Bears Act Like Friendly Dogs Due To Strange Brain Disease

A mysterious disease makes some black bears friendly and fearless to humans, among other strange symptoms.

Researchers believe the disease, which appears to affect young bears around one year old, is some kind of encephalitis, which is inflammation of the brain, according to a press release from the California Department of Fish and Wildlife. at the end of last month. Since 2014, a handful of bears in Nevada and California have shown signs of the disease, and four bears in California were confirmed to have it last year.

“The first bear I personally saved was diagnosed with encephalitis in March 2018,” Ann Bryant of Bear Education Aversion Response told Live Science. “She walked into a school and walked into a classroom where she sat among the children, behaving like a friendly dog.”

Encephalitis has other serious effects on bears, including tremors, tilts of the head, and seizures. Affected bears also tend to be severely underweight. A female bear, seen in February picking up an apple and eating it among humans on a patio, weighed just 21 pounds when she should have weighed around 80 pounds. She was also covered in ticks, walked strangely, and was ultimately euthanized.

It is still not clear exactly what causes brain inflammation. But during the study of the phenomenon, scientists identified five previously unknown viruses in affected bears.

These viruses are believed to pose no risk to humans, said Jamie Sherman, a veterinarian at the University of California, Davis’ One Health Institute at the Sacramento Bee.

Bears with encephalitis usually need to be euthanized. Their symptoms make them unequipped to survive in the wild, and those placed in zoos or sanctuaries can become “a huge burden” because of the lifelong medical care they’ll need, wildlife vet Brandon Munk said in the CFDW press release.

However, two bears with neurological problems in recent years have been able to find new homes. One, now named Elinor, was brought to the Orange County Zoo. The other bear, who had gone viral after being filmed sniffing a snowboarder and now named Benji, lives at the Ramona Wildlife Center at the San Diego Humane Society. Last month, Benji celebrated his third birthday there with a fruit cake and mashed potatoes.