"I was so excited. There was life!" he recalls.
On June 21, Zhao witnessed a 80-gram newborn.
But his joy was short-lived. The very next day, he had to address a crisis - a second crane was born at midnight but because the surrogate mother did not notice it, it caught a cold.
"When I cradled it in my palm the next morning, the little one couldn't raise its head," says Zhao. "It was gasping for air, eyes immobile, its feet collapsing to a kneeling position. But I didn't give up."
He mixed some amoxycillin meant for children's respiratory illnesses with some minced meat, yolk and corn bread. Slowly, the weak one recovered to Zhao's relief. The young survivor is now almost 0.7 meters tall.
Having spent so much time together, the cranes have grown to trust Zhao. They seem to share a language, only comprehensible to Zhao and the birds.
"The birds only react to Zhao when Zhao speaks to them, but I don't get the same reaction when I talk to the cranes," says Wang Xiaoyin, Zhao's apprentice.
There are a dozen other kinds of cranes on the island, separated by a gate and closed to the public to ensure the cranes' privacy. Zhao "speaks" different crane languages to communicate with them.
As an animal psychiatrist, he is able to peer into a crane's eye and parse its mood. With one look, he can tell if an animal had a spoiled childhood spent in an affluent zoo, or is from a nuclear family in the wild.
But Zhao opines that the art of crane-raising is impossible to impart. He says charts and books are unreliable. And it is insufficient to listen to the experiences of others. "If you put your whole heart into it, you will not fail. You have to try to trace their footsteps."
Zhao did not choose this vocation. He started working in the zoo after graduating from middle school, but at that time he didn't think he would make it a lifetime career.
With no special skills and a vague understanding of the "elegant creature" which supposedly has a long life span, he treated the birds like how he would a human friend.
Now, decades later, he can interpret the bird's slightest chirps.
He misses communicating with a demoiselle crane. "The demoiselle, like a Chinese princess, is delicate and dependent," Zhao says, adding that the demoiselle used to follow him around and would sometimes dance for him.
"It's just like having a friend. You don't know everything about them. You don't always know their whereabouts. But you want to know and understand them better. And the feelings are always mutual," adds Zhao.
Contact the writer at sunye@chinadaily.com.cn.