The linked studies in that section don't directly support what the article states.

The study in captive black bears controlled for things like access to food and water. Researchers completely removed access to food and water to trigger hibernation and the end of hibernation in the bears to monitor them.

The study on wild brown bears found that they were very susceptible to disturbance and would move dens during the winter if disturbed, so not in a total hibernation. It also directly calls out the black bear study as having hibernation artificially started and ended and not representative of the wild.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4750243/

>In a previous study, the HR in captive black bears was reported to decline gradually over five weeks from the date that food and water were removed [45]. Our finding that changes in Tb began long before changes in HR suggests that studies on captive bears with an artificially defined end of the food/water season might not represent the actual sequence of events in the wild.

They concluded that hibernation is driven by environmental factors rather than the physiological factors that the black bear study concluded, and that periods of warming can drive them out of their dens or delay hibernation.

They also highlighted the need for differentiating between small mammal hibernation and bear hibernation because of these.