A caretaker at Domaine des Grottes de Han, a wildlife park specialized in European animals, Valerian Boudart said the large carnivores had lost weight during their three to four-month-long hibernation and would spend the summer trying to regain strength before the winter.
Boudart sought to clear up a common misconception by explaining that hibernation was not synonymous with continuous sleep.
"They do not sleep continuously for three or four months. They do so in small phases. They remain attentive to all external noises," he said.
Found across North America and Eurasia, brown bears thrive in certain areas such as Scandinavia, Russia, Canada and the northern United States.
They are classified as least concern, according to the International Union for Conservation of Nature and Natural Resources.