Postcard from... Cantabria

February is supposed to be the month when bears all over the world prefer to hibernate.

But scientists in the sierras of Cantabria, Spain, have been baffled in recent weeks at the sight of up to eight different families of local brown bears roaming the snow-capped mountains of northern Spain when they should be getting the ursine equivalent of 40 winks.

The phenomenon of insomniac Spanish bears is not unusual in itself. Reports on the occurrence on the internet date back to 2008, and back in the 14th century, King Alfonso XI of Castile, the author of a book on hunting bears, wrote that it was because of restless cubs keeping their mothers awake on winter nights.

But it is the increase in frequency that is so puzzling.

“We have detected the phenomenon in other years, but in far lower numbers,” says Guillermo Palomero, president of Spain’s Brown Bear Foundation.

One theory is that after feeding their young through to the late autumn, mother bears need to stay awake so that they can recover their strength.

But that does not explain why two or three solitary bachelor bears have also been spotted in the snowfields. Not even the catch-all explanation of climate change really works, given that the 2012-13 winter across Spain has been much harder than usual, with two snowfalls in Cantabria in February.

Fortunately, missing out on a month’s sleep poses no risk to the health of the mother bears and cubs. The cubs seen are mostly more than a year old and strong enough to survive in wintry conditions.