[ad_1]
Animals are underweight, shaking, tilting the head, and are unusually friendly
A mysterious symptom complex that has appeared sporadically in young black bears in the Tahoe Basin in recent years has now appeared in two severely deficient yearlings found in northern California in the past five weeks.
The sick youngsters, both euthanized and suffering from brain inflammation, or encephalitis, were found about 15 miles apart in eastern Humboldt County and just across the river. Trinity County border in late February and early March.
A third bear, possibly a sibling, was seen in the same area on Wednesday showing similar symptoms, although it has yet to be captured, said Monte Merrick, director of the Humboldt Wildlife Care Center near Arcata, who received the first two.
Animals were the first known cases outside of the Tahoe area to show common symptoms, primarily encephalitis, documented since 2014, when the Nevada Department of Wildlife first raised the red flag on young bears. with neurological abnormalities in the area, officials said.
Fewer than 20 cases on both sides of the state border have since been examined, most in the Tahoe Basin, which has a large black bear population and ample opportunities for human encounters, experts said.
But the pace of discoveries has increased over the past 1½ years, in part perhaps because “we’ve really been looking,” said Brandon Munk, senior wildlife veterinarian at the Department of the Department’s Wildlife Laboratory. California to Rancho Cordova, where he started in 2016.
“Once you start looking, you start to find,” Munk said. “Anyway, we really don’t have a basis for how widespread this has been.”
Most grieving bears are about a half or a third the size they should be at a year old – but not as undersized as those that have passed through Humboldt County. Many have a strange gait or tilt of the head, tremors or other neurological symptoms, as well as dull, callous behavior or fearless “doggy” behavior towards people.
Researchers increasingly focused on the matter have discovered five previously unknown and unidentified viruses in tissue samples from some of these bears, as well as others available for various reasons. Two of the five viruses were ubiquitous.
The type of inflammation is reminiscent of a virus, Munk said, although scientists are far from linking the symptoms to any particular source and have not ruled out other causes. It is also not known whether bears suppressed their immune systems for other reasons and then succumbed to viruses or diseases that otherwise would not have proven to be fatal, or if their cases are only now appearing due to increased human interaction with wildlife.
“It could be related to urbanization, but at the same time there could be bears in the wild that have had this and we just haven’t seen them,” said Sanchez, of the Nevada Department of Wildlife. .
Denise Upton, director of animal care at Lake Tahoe Wildlife Care in South Lake Tahoe, said animals with the syndrome remain rare, but sometimes it’s hard to tell because humans are so careless about leaving them out. waste and other attractants or even directly feed the bears that they become accustomed to people.
In the meantime, his organization has increasingly treated and released severely insufficient cubs who were still young enough to be with their mothers, but who were not, for some reason. These animals, including four at the start of last year, had clearly gone out all winter on their own but did not have neurological deficits or other significant problems, Upton said.
“We don’t know what’s going on in the forest,” Upton said. But a hungry lion cub who sees a person “will not show fear because hunger outweighs his fear.”
“My question is, ‘What happens to all of their mothers?'” She said.
The two bears captured by the Humboldt County Wildlife Center were found wandering near the neighborhoods of Willow Creek and Salyer, about 260 miles north of Santa Rosa, Merrick said.
They were both about a quarter and an eighth of the expected weight for their age – around a year – with acute skin conditions, Munk said.
The female, captured Feb. 27 at just 10 pounds – the size of a lion cub even before being weaned, Merrick said – was initially considered for rehabilitation at Sonoma County Wildlife Rescue, one of three rehabilitation centers state approved wildlife. Then Munk looked at a photo of her.
“I said, ‘Eeeeeee. I know what it is, and the prognosis is poor, ”he recalls.
[ad_2]
Source link