Bear cubs in US are developing an unexplained illness that makes them friendly and not afraid of people
- Black bear cubs in California have been showing "dog-like" behaviour and losing fear of people.
- Officials say the behavior is on the rise, and likely linked to a brain condition.
- Scientists don't know the exact causes, but have identified 5 viruses that could be to blame.
- For more stories visit Business Insider.
Some black bear cubs in California have been exhibiting uncharacteristic overly-friendly "dog-like" behaviors, and scientists aren't sure why.
The California Department of Fish and Wildlife (CDFW) picked up a small female black bear with this kind of behavior from the Pollock Pines, east of Sacramento, last month, the Sacramento Bee reported on Sunday.
The young bear, who was very underweight for her age, "moved into" a residential backyard, and was completely comfortable around people, picking up apples and eating them in front of the residents on their backyard patio, the CDFW reported.
She did not respond to people shooing her away, yelling, or clapping. At one point, the bear jumped into a housekeeper's open car trunk, the CDFW said.
This is "not normal behavior" and that it raises "red flags," CDFW wildlife veterinarian Dr. Brandon Munk told local news outlet KPIX-TV.
This is not the first report of these weird behavior patterns. The phenomenon was first flagged in 2014.
Like other bears picked up before her, the small female in Pollock Pines also displayed a characteristic head tilt and walked oddly.
A bear with this kind of behavior was captured by a snowboarder in 2019 as seen in the video below:
In one instance, a bear walked into a classroom and "sat at the back just like a puppy dog," Ann Bryant, the executive director of the BEAR League, a not-for-profit organisation in the Lake Tahoe Basin, told KPIX-TV.
Using CT scan and autopsies, scientists have found that this behavior was linked to encephalitis, a condition in which the brain is inflamed. But it is not clear what causes this disease.
Five new viruses have been identified in these sick bears, but scientists don't know if they are linked to the symptoms.
If these viruses are found to be the cause of this disease, there shouldn't be a risk of humans catching them, Dr. Jamie Sherman, a veterinarian at UC Davis One health institute, told the Sacramento Bee.
In the past 12 months, four bears with these symptoms have been brought in to authorities, the CDFW said.
The situation is becoming "more common in the Tahoe Basin and elsewhere in the state," the department said.
One bear was spotted in Humboldt County, which is a 366 mile drive from Lake Tahoe, and some have been seen on the Nevada side of Lake Tahoe.
Bears with this neurological disease cannot survive in the wild. Some, like the young black bear who hugged the snowboarder in the video who is now called Benji, have been placed in wildlife care facilities and zoos, the CDFW said.
The small female picked up in Pollock Pines, however, was euthanized.
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