 20 years.
In 1993, they persuaded the U.S. government to send to Florida some captive-raised whooping cranes from a wildlife refuge in Maryland. The hope was to start a colony on the Kissimmee Prairie, selected because it is home to hundreds of sandhill cranes. Others have been shipped down from the International Crane Foundation in Wisconsin.
The new parents are one of each: The male came from Maryland, the female from Wisconsin, each nearly five years old. Cranes mate for life, but with this pair, the female had never laid eggs before.
Mr. Folk and other biologists started keeping an eye on the pair about a month ago when they began "building on a nest platform like crazy," Mr. Folk said.
From then on, the pair stuck close to the nest, taking turns sitting on the eggs to incubate them.
Mr. Folk said biologists hope to get photos and video footage of the nest, but no one will get close to the chicks until they are 70 days old, if they live that long. Then biologists will want to band them.