Why would a female crane reject its own kind and show its love to a male keeper?

Editor: Sunny Morning

**A female crane fell in love with a male keeper, ****and the two were together for 19 years,**This sounds ridiculous, but it really happened.

Chris Crowe, an American male animal keeper, has loved animals since he was a child. He has recorded wood ducks in Blackwater and Patuxent National Wildlife Refuges, introduced bald eagles in the California desert, and monitored wolves on the hillsides of North Carolina. In 2004, Crowe came to the Smithsonian Conservation Biology Institute and became a keeper here.

With his rich experience in animal breeding, Kro was full of confidence. However, he soon found out that he was too optimistic - among the animals he managed, there was a crane that caused other colleagues a lot of headaches.

This is a female crane named Hu Tao, a white-naped crane with roots in China. The white-naped crane is a bird of the family Gruiformes, and is called the white-naped crane because it is white from the back of its head to the back of its neck. The exposed skin on the face of the white-naped crane is red, so in ancient times it was also called a red-faced crane or a red-cheeked crane, so it is also known as a red-faced crane, a white-crowned crane, or a native crane .

If you see a large crane with a white nape, a red face, and a lead-gray body in the wild, it is a white-naped crane. The white-naped crane is a first-class key wild protected animal in China. The population is very rare, with less than 7,000 in the world . It is listed as an endangered species in the Red List of the International Union for Conservation of Nature (IUCN) .

As a rare species, its first mission is to reproduce. Who would have thought that Hutao, a white-naped crane, would not be willing to get close to its own kind, nor would he like a partner of the same kind ? Why is this so? This has to do with its growth experience.

Both of Hu Walnut's parents were poached from the wild. After being rescued, they were sent to the International Crane Foundation. Because their specific origins and health conditions were not certain, they remained at a research center in Wisconsin.

Walnut's parents have the same mission. In order to stimulate the mother bird to lay more eggs, people will steal eggs for each one she lays, so that the mother bird will continue to mate and lay eggs. The stolen eggs are incubated by machines and cared for manually. They laid 9 chicks here, and Walnut is one of them.

Although this can improve the reproduction rate and survival rate of birds, it also brings a very serious problem: when these birds hatch, the first person they see is a human, and they will think that humans are their parents, which will then lead to a series of identity recognition problems, such as unwillingness to get close to their own kind and not liking partners of the same kind. In science, this is called the " imprinting effect ."

What is the imprinting effect? ​​The first person to discover the imprinting phenomenon was German behaviorist Heinlotte . In 1910, German behaviorist Heinlotte discovered a very interesting phenomenon in an experiment: a gosling that had just hatched would instinctively follow its mother when it first saw her. However, if the first thing it saw was not its mother, but other moving objects, such as a dog, a cat, or a toy goose, it would automatically follow it. What is particularly important is that once the gosling has formed a following response to an object, it will no longer be able to form a following response to other objects. The formation of this following response is irreversible, that is, the gosling recognizes the first but ignores the second. This phenomenon exists not only in lower animals, but also in humans .

Later, Heinlot's student Lorenz proposed the concept of imprinting in his research on Anatidae, especially ducklings, based on previous research results. Imprinting is a special way of learning. It is different from general conditioned reflexes or habit formation. It only occurs in a specific stage of animal intelligence development, which is called the sensitive period or critical period. This is the case with walnuts, which have a very strong human imprint .

Most female white-naped cranes can reproduce at the age of 3, but Hutao thinks she is a human being, so she has no intention of looking for a mate of the same kind at the age of 23. In order for Hutao to give birth to offspring smoothly, the breeders found many excellent male cranes for her, but she killed two suitors, which means she has a bad reputation.

In 2004, Walnut was sent to the Smithsonian Conservation Biology Institute. At that time, Walnut was 23 years old. She finally fell in love, but not with cranes, but with the keeper Kro.

Initially, Crow and Walnut didn't have a good relationship, but Walnut was not afraid of people, and when he first saw Crow he didn't hide, but instead behaved in a threatening manner: he fearlessly walked up to the wire fence, raised his feathers and growled.

Crowe is a very responsible person, and he still takes care of Walnut in every detail in life. Slowly, Walnut let down his guard, and as they spent more time together, Walnut unexpectedly fluttered his wings and ran around towards Crowe, shaking his head and flapping his wings. Later, he realized that this was Walnut expressing her love to him.

In bird courtship, it is usually the male who shows himself off to the female (mostly by dancing) in order to win her favor. But as a "single girl", Walnut obviously couldn't wait any longer, so she took the initiative to send courtship signals to Crow.

In order to preserve the white-naped crane genes that Hu Walnut cherishes, after consulting a lot of information, Kro tried to get closer to Hu Walnut, such as proper caressing, nesting, incubating eggs, etc., and then looking for the right time to inject Hu Walnut with the male crane's seeds through artificial insemination. From 2005 to 2020, Hu Walnut gave birth to a total of 8 offspring.

In early January 2024, Hu Tao was admitted to an animal hospital because he refused to eat or drink. Even after treatment, the 42-year-old eventually died of kidney failure!

At this point, the story seems to have ended, but we can't help but wonder: Is the relationship between Walnut and Claw considered love ?

From Walnut's perspective, the answer is yes . White-naped cranes are strictly monogamous birds, and after pairing up, the adult birds will maintain a lifelong bond . This bond is not only related to reproductive behavior - according to Crowe, in the first few years, whenever he returned to work after vacation, Walnut would always express dissatisfaction with the inexplicable disappearance of his "partner"; when he accidentally saw Crowe taking care of other female cranes, Walnut's anger was even more obvious. Obviously, Walnut has invested all his emotions in this relationship.

What about Crow? After nearly 20 years of companionship, Crow's emotional devotion to Walnut needs no further explanation. He even plans to live nearby after retirement to continue his lifelong "bond" with Walnut .

This is obviously not the kind of love that everyone talks about on Valentine's Day, which is limited to two individuals. It doesn't even belong to Walnut alone. But it is certainly love - this is a love letter that Crow dedicated to the beauty of nature. This love shines in the efforts of crane conservation around the world, and is also practiced by more animal conservation and environmental workers; even in the hearts of you and me who pay attention to these stories, the same love is surging for a long time.

Reference sources: Science Popularization China·Science Encyclopedia, Fast Technology, The Paper, Guokr Nature, Gezhi Lundao Forum, etc.