A Californian condor has laid an egg in Mexico for the first time since the 1930s, with scientists watching like hawks in the hope that it will hatch any day.

The birth of a condor, one of the largest species of birds on Earth and featured on the coats of arms of several South American countries, would help to reintroduce the massive scavengers to the skies of Mexico several decades after being wiped out there.

The egg — which belongs to a seven-year-old female named Condor 217, born in the Los Angeles Zoo — was found in an abandoned eagle’s nest on a clifftop in the Sierra de San Pedro Mártir National Park, about 100 miles south of the US-Mexico border on the Baja California peninsula.

Condors do not reproduce until they are several years old.

“This is a momentous occasion,” said Mike Wallace, a field scientist at the Zoological Society of San Diego, who helped to find the egg. “We are all excited.”

A young condor cannot fly until it is six months old and it will roost and hunt with its parents for the first two years of its life.

Condors are the largest flying land birds in the western hemisphere, with wingspans up to 3m (10ft) They mate for life and one bird in captivity survived to the age of 77. Like humans, condors blush in response to emotions — their way of communicating with other birds.

Scavengers by nature, condors will fly up to 150 miles a day in search of carcasses. Because of the birds’ size and their ability to rip through hides, they can feed on much larger animals than other scavengers, often eating so much they can no longer lift themselves off the ground.

The population of Californian condors has been devastated by a shortage of seals and otters to feed on.

The use of poison to kill grizzly bears in the 1800s, along with hunting, egg collecting and power cables, also severely affected world populations. By the 1980s there were only 22 condors left but thanks to a captive-breeding programme the worldwide population now stands at 280.

More than 100 of these condors now fly free in the skies above parts of California, Nevada and Utah. Working with the Mexican Government, biologists reintroduced captive-bred condors to Mexico five years ago.

Another species of condor, found in the Andes, is also under threat, but its numbers remain in the thousands.

After discovering the condor egg, scientists climbed up to the nest and took photographs and measurements, shining a bright light through the shell to find out its age: 45 to 50 days old. Condor eggs typically incubate for 57 days, meaning the chick could hatch any day. There is a risk that the egg is dead but Mr Wallace said that he did not smell any sulphur and was reassured that its parents were still tending to it.

“We are all sitting on pins and needles waiting to see where the situation is going,” he said.

Big bird, giant appetite

— Only one egg laid at a time and incubated

— Average life expectancy is 60 years

— 10ft (3m) average wing span of fully grown bird

— 55mph (88 k/mh) top speed in flight

— 15,000ft (4,600m) altitude to which condors soar

— 2-3lbs (1-1.36kg) of meat can be consumed in one go by 25lb birds Source: San Diego Zoo

Source: San Diego Zoo

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