Zhao Xisen has created a strong bond with the hooded cranes at Beijing Zoo, and the perennially tense birds allow Zhao to stroke them. Zhang Wei / China Daily

Zhao Xisen has managed to help a pair of hooded cranes at Beijing Zoo conceive after seven years of infertility. Sun Ye finds out more.

After seven years of infertility, the hooded cranes (Grus monacha) at Beijing Zoo are finally able to carry on their family line, with assistance from Zhao Xisen, who is an animal polyglot, vet, animal shrink and crane keeper.

With 30 years of self-taught crane-breeding experience, the mellow-voiced man says the secret of his success is to befriend the cranes. He gets to know them, respect them, and help them.

Over the past years, the 58-year-old Zhao has been documenting, feeding and matchmaking more than 500 cranes of rare species at Beijing Zoo.

"These hooded cranes are extremely watchful and cautious," Zhao says.

He has created such a strong rapport with the birds that the perennially tense white-heads allow Zhao to pat them. Normally, the cranes are so guarded against strangers that they launch themselves at the cage's railings whenever a stranger gets too close.

They are by nature a timid species - a whiff of strong wind or a squeak too loud will frighten them. These birds will not ovulate if there is the slightest change in their surroundings, which is why they have not been producing any offspring.

Although Zhao, winner of last year's Beijing Occupational Skills Competition for his crane-raising abilities, has reared more than 500 endangered cranes during the span of his career, making cranes conceive has proven to be a challenge.

Zhao decided to move the uptight crane couple to a reclusive corner on the zoo's island of cranes to provide them a serene sanctuary. "My team and I tried to learn their habits and create a comfortable environment," he shares.

To his team's delight, the cranes looked comfortable and calm - a positive sign to conceive.

But last year, the hopeful team's spirits were crushed when they saw squashed eggs within the compound. The overly alert and protective parents had sniffed danger and killed their unborn babies before the hypothetical enemies did.

Zhao and his colleagues quickly devised a new plan. They got a surrogate mother, months before the breeding season. The Siberian crane, more sedentary and careless, was to hatch for the edgy couple.

The arrangements brought Zhao a moment of glee. After 20 days of hatching, he placed one egg on the table for routine inspection. The egg staggered on its own accord.