Today, this great creature is on the brink of extinction.

According to the World Center for Birds of Prey based in Boise, Idaho, the Philippine eagle is the rarest of all large forest eagles.

Fully protected by law, the bird with a wing span of 2.2 meters (seven feet) was once a common sight throughout this Southeast Asian archipelago. Now it can only be found on the islands of Luzon, Samar, Leyte and the southern island of Mindanao.

No one knows with any degree of certainty just how many of these eagles there are in the wild today.

Some estimates suggest that up to 500 pairs might exist in the country, mainly in the Mindanao rainforests.

Just a short drive from Davao, Mindanao's largest city, is the Philippine Eagle Center where a small team of researchers has spent the past three decades working on a captive breeding program to save the eagle.

In April a 17-month-old eagle named Kabayan became the first born in captivity to be released into the wild.

According to the head of the center's breeding program, Domingo Tadena, it is "so far so good" for Kabayan.

The young eagle is fitted with a small transmitter weighing about 70 grams (2.45 ounces) and biologists monitor its every move.

Kabayan has managed to hunt and fly within a few kilometers (miles) from where he was released on April 22 at Mount Apo, 140 kilometres (87 miles) south of Davao.

It was Lindbergh back in the 1960s who convinced the former dictator Ferdinand Marcos that something should be done to protect the eagle and to save it from extinction. In 1970 Marcos declared the eagle a protected species.

According to Tadena, 57, it is now up to Kabayan to see how well he adapts to his new environment. The Mount Apo reserve covers some 75,000 hectares (185,2500 acres) but less than 40,000 hectares is natural rain forest.

"My only fear is man," said Tadena, who has worked with eagles for most of his adult life.

Tadena has been attacked and seriously injured by an eagle at the center but he has the utmost respect for what he calls "these magnificent creatures".

Today there are 29 Philippine eagles at the center, including 13 others born in captivity aside from Kabayan.

The center covers some 8.5 hectares (5.3 acres) of lush green rainforest and is home to a wide variety of native birds and wildlife.

For Tadena and his small team it has been a labor of love in a breeding program that has taken years to get right.

Begun in 1978, the captive-breeding program had many false starts.

It was not until 1992 that the world's first captive-bred eagle was hatched. Named Pag-Asa (Filipino for hope), the male eagle is the pride of the center.

"There were many who had their doubts," Tadena said. "But we persevered."

The center operates almost entirely on private donations and from what it makes from for the 100,000 tourists, mainly local Filipinos, who visit each year.

Tadena said the breeding program was being closely monitored internationally especially the artificial insemination program.

"The eagle is a solitary creature and very territorial," he said.

"Though we already know they mate for life and eagle pairs share parenting responsibilities, very little is known about how they meet and their behavior on the off-breeding season.

"This is one of the aspects to the research we have been conducting in the field."

Tadena said the center has had great success with birds mating in captivity but in some cases science has had to step in with artificial insemination, not easy with an adult bird.

Eight of the eagles at the center were conceived naturally and six through artificial insemination.

So how does one collect semen from a five-kilogram (3.1-pound) eagle?

"Well, it's not easy," says Tadena.

"The handler wears a specially made, very thick leather jacket with a hood. As the eagle lands on the handler's head he has to quickly use his hands to collect semen which is then transferred to a syringe for storage. It's not an easy job and requires a great deal of skill."

The handler of an eagle born in captivity has a vital role in the bird's life.

"When a bird is hatched in captivity a handler is assigned and that handler will stay with the bird for life.

"The bird first sees its handler as a parent then a mate. The handler will even help in nest building. The relationship is very strong and it is another aspect of the eagle's behavior we want to know more about," Tadena said.

In captivity the eagle can live for 40 years but out in the wild its life expectancy is around 20 years, according to Tadena.

"The reason for this is primarily due to loss of habitat mainly through logging and farming," he said.

He believes birds born in captivity can make it out in the wild but it is a question of timing.

"Kabayan, I think, was probably a little too old. But he is adapting to his new environment," he said.

Pag-Asa, however, will never be released.

From a perch high in his enclosure, Pag-Asa casts a careful eye over the small group of curious onlookers who have gathered below.

"Unfortunately we doubt if he could survive in the wild because all he knows is this," Tadena says pointing to the vast enclosure.

"It would be wonderful to see him out but the risk is too great. He might not know his natural food items such as lizards and small monkeys anymore.

"Here at the center the eagle does not have to hunt for his food. But despite his confinement Pag-Asa, like Kabayan, offers hope for the future survival of the species."

TERRA.WIRE