11/28/2014 6:36:07 PM
Why Are Bears Losing Their Hair?
Balding bears - what's causing polar bears to lose their hair in Alaska? A new study published in the Journal of Wildlife Diseases indicates that some polar bears in the Southern Beaufort Sea are suffering from unusual alopecia, or hair loss.
As part of ongoing research and monitoring efforts in Alaska, researchers temporarily captured nearly 1,500 polar bears between 1998 and 2012 from the Southern Beaufort Sea area. Along with standard data collection, they gathered information about the bears' health status. They found that, over the study period, more than 3% of bears were losing fur along areas of their head, shoulders, and neck.
The number of bears with the syndrome varied widely between years, with a maximum 28% of bears displaying active fur loss in 2012. Two outbreaks, including 2012, prompted intensive veterinary research by partners in an attempt to sort out possible causes. Everything from ice balls (physical hair loss), disease, bacteria, fungus, and nutrition were considered.
Polar bears need their thick fur, along with abundant body fat, to keep warm in harsh Arctic weather and while transitioning from sea to land. Without dense fur for insulation, polar bears condition, and ultimately survival, could be complicated during some seasons.
The recaptured bears who had active alopecia in the prior year were thinner than their furrier counterparts, which may indicate the loss of hair was a stressor or the hair loss and reduced body condition was the symptom of other stressors.
"While some hair loss in animals is common and associated with abrasion, what I saw in 1999 while working for USGS and what they observed since with another peak in 2012 was clearly different," said Geoff York, chief conservation scientist at PBI. "In both cases we were unable to isolate a causative agent, but ongoing research such as that presented here has eliminated some variables and is a step towards finding both the causes and understanding potential impacts of this condition for polar bears."