An unusually warm winter has caused bears to stir early from hibernation in several countries, raising concerns of an increased number of conflicts with humans.

There have been multiple sightings of bears emerging from hibernation in February and early March in Russia, Finland and the US, a situation apparently triggered by the mild winter experienced in many countries.

This winter was the warmest ever recorded in Europe “by far”, according to scientists, with the US just experiencing its hottest December and January on record.

Moscow Zoo has been preparing to deal with the emergence of two Himalayan bears a month early, while a grizzly bear sighting was reported on 3 March in Banff national park in Canada, the earliest such sighting in a decade.

Bears are also on the move in theYellowstone national park in the US, with a grizzly spotted prowling around the park’s famed Grand Prismatic Spring on 7 March. Park officials said that visitors should keep at least 100ft away from the bears, not to run away and keep bear spray to hand.

It’s not just bears that have been waking early from their hibernation slumber – there are also reports of an itinerant groundhog in Maine.

Although there is sparse data on hibernation trends, experts have warned that the climate crisis could be spurring a harmful mismatch in seasons for animals, especially those who hibernate through the cold winter months when food is scarce.

Among bears males are usually the first to emerge, in March or April, followed by females and then females with cubs. If they emerge in unusually warm winter weather, they may find there is little to eat.

“From my experience we are hearing more reports of bears out in late February and early March,” said Chris Servheen, the former grizzly bear recovery coordinator at the US Fish and Wildlife Service.

Servheen said he had heard about black bears coming from hibernation already in the Rocky Mountains as their snow dens melt and they are forced to leave their soggy homes. Even some grizzly bears at high elevations are departing their dens too.

“We aren’t sure why they are coming out earlier but if there are more sunny, warm days they sense that, they see the conditions are good and they go out,” he said. “The problem is they can’t stay in but there’s nothing for them to eat. They are burning up energy moving around but the plants haven’t started to grow yet, I’d expect it’s not a good thing for them.”

This mismatch raises the possibility that hungry bears will be involved in confrontations with humans as they desperately search for food. Towns in Canada and Russia have been the stage for tangles between people and bears as the ursine visitors ransack bins and gardens for food.

“If we see this as a continuing thing with climate change we will probably see more conflicts because there’s not much food for the bears,” Servheen said. “If bears come out early they will potentially seek food around people, such as in garbage, bird feeders and crops. The potential for conflict is certainly higher as they come out earlier.”