Visitors to Berlin's Tierpark on Saturday had their first chance to see the latest addition to the zoo's polar bear enclosure.



The cub, which has not yet been named, appeared to the public for the first time, a day after first emerging with her mother, 9-year-old Tonja, from the den.

Still getting used to the outdoor world, the baby bear lolloped around the enclosure, suckled and went for a swim. Visitors cooed over her every move, taking snaps of the new arrival.

'Bond between them is very close'

The cub, born on December 1, spent the first months of its life in darkness with her mother. Baby polar bears are born deaf and blind, and need intensive rearing.

"The bond between them is very close," said the zoo's polar bearkeeper, Florian Sicks. "Tonja is a very good mother, taking incredibly good care of her cub, never letting her out of her sight. We can't complain."

The mortality rate of polar bears is very high in the first three months of life.

"We are still extremely pleased with how the cub is developing," said Sicks.

Read more: Russian islands under polar bear 'invasion'

Successor to Knut?

Tonya lost three of her cubs in the past two years. Male polar bears have little input into the lives of their offspring and the cub's father, Wolodja, lives in a zoo in the Netherlands.

Zoo directors say the cub's name will be determined in collaboration with potential future adopters.

The zoo will hope the cub can go on to match the popularity of polar bear Knut, born in 2006.

Rejected by his mother, Knut had to be hand-reared by zookeepers. The bear garnered worldwide attention, and brought in millions of euros from visits and merchandise.

Knut also attracted widespread media attention, once featuring on the cover of Vanity Fair magazine and even appearing on German stamps.

Read more: The peculiar traits that made polar bear life possible

However, Knut died from a suspected brain tumor in 2011. A statue of him stands in the zoo.

A potential successor to Knut, Fritz, died of hepatitis at the zoo in 2017.

Because its Arctic habitat is threatened by climate change, the polar bear is listed as a vulnerable species by the International Union for Conservation of Nature (IUCN).

The population of polar bears in the wild stands at 26,000, according to the IUCN, and a European Union breeding plan is aimed at boosting bear numbers.

Mysterious death of polar bear Knut solved A heartbreaking story Knut was born in 2006 in the Berlin Zoo. The cuddly pup quickly captured the hearts of thousands, drawing crowds to the zoo and becoming world famous. In 2011, when Knut was four years old, the fan community was shocked when the polar bear suffered an epileptic attack, fell into a water ditch and drowned.

Mysterious death of polar bear Knut solved Two more celebrity deaths What made Knut's death even more tragic was that his zookeeper Thomas Dörflein, who had nursed Knut from a puppy into polar bear adolescence, also suddenly died of a heart attack in 2008. At that time Dörflein's fluffy foster child was two years old, and not quite so cuddly anymore. Together with Knut, Dörflein had also become a celebrity.

Mysterious death of polar bear Knut solved Uncertain diagnosis Initially, there was much speculation as to what might have triggered the attack: Was it Knut's mourning over the death of his foster-parent? Was he stressed out after being mobbed by other adolescent polar bears? The Leibniz Institute for the Research of Zoo and Wild Animals (IZW) investigated the circumstances and determined Knut probably contracted an infection that developed into encephalitis.

Mysterious death of polar bear Knut solved Research continued However, researchers were not fully satisfied with their conclusion, and the real cause of the disease remained in the dark - until now. Finally, the speculations have come to an end: In an article in the journal "Scientific Reports," published on August 27th 2015, researchers revealed Knut had an autoimmune disease.

Mysterious death of polar bear Knut solved A case for biologists and neuroscientists The paper reveals a new discovery: A disease called "anti-NMDA-receptor encephalitis," which until now was thought to only affect humans. This is the first proof that also animals can suffer from a version of the same disease. The research as made possible through cooperation between the IZW and the German Center for Neurodegenerative Diseases (DZNE).

Mysterious death of polar bear Knut solved Overactive Defense System "The defense system of the body goes out of control. It starts producing antibodies which turn against the body's own nerve cells rather than fighting infections," DZNE scientist Harald Prüß explains. The possible symptoms of anti-NMDA-receptor encephalitis include epileptic attacks, hallucinations and dementia.

Mysterious death of polar bear Knut solved Only recently discovered The mechanism was discovered in humans just a few years ago. That's why IZW researcher Alex Greenwood considers these new findings "pretty remarkable." The treatment for humans could now be adapted for zoo animals.

Mysterious death of polar bear Knut solved Knut's contribution to research "Autoimmune diseases of the nervous system could be more common among humans and animals than we have previously thought," Greenwood suggests. It is possible that inflammations triggered by an autoimmune response are often overlooked when doctors are treating people with psychoses or lack of memory. In the future, routine tests could be done to get the diagnosis right. Author: Hannah Fuchs/fs



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