The two brown bears of Helsinki's Korkeasaari Zoo, Sofia and her daughter Yulia, had exceptionally short hibernation periods this winter, totalling only about six weeks.
The bears went into hibernation in October, waking up early in December, and then went back to sleep in February for a week-long nap.
"We can't explain their peculiar winter sleep rhythm. The bears were very tired all winter and for a while we also gave them some carbohydrate-rich berries, which they eat in autumn when they refuel for hibernation. We also gave them more nesting material, all of which they took to their winter den," said Susan Nuurtila, a zookeeper at Korkeasaari.
The bears woke up again this month, and were greeted by new fixtures and treats to enjoy in their enclosure. Korkeasaari has posted videos of the bears on its website.
Last winter, the bears at Korkeasaari slept exceptionally well, accumulating over three months of slumber.
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