Neither falling nor melting snow can disturb the thousands of brown bears sleeping blissfully in Estonia's forests through the winter until March. However, at Elistvere wildlife park, there is one bear, who has not hibernated for years and has no intention of starting now.
Karoliina the bear has lived at Elistvere wildlife park for 25 years. Every winter, she prepares a nest or bed in her enclosure, but then decides not to use it for hibernation.
Yet, according to the wildlife park's center manager Andri Plato, Karoliina is noticeably sleepier during the colder spells in winter and becomes more active when temperatures creep up a little higher.
"It's raining (at the moment), and so sleeping on this nest doesn't really work out. Who wants to sit somewhere for a long time if their bottom is cold? And besides, she knows she's going to eat," Plato explained.
According to Egle Tammeleht, a mammalogy researcher at the University of Tartu, in the wild, bears' hibernation patterns are not affected by the weather conditions to such an extent.
"When a bear makes a nest, it chooses a place and covers the ground. Bears should already be aware and understand, that occasionally the snow melts (in winter) in Estonia. Young bears might not be as good at making or choosing a (spot for a) nest, but in general they should be fine," Tammeleht explained.
For Karoliina, whose sleep patterns are disrupted somewhat by the wildlife park's visitors, hibernation is not essential. Her energy reserves are replenished by the park's staff, who keep her well-fed throughout the winter. In the forest, however, it is difficult for bears to find food during the winter months.
Despite this, bear tracks were spotted in southeastern Estonia as recently as last week.
"It happens from time to time," said Tammeleht, adding that when it does, it is usually due to human activity in the forest, such as logging or hunting having disrupted the bears' nests.
"(In these situations) they have to find a new place to stay, because in winter, they generally can't find food," Tammeleht explained, pointing out that this can have serious implications, not only for the bears themselves, but also their offspring.
"In the case of a female bear, she may have cubs in her nest, which can't cope without their mother and (as a result of her leaving – ed.) will freeze to death," Tammeleht said.
Bears in Estonia generally wake up from their winter hibernation in the second half of March. However, if there is very long thaw, as the snow starts to melt earlier than usual, some bears may emerge from their seasonal slumbers even sooner.
Editor: Michael Cole